THE BRITISH OVERSEAS RAILWAYS HISTORICAL TRUST
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Journal Institution of Locomotive
Engineers
Volume 36 (1946)
The IMechE virtual library is accessible (full papers, all diagrams, photographs, extensive tables, via SAGE |
Journal No. 189
Topham, W.L. (Paper No. 456)
The running man's ideal locomotive. 3-29. Discussion.: 29-91.
Mainly concerned with rugged locomotives for rugged terrains, based
mainly on experience gained during WW2 in Persia (now Iran) and Egypt: oil
firing tends to colour his views. Noted the "unquestionable" desirability
of three-cylinder type for high speed passenger work (either 4-6-0 or 4-6-2),
and for heavy freight jobs performed by 4-8-0 or 2-10-0 types. The two-cylinder
4-6-2, such as the Indian Standard XB class or the BAGS 12K "is to be eschewed
as it hunts notoriously in service especially if provided with Cartazzi slides
for the radial wheels instead of helical return springs. Nevertheless did
acknowledge the success of LMS class 5.
His proposed "ideal" would have had 5ft 9in coupled wheels, 21in
cylinders, a parallel boiler with Belpaire firebox operating at 220 psi.
The parallel type was cheaper to produce and cheaper than the taper type.
A steel firebox should have been fitted as the copper type was out-moded.
Longitudinal stays rather than roof bars were specified. With oil firing
roof stay nuts burned. Welded fireholes as used on Buenos Aires Great Southern
and BAW were found to be effective. The method employed in the USA for fixing
superheaters should be adopted. Three fusible plugs of the type employed
on the Egyptian State Railways should be used. "The boiler needed to be big
enough for the engine, many good engines were spoilt by too small boilers".
Multiple valve regulators combined with the superheater header both avoids
the use of snifting valves and ensures that steam is retained in the elements.
It was noted that the GWR locomotives had no domes yet the regulators were
located in the boiler steam space. Some of this followed experience with
8F 2-8-0s fitted with oil firing: notably burning of torpedo ends of superheater
elements. More washout plugs were required to ensure adequate accessibility.
Topham considered that the header joint which leaked least was the old Midland
Railway pattern of plain face-to-face type. There was further criticism of
the 8F: the superheater tubes were only 11 SWG and there had been many burst
elements in Persia and Egypt with oil-firing: 9 SWG was advocated. Shorter
superheater elements were advocated for oil-firing. Considered that superheaters
should be fitted with shut-off valve in the event of burst elements.
The standard GWR smokebox combinging drum with saddle was advocated. The
Midland Railway smokebox door was an excellent one and should be fitted with
six circumferential clamps. All pipework in smokebox should be of steel not
copper as latter deteriorates. Many failures were experienced with GCR ROD
type due to lack of belling and welding in steam pipe connections. The blower
ring cast integrally with blast pipe cap as fitted to Midland Railway and
Egyptian State Railways was recommended. The steam fountain should be placed
outside the cab on top of the firebox. This improved accessibility and avoided
heat in the cab. Injectors need to be capable of working at high ambient
temperatures (as in Persia where feedwater temperatures reached 96°
to 109° F): the Seller's monitor injector was simple to
change (Figure) and the Nathan injector was also
advocated. Feed water pumps and heaters were deprecated ("never live
up to reputation in practice").
Advocated clackboxes on side of barrel with a stop valve, Considered
that top feed led to priming. Water gauge of Klinger reflex pattern. Whistle
should be of Caledonian type and on cab roof.
Noted the gymnastics needed to operate LNWR brake valves. Advocated crosswise
rather than fore and aft operation of brake valve. Westinghouse vacuum ejector
was simplest. The blower valve location was critical. Liked the double sliding
firehole door fitted by the LMS and GWR. Noted the need for cab seats and
advocated thick glass windscreens as fitted to LNER Pacifics
and Italian locomotives. Steel chequered cab floors with duck boards under
the crew's feet were recommended.
Plate frames were advanced, but these needed to strengthened around the horms:
"when a Baldwin 2-8-2 and an LMS 8F collided in Persia it was
easy to see who got the best of it" (p. 16). It was considered that bar
frames were very weak at the front end. Disc wheels for the
bogie were abhorred: "you cannot see what is going on". Commended King class
bogie's external axle boxes (17). Automatic pressure relief valves for
the cylinders were demanded. Poppet valve gears were too prone to catastrophic
failure for the service envisaged. The Walschaerts valve gear as developedd
for the LNER V2 class was admired. One suggested modification suggested for
the union link from the crosshead to the combination lever was for it to
be coupled directly to the small end pin as in the USA and on Italian
locomotives. Pennsylvania type piston valves were advocated. The screw-type
reversing gear as used on the GWR, MR compounds and 2P class was admired.
The pistons, crossheads and rods should be of cast steel. A solid single
slidebar with renewable bronze slipper liners was recommended and all nuts
should be catellated.
The 8F solid bronze bushes with white metal inserts gave excellent
service.Knucklepins gave a lot of trouble in service, and should be catellated.
Springs should be laminated throughout. Compensating gear good theoretically,
but in practice has a lot of disadvantages. Compensating beams add to the
weight. Hangers need to sufficiently large. Advocated LMS latest type of
axleboxes. In lubrication "grease is the thing", advocated grease guns and
candles wherever possible. For the valves and pistons the Detroit sight feed
lubricator was better than the Eureka type as the latter gets hotter in service.
Flexible rubber connections for lubricants were deprecated as they burnt
away. The sandbox should be placed on top of the boiler. A wooden cowcatcher
was prefered to steel ones. The Whitaker Automatic Staff Exchange Apparatus
was commended (see son's comments in Discussion). The GCR ROD ashpan received
specific condemnation as the trailing coupled axle was completely surrounded.
The tender should run on four-axle bogie type with the number on the sides.
It should be all-welded.
Discussion
The President, F.S. Whalley (29-30) noted that "if a thing was complicated
in proportion to its function it was wrong". Draughtmen should have running
experience. Operating staff should be involved in design.
A.H. Whitaker (30-2) disagreed with statement on parallel boilers: he
preferred the taper type. He considered that superheating was taken too far
on some freight engines: it was suitable for long-haul, but not for lighter
work. The boiler needed to be lagged. During WW2 "'his Company' (LMS?) had
borrowed some old engines (K10?) from the Southern Railway, and they had
wonderfully efficient injectors which could be detached in a very short time":
these were presumably Urie-type. Agreed for the need of strong buffer beams.
Thanked the speaker for recognizing
his father's work.
W. Cyril Williams (32-3) was critical of Topham's slant: 8F class
were neither designed for Persia nor for oil-firing. Also suggestion that
excessive emphasis placed upon Argentina and worse still Italy. Highly critical
of Topham's observations on bar frames: the British locomotive industry had
exported hundreds of locomotives with bar frames. Power reverse was essential
for large locomotives
P.C. Dewhurst (43-5) said that he agreed with many
of the practical points brought forward by the author as examples of where
the Running Department should have intervention m design: that the very existence
of his claims regarding such cases seemed to indicate a lamentable lack of
co-ordination between "design and repairs" and "operating" sections on some
railways; that the incidence of such cases was in proportion to the lack
of such co-ordination; and, finally, that on railways where the old system
of the C.M.E. (or Locomotive Superintendent) having control of both "traction"
and "works" -in which respect he had perhaps been fortunatestill
continues, the two aspects of the problem receive, automatically, combined
consideration. Where he disagreed with the Author-confining to principal
items and in the order of their appearance in the papewas upon the
following:
The true "Cartazzi" axlebox did not "hunt"; its inclined-plane control making
it altogether the steadiest of all lateral-control boxes if the planes were
adequately inclined. Had the Author had in mind the plain sliding-lid axle
box which he understood the Indian 4-6-2s had originally. There was no need
to employ a Belpaire firebox; a round- topped pattern with direct roof-stays
would save at least half a ton, which weight could be used in a greater diameter
of boiler barrel. It was not necessary to shorten superheater units to the
extent of 4 ft. from the firebox on oil-burning engines; 20 inches in the
case of coal-burners and 30 inches with oil-fuel had been proved satisfactory
on railways having very long full-throttle hauls. The suggestion that clack-boxes
should be at the side seemed insufficiently substantiated; plain top feed
reduced fire-tube corrosion and avoided deposit collecting around and in
the water-entrance. The incorporation of a stop-valve was, of course, an
ancient practice, and whilst it was effective with top- feed, he had never
known it workable with a side-feed clack-box-the stop-valve was always "limed
up."
The Author said main frames should be "unquestionably of plate type and not
bar," adducing that they made a very weak front end; then going on to say
that with plate frames, "immediately in front of and behind the cylinders
... was where cracks invariably occur ... if double thickness were employed
at these weak points that would probably not occur" (!) The question of plate
versus bar frames could not be cursorily dismissed like that. As a fact,
the bar frame did above all things afford a more convenient cylinder fixing
and a much stronger connectionespecially laterallyfore and aft
of the cylinders than did the plate frame; was the Author referring to the
old style single bar pattern and not the present-day two-bar frame connections?
The many other points where the bar frame was superior to the plate were
too numerous to mention m comments such as these, but running men with expenence
of modern bar frames generally have no doubts that the bar pattern provides
the best shed-repair job.
The questIon of the most preferable valve-spindle guide was interlocked with
the other valve-gear parts. The cross head type guide allowed the use of
a plam straight symmetrical combination lever the whole weight of which together
with the connected members was centrally hung from the valve-spindle crosshead;
the circular bush-type guide carried a lot of, gear by overhang and moreover
could not assist in keeping the gear square." It seemed remarkable that the
Author as a running man, . although. making various suggestions regarding
couplmg-rod crank-pin nuts, did not.mclude that of making the trailing pins
and nuts IdentIcal.wIth the leadmg ones; in that manner obtaining the advantage
of easy interchange of leading and trailing wheels when tyre-flanges were
thinning, etc.
The Author disagreed with compensating spring-gear, mentioning two suggested
disadvantages; that question, like that of bar versus plate frames, could
not be dealt with thus summarily. There were many advantages both !o the
locomotive and the track which in his experience altogether outweighed those
mentioned, but space forbids extended dIiscussion here. The same thing applied
to wedge-horns; how would the Author get 150,000 miles between general repairs
without wedge-horns? Incidentally: he referred to broken wedge-bolts; perhaps
a more extended expenence with bar frammg would alter his opinion of
wedgesas also regarding bar frames.
In his references to "under" Iubrication of axle boxes being preferably by
"good soft white cotton waste" and not" hard wiry coloured stuff,': the Author.
appeared to have overlooked the fact that an elastic matenal was required.
The proper "wiry coloured stuff" was a fairly apt description of the
generally most effective packing whilst the "soft white cotton" might ir:dicate
precisely the kind so apt to "sag" away from under the axle journalthe
principal cause of hot boxes with under. lubrication .. As to mechanical
lubrication of coupled axle-boxes, it could certamly be said that railways
using that system were those whose lubricating costs and hot-box records
were amongst the lowest known. Mechanical lubrication, combmed with taking
the responsibility for shed preparation of engines away from the drivers,
was the greatest antidote to "pooling engines" disadvantages so far discovered,
A completely effective method of preventing "splay" of brake-blocks was to
design the top hanger-pins of adequate length and the cross-beams wIth adequate
secunng nuts and cotters outside the brake-hangers; this also reduced wear
to a surprising extent. Very surprisingly the Author advocated wooden
cowcatchers; to most running men and otherssuch are anathema. The best
cowcatchers were those made of (old) tubesset "vertically," thus preventing
sagwith their ends flattened for bolt-holes, etc. Strange: also, was
his advocacy of wire- netting over the chimney top; practice many years ago
showed such nettmg lasts a very short time.
Regarding tenders. Openings all along the tender sides would lead to
accumulations of fuel and debris around the injector water-valve outlets,
whilst the suggestion that tenders should carry 6,000 gallons of water and
12 tons of coal seemed to indicateas indeed appeared in other parts
of the Paperthat the Author in his ideal locomotive had in mind an
engine for a particular set of conditions. Summarizing the whole matter as
propounded by the Author "by and large," it certainly appeared that between
the two extremes, the Running Department which would seem to have one guiding
principle to keep engines moving with the least possible trouble to
themselves, and the Builderswhose object naturally was to supply what
they believed to be the-best engine for more or less understood conditions
at the least possible production cost (both important principles and objects,
but by no means the whole picture), the principal function of a locomotive,
viz., to produce the greatest ton-miles-per-engine-hour for the maximum number
of engine-hours "from the cradle to the scrap- heap" at least possible
all-in costs, was being lost sight of
H. Holcroft (49-54) wrote: The Author's experience
of the lack of co-ordination between the Loco. Running and Shops is not typical
of conditions in Great Britain, and apparently things are better ordered
at Home than Overseas.
My experience began on the Great Western Railway and here the two departments
were under one head and were closely co-ordinated. It was, and no doubt is
still the policy to move a proportion of their officers from one department
to the other and back at intervals of a few years during their career so
that there are men with dual experience advancing to the senior positions.
New construction, alterations or modifications of existing locomotives receive
consideration from both aspects and design follows upon this. It is in fact
the Author's "heretical suggestion" in being, only the head of the department
is styled Chief Mechanical Engineer instead of Loco. Running Superin- tendent.
On the former S.E. & C.R., and in later years on the Southern Railway,
the two departments were separate but the Loco. Running Superintendent, although
independent, was responsible to the C.M.E. for maintenance of the locomotives
in service and to the Traffic Manager for their operation. Rigidly applied
the conditions did not make for anything like the same degree of co-ordination
as on the G.W.R., but actually things were much more favourable than they
might have been, due to two factors: the C.M.E. had wide experience of loco.
running and the technical staffs on both sides were in close contact on the
friendliest of terms, and it is my pleasure to record my experience of it.
Informal discussions were frequent and not confined to maintenance, but also
included design and performance. Such discussions were often followed by
visits to the sheds or runs on the footplate to get down to realities and
reach mutual agreement. Thus, under favourable circum- stances personnel
can bring about co-ordination apart from systems, whatever they may be.
My third experience, fortunately very brief, has been where the loco. running
is merged into the Traffic Operating Department and subordinated to it. Whatever
the merits may be on the operating side, my impression is that from the
professional angle it is psychologically wrong and unlikely to produce an
atmosphere favourable to close relations between the departments concerned
with the mechanical aspect when it is felt that one side has lost its
independence by the change.
Boiler and Firebox. In this case I disagree with the Author on the
type of boiler The taper boiler weight for weight can be larger in cross
section at the firebox tube plate, giving wider waterways and tube spacing.
The narrow front end, on the other hand, gives a much better view of the
road ahead, especially if the smokebox is flush with the clothing. There
is less disturbance of air with the smaller diameter of front and the chimney
projects further, so that there is less liability for smoke and steam to
beat down and obscure the cab windows. The welded firehole appears to have
advantages, but any firehole is liable to give trouble if there is not a
washout plug immediately above it to give access for removal of the scale
which accumulates on top of the firehole. The bottom half of the hole should
have a cast iron protective segment to take up wear of fire irons, etc. It
should be flanged to drop into place and not be fixed by studs.
Washout doors are preferable to plugs at the foundation ring and the Author's
mention of lead joints suggests that he is not au fait with up-to-date methods.
No trouble is experienced if the oval holes in the firebox shell and the
doors themselves are made to gauge and a flat woven asbestos ring impregnated
with graphite is used .. The joints are also standardized and checked by
gauge at the Stores, and any not conforming to limits are returned to the
manufacturers.
The advantage of the door is that it enables scale to be more readily removed,
and it gives a much better view of the water ways and stays. Washout water
escapes from a plug hole at some velocity, impinges on frames, cross-stays,
etc., and is liable to flood out axleboxes and other bearings. With a washout
door the opening is so much greater that the flow of water is slow, so that
it falls straight into the pit.
The Author advocates clack-boxes on the barrel with deflection plates to
divert the feed water from the tubes. This, however, subjects the barrel
plates to surface strain due to the great difference in tempera- ture between
boiler water and feed water temperatures. The result is that conditions are
created which are favourable to corrosion by oxygen, and pitting of the plate
may occur.
The most satisfactory way is to place the clack boxes on the side of the
dome, there being short internal delivery pipes descending from the clack
box to just below water level, an easy bend diverting the stream from contact
with the tubes. If water is chalky, these pipes will gradually make up, and
therefore they should be easy of removal at intervals for cleaning.
Regulator and Superheater. The multiple valve type of regulator may
have some advantage, but the retention of steam in the elements is not one.
The Author repeats the old fallacy that the presence of steam in the elements
averts burnt ends. Steam, when stationary, can reach a temperature at which
the metal will burn. It is steam in motion that carries heat away, and the
same applies to air from a snifting valve.
The suggestion that a very short elbow at the smoke box tube plate would
suffice to collect steam would be disastrous if tried in practice. The surge
of water to the front end which occurs on steep inclines, snatches at the
drawbar or in .heavy braking would be liable to wash over, and slugs of water
would break the cylinders. The safest place to collect steam is near the
middle of the boiler. The G.W.R. engines have an internal pipe extending
as far as the firebox tube plate, steam being collected from the front corners
of the belpaire firebox, the highest point, by two branches in a vertical
plane.
Smokeboxes. With outside cylinders the built-up box-like construe- tion in
steel plate supporting the smoke box and containing the steam and exhaust-pipe
connections is a great source of trouble. The false floor cannot be made
reliably airtight, and leakages of water passing through the sulphurous smoke
box ashes sets up rapid corrosion in the steamy atmosphere of the box. The
undesirable practice of filling-up the cavity in the floor of the smokebox
with brick and sealing it with a layer of Portland cement in the endeavour
to make it an airtight job presents the fitter who has to get it out with
an unenviable task, calling for a pneumatic road drill! Steam pipes, if not
welded at the flanges, should be re-rolled after being put in the fire for
setting or other reasons, otherwise they are liable to be blown out. The
steel pipe should not be carried below the level of the ash in the smokebox.
A short cast iron distance piece should be inserted in the region of the
ashes as the steel pipe will rapidly corrode and perforate in this position.
Annular blower rings and ejector exhaust incorporated above the chimney bell
are preferable to those situated at the blast pipe top, as the smokebox is
then clear of pipe obstructions.
The weak point of hopper discharge of ash is that grit in the valves leads'
to drawing of air, combustion of ash and consequent burning out of the apparatus.
It is better to form the smokebox bottom without pockets or obstructions
so that ash can be quickly discharged by shovel or pneumatic conveyor.
Boiler Accessories. There is a good deal to be said for the Weir type
of feed pump. While more costly than the injector to make and overhaul it
will run with minor attention from one shopping to another, whereas injectors
in many water areas have to receive frequent atten- tion for cleaning and
changing of cones so that much time and labour is expended. The degree of
regulation with the pump is far greater than possible with the injector,
and it will deal with hot water without any trouble. .
. Any advantage of top feed is offset by the liability of crusts of scale
on the trays to break off and fall among the tubes, where they cannot be
dislodged without withdrawal of tubes. There is no necessity to fit clack
boxes with valves in order to clean them in steam if the wings of the clack
valve are curved to a slight helix. This gives them a small amount of spin
and keeps both seats and guides free of scale.
In the case of gauge glasses there is much to be said for the G. W. R. practice
of an extension handle to close the gauge cocks in the event of a broken
glass.
. An objection to the Caledonian type of whistle is that it does not give
a distinctive note of warning from engines entering dock areas, being confused
with the medley of steamship sirens. The American chime whistle is preferable
if a change is required.
The sliding type of firedoor should be hollow, with air admission at bottom
and holes in the front admitting this air to the firebox. In this way the
doors are cooler and do not radiate so much heat into the cab. A latch should
be provided which when turned over prevents the doors from fully closing
and holds them some 2" apart and so leaves a gap for admission of more air
when required.
Cab. From my experience of their use the side-to-side operation of
the driver's brake valve is little or no better than the forward and backward
movement. The most sensitive is the valve on a vertical axis with semi-rotary
movement, as in the air brake. What is required, and much overdue, is a vacuum
equalizing admission valve analogous to the Westinghouse equalizing discharge
valve. The driver would then make his reduction by gauge and the actual admission
of the requisite amount of air to the train pipe would follow automatically
and in accordance with the length of train, thus relieving the driver of
deciding the matter by a series of reductions until the desired retarda-
tion is brought about. .
The application of the brake by the handle should cut off the small . ejector
from the train pipe and a lap position should be arranged in which air is
neither admitted to nor withdrawn from the train pipe. Extreme movement of
the handle should admit air direct to the train pipe in case of emergency,
in one direction, and full release in the other by admitting steam to the
large ejector.
The practice of combining the ejectors with the admission valve necessitates
its being placed where the ejector exhaust can reach the smokebox through
a straight pipe, either by carrying the pipe through the steam space in the
boiler, threaded through the stays, or outside the boiler and parallel to
the handrail. This limits the choice of position of the brake application
handle, with the result that the driver often has a massive fitting obstructing
his free movement and access to the cab window. The ejectors should be placed
outside the cab as on the G.W.R. and L.M.S.R., as this gives more choice
for placing the brake valve.
Windscreen wipers are not suitable on locomotives when mud drips from tunnel
roofs and splashes the windows. Use of wipers in this case merely smudges
the glass and makes matters worse. A water spray directed on the cab window
and deriving its supply from the injector delivery is much more effective,
as not only does it clear mud and dust, but removes snow and ice as well.
Padded seats are apt. to get dirty, oily, torn and generally unhygienic.
It is much better to have hardwood seats carved to suit the human anatomy,
and these should be rubber-mounted to take off harsh vibrations.
Duck boards are risky, as the corners of the strips quickly round off and
heels are liable to be caught. A chequered steel plate or cast iron floor
cause slipping if oil gets spilt, and some kinds of coal dust, when wet,
are slippery. A wooden floor is much the safest and is preferable, even if
it does involve some maintenance.
One point about cab floors is to have a really good fit with the firebox
back to minimize draughts and admission of dust from below. Any openings
in the cab front for spindles or handles should also be a good fit so that
in meeting a deluge of rain, water does not penetrate into the cab. Doors
between engine and tender add much to the comfort of a cab.
Frames. The front buffer beam should be bolted on so that it can be easily
removed for straightening if. bent in a collision. It is a long job to cut
out rivets and re-rivet.
Valve Gear. It may be observed that the design of gear shown by Fig:
lla is that in use on many of the Southern Railway 3-cylinder engllles.
Reversing Gear. If of the screw type it should be arranged with the spindle
vertical as on the L.N.E.R. This saves a lot of room on the driver's side,
and it is easier to operate.
Pistons, Crossheads and Rods. The use of a bronze nut will depend
on whether the piston. rod is solid with the crosshead or not. In the former
case, where the piston must be uncoupled from its rod a bronze nut is much
easier to move; otherwise, a steel nut is preferable.
Crossheads of the single bar type wear very rapidly, due to sand and grit
getting on the top surface of the bar, which is also a handy ledge for enginemen
and fitters on which to rest oil cans and tools which had previously picked
up dirt elsewhere. An auxiliary bar above the main bar reduces wear not only
by additional surface, but also by acting as a cover for the main bar.
As the Author remarks, side and connecting rods should be of plain carbon
steel. Alloy steels cannot be dealt with at the sheds if the rods are bent,
and sending them to the works holds the engine out of traffic for several
days.
The satisfactory working of piston rod packings is more a question of crosshead
wear. If this is allowed to develop no design of packing will be efficient
under the vertical play to which it is subjected.
Springs and Hangers. The Author's idea of avoiding fractures of spring
hangers is one of "brute force," that is, he advocates making them thick
and clumsy. In hangers of normal size tensile stresses are quite moderate,
and the fractures are due to fatigue cracks spreading over the cross-section,
usually at the threads. These are the result of variation of stress due to
the introduction of a bending moment. If the hanger is free to move with
the flexion of the spring no couple is set up. In order to give free movement
the knife-edge washers above the nuts should be carefully made and fully
case-hardened, so that the edges and groove can stand up and not be hammered
together with time.
Apart from this, in the course of time the spring adjusting nuts and their
lock nuts are difficult to move on the threads by reason of incipient seizure,
and the hangers may be subjected to considerable torsion in the process.
It is said that a coating of aluminium paint on the surfaces will prevent
this partial seizure by interposing a dissimilar metal.
Miscellaneous. Sand boxes on top of the boiler require a conveyor to fill
them. or an overhead bin. Filling by bucket is too laborious. In these days
of track circuits, heavy sanding of the rail by gravity is frowned upon.
Steam or air sanding is preferable in many ways. Ashpans with flat flooring
as recommended by the Author spill cinders on the track and cause fires.
The bottoms should be slightly ramped upwards towards the doors to prevent
this happening.
More important than fitting the front end of engine frames with shackles
is to see that there is a good place for the application of jacks without
involving a lot of dismantling. Derailments are dealt with far often er by
jacking than craning.
Tenders. Four rigid axles are preferable on tenders to the bogie type, provided
the wheel base is not excessive. Such tenders are simpler in construction
and in the absence of bogie centres permit of a well below the main tank.
The brake gear is also more straightforward.
The Author recommends the closing of the front of the tender by one long
steel cupboard, and this might well apply in the case of a self-trimming
tender with some 5 tons of coal stacked up at the front end. Most of the
12 tons of coal will have to be brought forward by hand, and the fireman
should have a gap which he can open by a door or the removal of loose boards
if he is not expected to climb over the tool boxes, a practice to be deprecated
while running. Some fo.rm of water gauge on the tenders is very necessary.
A simple and reliable way is to connect a short length of rubber hose to
a cock near the bottom of the tank. The pipe is hooked up when not in use,
with the cock open, and to ascertain the water level it is merely lowered
until the water overflows, so indicating the level inside.
Conclusion. There is no such thing as the Ideal Locomotive, and never will
be. Opinions differ so much on what is ideal. .
Meeting in Derby on 12 December 1945 chaired by J. Rankin
J.M. Jarvis (62) said the Author
recommended that the cab roof should be long and made from one piece with
the cab sides. It would seem that this might cause considerable difficulty
in attaching the lifting gear to the rear of the engine, such as in the case
of a break- down. It was also noticed that chequer plate was recommended
for the cab floor; whilst this would wear much better than the usual wooden
boards, would it not tend to be very slippery for the fireman? One further
point of interest was the position of steam collection suggested. It would
appear likely that trouble mlight be experienced with water getting carried
over into the collection elbow due to the boiler water surging forward,
especially when running on gradients. Admittedly, whilst braking or running
downhill the regulator would generally be shut, but the water could still
enter the elbow and the header, and so cause trouble when the regulator was
subsequently opened. Although the G.W.R. do not use domes, they position
their steam collectors in the front of the Belpaire box, where the water
level is reasonably constant.
R.G. Jarvis (62-5) commented on the Author's
remark that the 2-cylinder 4-6-2 was to be eschewed. This was a very sweeping
statement when one considers that this type was and probably remained the
most popular arrangement in the U.S.A., and many most excellent examples
of the type were in use all over the world-to mention one particular case,
the large South African Railways' Pacific type locomotive. Surely the objection
to the 2-cylinder 4-6-2 was not fundamental, to be condemned because some
South American Railways had trouble with one particular design, whilst the
"XB" class in India had got a bad name, possibly not entirely of its own
fault. He agreed that the Cartazzi control of the trailing wheels was a bad
feature but this was only one particular arrangement and not fundamental
to the Pacific type. In his opinion the 2-cyl.inder 4-6-2 could be an ideal
arrangement. for a medium sized mixed traffic, general purpose engine. The
2-cylmder arrangement had the advantage of simplicity with no crank a:cles
or inside big ends, eccentrics, etc., a point very much appreciated at runnmg
sheds. The type permitted of the use of a wide firebox, so important in countries
where coal is not of the best. The arrangement of the rear end gave much
greater freedom of design for the firebox, ashpan and self-emptying features.
With no frame envelopmg the firebox all stays could be repaired with the
boiler in situ and no steam-tight stays were required.
He agreed with the Author that the 4-6-0 type was a useful engine where good
coal was available, but the 4-6-2 was generally a far better riding engine,
with its fixed wheel base in the centre of the frame, and with carrying wheels
under the cab. . Another advantage of the 4-6-2 was that it lent itself to
the bar frame arrangement and here he disagreed with another of the Author's
points that frames should be of the plate type. Doubtless the Author had
.made this recommendation largely upon his experience of the relative damage
sustained by the two types of frame in the event of a collision, but there
was far more in frame design than the occasional question of collision, almost
however careless the Running Department might be.
Essentially the frame had to be a girder to carry the components of the
locomotive and to act as the main bed plate of the machine. He considered
emphatically that it should be rigid and not allowed to bend on curves, as
otherwise all manner of axle box, crosshead and other troubles came in. From
this point of view, from the point of view of. accessibility, and also through
the axial loading of all the suspension he considered that the bar frame,
properly designed, fulfilled all these requirements in a better manner than
the plate frame.
The Author's experience of bar framed engines had been unhappy but Mr. Jarvis's
had been very much the reverse. He had taken an interest in certain designs
of German origin during a period of nearly 12 months spent on the Turkish
State Railways in 1941-42, and had, reluctantly perhaps, to admit that the
big 2-8-2 and 2-10-0 classes of Henschel design and the smaller 2-8-0s built
largely by Nydguist and Holm, and Tubize, but which were actually a standard
German State Railway design, were very excellent engines. The Turkish State
Railways' tracks are well laid and engineered, but owing to the nature of
the country, which was almost entirely mountainous, conditions of curvature
and gradient were very similar to those obtaining on the Highland and Callander
and Oban sections of the L.M.S. The large 2-8-2 and 2-10-0 were bar framed,
the frames being slotted from the slab. They were developments of the plate
framed 4-8-0 supplied by Henschels some years ear her. The frame repairs
on the bar framed engines were practically nil except for a slight weakness
at the saddle, which had been rectified, but the 4-8-0s were a mass of patches,
welds and twisted suspensions. It is, of course, true that the 2-8-2 and
2-10-0 were not more than 3 or 4 years old and troubles might develop later.
On the other hand the bar framed 2-8-0s mostly had steel cast frames and
these engines had been running under most arduous conditions since about
1928. He had seen many of them passing through the Sivas Workshops for general
repairs, and had seen only one case of a defective frame, which was the result
of a very severe collision. The only damage sustained in this case was the
bending of the front legs of the frame, and this was rectified in a way which
was perhaps primitive but nevertheless effective.
The most illuminating example of the resistance of the bar frame was the
case of one of the big 2-10-0s which was in head-on collision between Ankara
and Kayseri early in 1942. After the collision it toppled over the embankment
and rolled down .a slope of .about 30 ft., finishing with all wheels uppermost.
A branch line was built to retrieve the engine, which in due course reached
Sivas, an ugly, dlshevelled mass of twisted iron, but running on its own
wheels. The engme was brought into the light repair shop, where the damaged
details were burnt off, straightened and welded on agam. As an after thought,
the engine was un-wheeled and being found to be in good order so far as frames,
wheels and boxes were concerned, she was wheeled and sent back into service.
He dreaded to think what would have been the condition of a plate framed
engine in similar circumstances.
A pressure of 50 lb. per sq. inch in the lubrication. system. did appear
to be rather high, and now that the 011 was bemg injected mto the axle box
keep instead of the top of the axlebox, he thought that some consideration
might be given to putting the non-return valve at the pump end of the flexible
pipe and thus avoiding pressure in this pipe.
The American engines running here during the war used a very special block
with hard inserts which were probably expensive to manufacture. Shrouded
blocks had something to recommend them, particularly on lines with sever~
curves . .Double brakeblocks were being used on several types of engmes and
this would reduce the amount of changing in the Sheds. The screw controlled
ashpan dampers had quite a lot to recom- mend them since a more variable
opening to the ashpan .door could be obtained by their use. They were, however,
a little more complicated and could not be operated with the same rapidity
as could a normal push and pull gear.
The Author favoured the extension of grease gun points to pin joints. Due
to the small size of the grease nipples, was there not a danger that they
might be overlooked if used extensively? Had the Author any comments on other
features of American design, bar frames, for instance?
J.C. Loach (65) (in a written communication) stated
that when discussing the general type of locomotive, the Author's first two
sentences implied that the 2-cylinder 4-6-2 was not such a successful type
of locomotive as the 3-cylinder 4-6-2, because of the different number of
cylinders. Apparently the Author still held the idea that the steam load
on the cylinder cover and out-of-balance masses, first on one side of the
locomotive and then on the other, were causes of nosing. It was usual in
engines 50 or more years ago, when their weight was not great and their length
was short, but with a 4-6-2 engine of, perhaps, 90 tons weight and 45 feet
long the period of nosing was not directly connected to these fore-and-aft
off-centre-line thrusts when she was running at 400 revolutions per minute.
The solution lay in proper and effective controlling arrangements in the
bogies and trailing axle unit. He suggested that the Author had considered
locomotives in which there were a number of differences in design and he
had inferred that the defective feature was due to one difference, whereas
it was really another. He regretted it, but it was so easy to draw incorrect
conclusions when so many differences in the designs occurred.
One detail not mentioned in the discussion was the spring. The Author suggested
that nibs were frequently the cause of broken plates. He agreed, but thought
the central rivet hole was even more frequently the cause of fractures. Both
were avoided by using rib-and-groove section for the plates and by having
a button to locate the plates in the buckle. Nevertheless, whether the springs
had a central rivet fastening or a button, it was understood that more than
50 per cent. of those changed at one large shed in this district were due
to the plates moving through the buckle. There was no known reason to believe
that this was not typical of what existed at other depots. The cause of the
trouble-and here he dared to be as dogmatic as the Author in his paper-was
that the spring links were used in compression. If brackets were fitted to
the frames so that the spring links were in tension, a self-centring tendency
would completely eliminate the trouble. Although the solution involved a
little more initial expense and a little more weight being added to the engine
than the other (links in compression) arrangement, he considered that these
items are outweighed handsomely by the saving at sheds and in spring repairs
throughout the life of the engine.
R.S. Hall (65-8) (in a written communication)
stated that it was plain that the Author based his criticisms on that very
important factor-the elimination of unnecessary or avoidable time taken up
in shed repairs and examinations, especially at times when the demands of
the Traffic Department for motive power exceeded the supply; his paper was
highly controversial and without doubt all the better for that, as the resultant
discussion proved. 00 In .the paper there were very few engine details that
remained unrnentioned, but one that came to mind was the thermic syphon in
the firebox which, of course, was welded to steel firebox plates which the
Author so whole-heartedly advocated. It would appear that thermic syphons
are well thought of m one East African Colonial Railway, and he referred
members' attention to a letter on this subject published in "The Engineer"
issue of November 16th, 1945. The comment on fusible plugs was interesting,
although one would hardly expect a long parallel small hole as illustrated
in Fig. 3 to be satisfactory in service; It was generally hoped that these
safety devices are never required to function and so if in use for a long
time without blowmg It would seem that the lower end of the hole-with the
metal in it-would become so corroded that the plug would fail to act when
the necessity arose. It was more general to have a bell-mouth at the lower
end as well. which is not filled with metal. Perhaps the Author omitted this
detail from the sketch, concentrating more on the taper thread, which was
his main point. Some years ago the design of fusible tin boiler plugs was
investigated by the Bureau of Standards, U.S.A., and m Paper No. 53 it was
recommended that "The bore of the plug be tapered uniformly from end to end
and be filled the whole length with tin, and plugs to be fitted with !he
small end of the bore exposed to the fire, with the other end one inch above
the water side of the plate." This, no doubt, was also controversial and
he would add that the paper in question related to marine boilers.
Referring to the fit of smokebox doors, the use of circumferential clamps
implied the use of a spanner, which was not so convenient as the centre dart
and handle. The doors were usually pressed and then machined on the bearing
edge and as this edge bedded on to a machined door ring on the smoke box
front an air-tight joint should be made by means of the centre dart; he was
of the opinion that the rivetting of the ring to the smokebox front and also
of the hinges to the door itself produced some distortion which was difficult
to eliminate entirely and so there seemed to be some justification for the
Author's preference for the old Midland type of fastening.
The Author's comments on driver's brake valves were most interesting and
having had experience with both the types mentioned he could well appreciate
the suggestion to combine the L.M.S. type with the Dreadnoght ejector; one
possible objection came to mind, and that wvas the. resistance to be overcoma
when the large ejector is brought into action. For crosswise operation of
the brake valve with a bent arm a back-handed movement would be necessary
when releasing the brakes, as presumably the hand of driver remote from the
cab side would be used for brake application whether the engine was right
or left hand dnven. For application wiIth an almost straight arm giving the
best purchase, the combined brake valve fitting would have to be located
somewhere near the middle of the boiler front plate, by no means the best
position, except perhaps with a broad gauge engine.
The next item of interest I note is the sliding type of firehole door and
providing the door leaves are so fitted that sliding is free and they do
not require coaxmg to open or close I am in agreement with the Author but
must admit to a liking for the top hinged type of door as used on the Indian
State Railways and which acts as an excellent air deflector as it opens inwards
but should be designed so that the door will come up at least to the honzontal
position; the projecting balance weight and handle is not usually considered
objectionable. In the Author's sketch of his ideal cab arrangement he noticed
that he showed the roof ventilator hinged at the back; he may have some special
reason for admitting air from the front but for fast runmng this arrangement
did not seem so satisfactory as that fitted to tropical Colonial locomotives
which had a double cab roof, the. inner one. of timber, with an air space
between the two and a ventilator opemng upwards at the rear.
He noticed that the bronze piston head nut was considered most undesirable,
but as no reason was given except by inference (sla:kening back) he would
be interested to learn if there were other objections. The Author would probably
approve the M.O.B. type of piston and rod as developed by Wota Ltd. (A.B.C.
Coupler Co.); this rod has a double taper at the piston end covered. by a
plate permanently fastened to the piston head by countersunk rivets, the
whole machined flush after assembly.
In respect of laminated leaf springs, there was no doubt that the majority
of cracks in spring leaves emana!e from cen!re nvet holes or nibbing, any
interference with the full section of a spnng plate must of necessity be
a weakness, and it would appear that Messrs. Wm. Gnffiths Ltd., of Sheffield,
have so far provided the best answer to this problem. They had a patent spring
buckle fastening which was pressed on. to the assembled spring leaves, the
rounded edges of which, for the wldth of the buckle, were ground flat; no
end movement was then possible, and each spring plate retained a full rectangular
cross-sectional area. In dealing with the lubrication of valves and cylinders.
he was sorry to see that the Author leaned towards the American type of sight
feed lubricator instead of the Enghsh Eureka lubncator, and he wondered why
the latter should be hotter when in use, as both types work on the hydrostatic
displacement principle, using boiler steam. Valve and cylinder lubrication
was a matter of much interest to him some years ago, and he still. retained
a liking for the forced feed mechanical lubricator; he admitted that its
application sometimes left something to be desired, but he was firmly convinced
that this was due to too much attention having been bestowed on the design
of the pump itself, which without doubt had reached a very fine state of
perfection, and not enough to those most important adjuncts: the non- return
valve at the far end of the oil feed pipe and the dnve to the mechanical
lubricator. For condensed steam to find its way into the lubricator as mentioned
by the Author, some serious defects were indicated but it was true that water
would often find its way into the feed pipes and so interrupt the uniformity
of the oil feed; but this state of affairs could only be caused by two things,
means of .mgress into the pipes from the cylinders.or valve chest and at
irregular intervals a drop in pressure in the oil pipes permittmg this inrush
of steam. For this same reasons the regularity of feed drop by drop wiIth
hydrostatic displacement lubrication may by no means be that indicated by
passage of oil drops througyh the sight glasses
Lt.-Col. J. Blundell (68-71) (in a written commication):
all designers should consider the locomotive as it was seen in an ill-lighted,
cold, wet and dirty shed, without the specialist departments, tools, and
tradesmen found in the shops. It made all the difference working on an engine
all round the clock, always against time, in very uncomfortable conditions,
compared with mainly day shift work in a comparatively well-lighted and heated
workshop, with the best and latest equipment at one's hand. These different
circumstances accounted for the" Great Gulf." Much closer liaison was essential
between the designer-manufacturer and the user, and it was not to be obtained
by a few periodical visits and trips, or by the mere use of the dynamometer
car, or even by the perusal of unfeeling reports and statistics, valuable
as they may be. Above all, the engine crew must be considered, and more done
to keep them better informed and increase their technical outlook. The
present-day system of the " Mutual Improvement Class " did not meet the case.
His civil and military experience had convinced him that the new work engineer
and technician was not interchangeable with the maintenance engineer and
technician. New work personnel was more easily trained and reached experienced
maturity very much sooner than maintenance personnel, which required much
longer experience to become really efficient and reliable. Both. however,
must be provided, and the more each realized the other's difficulties, the
better designed and more economical working, reliable, and accident-free,
will the locomotive become. The running shed personnel, however, did tend
to be too conservative and old-fashioned He welcomed a go-ahead, virile and
young shop personnel to combat this failing. The shops on their part, must
play the game and grant the sheds the customer's privilege of being, shall
we say, very often, right.
The Author's choice of types was good, for general work a two- cylinder,
outside, engine. It was easier maintained and inspected on the level, a great
benefit to its crew and the shed staff. He would, however, like to see a
good 0-6-0, or 0-8-0, tank shunting loco. In this country with its many large
yards much time and temper were wasted in heavy shunting with under-powered
engines, or by keeping main line engines back for this work. Such tank engines
should be three-cylindered to give good acceleration, and have reasonable
coal and water capacities, and a reliable power reverse. Under some special
circumstances the diesel engine was the answer, but when used it must never
be overloaded.
Boiler washing plugs must be better considered, they should be placed after
consultation with the sheds, and if necessary replaced after experience with
the prototype of a class. The necessary use of rods, and visual inspection,
were generally very difficult or even quite impossible once the boiler was
in the frames. After much varied experience he held that the taper fusible
plug was the most desirable.
If a ratchet arc on the regulator was provided, place the ratchet lever on
the push side of the main handle grip. He had seen several accidents on U.S.A.
locomotives where the ratchet lever had to be pulled towards you at the same
time as the main handle had to be pushed away to close the valve. He suggested
that main steam pipes should not be in the main compartment of the smokebox,
which should have nothing but blastpipe, cowls and any necessary exhausts,
with a smooth floor flush with the bottom of the main door or separate ash
drawing door. Could not the steam pipes and header be placed in segmental
compartments immediately in front of the tubeplate with external covers.
All fastenings to be made from outside except the main header joint. Elements
could be fixed with a bolt passing right through the header with the nut
on the top inside the outer cover plate of the compartment. Steam pipes could
be of oval section if necessary to give clearance for the outer rows of tubes.
All boiler accessories should be changeable on the level in ten minutes and
replacements held at the shed for last-minute emergency changes. The water
valve control of some W.D. locomotives was so designed that the whole rodding
up to the actual handle bracket had to be stripped to change the plug cock
which was seized owing to being bulged by frost. Dismounting alone took a
fitter forty minutes. Actually he preferred top feeds properly maintained.
He would, however, like to see injector feed pipes brought up to a clack
box on the face plate, and continued by an internal tube passing through
a plus hole in the plate so that it could be withdrawn entirely when it became
choked by merely dismounting the clack box. A new feed pipe could then be
fitted at once and the old one cleaned in the shed shop. The internal pipe
in this case must be reasonably straight and secured at its leading end by
an easily reached clip under the dome or top boiler manhole. The steam manifold
should be outside with the sterns of the valves passing into the cab, and
the valve wheels fitted with clear enamel plates specifying their purpose
with an arrow showing the shut-off direction of turning. He advocated a return
to the good old "Dog Chain" whistle control, the usual modem contraption
is a thorough nUisance. Hot water injectors soon cease to function as such
with temporary hard water, the sliding cone furs up solid in a few hours.
InCidentally, D.M. boiler enamel is the perfect answer to this trouble under
field conditions. .
The brake controls should be carried across the cab on all engines, many
claims are due to this not being the case. It was far more necessary to stop
the engine from both sides than to start it.
Sanding, cylinder cock and rocker gate controls needed more care In design.
He had seen an engine on its side owing to the cock gear over-opening and
passing the centre on a bell crank arm. It jammed at a critical moment, causing
the driver to divert his attention just when. it did matter. All joints should
be grease-nipple lubricated, especlally the fulcrums of the levers. Rods
should be light round tubing, and not flat strip, and should be placed so
that they can be both seen and got at, and not so that they get nipped between
the frame and fireebox. All crank connections must be fork-ended with a collared
pin screwing up tightly to one leg of the fork, nutted and pinned.
"Better cabs, better enginemen," was a good slogan, and he advocated a roomy,
easily cleaned, sheltered cab and a clean plastic or wood-lined clothes locker;
they were often going to lodge and wanted a clean turnout when they got in.
The locker floor should be flush with the door opening to allow cleaning.
The tool locker wanted the same consideration. Much had the old, dirty, wet
tool locker contributed to delays and failures. Put recesses for the oil
bottles, and clips or trays for a proper tool kit. Make the tool kit part
of the engine, it should never have to be carried about, and thrown down
on the stores floor, ballast or footplate several times each day. No man
did his best with discouraging tools. Open cabs were best in this country
three hundred days a year, but the remaining days required windows, if accidents
were to be avoided. On too many engines the driver's coat was wired up for
a wind breaker, and spongecloths, waste or newspaper filled the all-too-many
holes in the sides and floors of cabs in an endeavour to keep body and soul
together on a cold night run. We could do better for the enginemen, and taken
all round they deserved it. Personally, he disliked a chequerplate cab floor.
He doubted the necessity for running platforms in this country, the restricted
gauge ruled them out. They did require better footsteps and general accessibility
to the front end, motion and tenders. Let them have proper non-slip treads
to steps, and a plastic covering to all hand- rails and handles generally.
In regard to cylinders, they should be designed so that pistons and valves
could be inspected and drawn without requiring an acetylene burner, or removing
a hundredweight or so of other gearing, or even removing the whole front
buffer beam. These things had to be done in the shed. Nuts should be easily
reachable with an effective spanner, preferably a box spanner, and the fitter
should have room to use his bar. Give him space to fix a pulley tackle where
the part was heavy, and a suitable attachment to lift the part, or fix a
lifting eye if required. He did not like the U.S.A. necked studs, and preferred
a cover with a centre easily fractured, so that the least weight possible
came adrift, should the unexpected happen: let most of the weight remain
fixed.
Many of the suggestions for valve gear deserved consideration. Personally,
he would like to see the poppet type developed and per- fected. Poppet gears,
when good, were very good. The sheds must advance and be able to deal with
these types of gear. If diesels were coming, as he hoped they were, running
sheds would have to go in for higher grade fitting, equipment, and layout,
in any case. Poppet gears could very well be dealt with in the diesel shop.
Screw reversing gears were certainly the best, and preferable to unreliable
power operated gears, but a special case should be made, as previously mentioned,
for shunting engines, the screw gear was too slow, and involved the driver
in crossing the footplate at times. All shunting engines in large yards should
have right and left hand, dupli- cated throttle, brake and reversing controls.
The cost would be saved in time, and claims for damage, to traffic, and damage
to stock. He considered that the crosshead was too often a weak spot. The
rod end was too frequently forced into the crosshead when the engine had
been "working hydraulically." He had experienced much trouble With crosshea~
cotters. fitted, as is now a standard practice, with no draw for refitting
.. This made it necessary to send the assembly back to shops after a mishap.
If a cotter with draw was fitted, the cross- head could ~sually be refitted
in the shed, and much engine availability saved. Havmg to send such repairs
to shops robbed the shed of valu- able po:ver, often when most needed, as
it was invariably the case that these. mishaps occurred .mostly when everyone
and every machine were workmg all-out. The nsk of poor quality fitting at
the shed should be remote, and the sooner sheds were trusted to do this sort
of work the better for efficiency.
Stiffening-up springhangers was begging the question. They were quite heavy
enough. The fault lay in the rocking washers which did not rock. Instead
of approximating to knife edges, they more nearly approached a ball and socket
joint, which needed to slide instead of roll. Allow rollmg and proper rocking
to take place, and most trouble would vanish.
In connection with brakes, all running joints in the pipe work should be
eliminated and the joints made with modern connections of the cone and socket
type, or flanges where there was no room for end clearance to get cones up
and down. Above all, sectionalize the pipe work so that it may readily be
taken up and down as often as required for inspection, or more often still,
to give ready access to other parts of the engme s anatomy. -r:he best brakeblock
was that with one single heavy lug, and not two lighter ones at the sides.
Although heavier a double cheeked han"er, and single lug block, gave longer
life, and went a long way to obviate that most troublesome feature of the
single hanger type splaying out sideways. Many an expensive failure had been
due to this trouble. Single lug blocks wear to the bitter end and never break
away sideways.
Finally he said he would like. to pay a tribute to Mr. J. G. Robinson, of
the old Great Central Railway. It was very interesting to see many of his
ideas re-suggested in Colonel Tophams very valuable Paper. Robinson liked
to be,able to say, and could do so in very many of his designs, that It was
A Sound Running Shed Job " This should be the aim of all designers.
Meeting in Manchester, 14 January 1946. 74-
Third Ordinary General Meeting of the Manchester Centre held at the
College of Technology, Manchester, on Monday, January 14th, 1946, at 6.30
p.m; chaired H.H. Saunders
Saunders (74-5): The Author in the beginning of his Paper said there
was a great gulf between the loco. Runnmg people and the shops. In his view
this ought not to be the case. If, however, there was a great gulf between
the loco. Running and the. shops on any particular railway there was certainly
something amountmg to an ocean between the locomotive running people on an
overseas railway and the actual designers and manufacturers in this country,
and closer collaboration should be established.
The Author suggested that the boiler should have a good size Belpaire box
and let the boiler be big enough for the engine and a bit more as well. Designers
know what the correct size of boiler should be to match the performance of
the engine, but they seldom get an opportumty of incurnng the size of boiler
if this is necessary, as in nine cases out of ten they are given a basic
design to work to and asked to add a lot of items which alone will increase
the weight above that specified.
Bar Frames. He could not agree with the Author that "the frames should
unquestionably be of the plate type and not bar." He saw no reason whatsoever
why bar frames should have a weak front end. It seemed probable that the
Baldwin 2-8-2 that collided with the L.M.S. 8F in Persia was built in the
first place to take the American couplings, and even if the Americans knew
something about side buffers they had no idea that boxing contests were arranged
in Persia for the amusement of the troops. Beyond a certain size a satisfactory
engine can only be built around bar frames, which help in the design of the
firebox, eliminate horn blocks, and provide better rigidity as regards side
stresses. Much of the difficulty with some of the "X" Class engines in India
would have been avoided had the engines been designed around a bar frame,
when racking plates, double horns, and elaborate horn clips would have been
unnecessary.
There was one item which he thought the Author might reasonably ha ve included,
and that was the necessity of renewa ble items such as steel hub liners,
crosshead slipper blocks, axlebox liners, etc., being made and drilled from
properly manufactured jigs manufactured on a jig borer. If he was ordering
an engine he would insist on getting his inspectors to check over the jigs
before they were put into use.
W. Paterson (75): In 1895 John A. Aspinall used him,
then a lad, to stand in front of a full-sized cab built with every fitting
that would be on the proposed locomotive. He had to stand at varying distances
to make quite sure that the visibility and sighfing distances from the cab
were quite right due to the windows being repositioned, as the locomotive
had a Belpaire firebox, one of the first to be adopted in this country. He
placed a seat for the driver and went to the trouble of measuring all the
driver's and fireman's manual movements on the footplate. So far as he knew
that practice had been continued. Even then Sir John invited drivers, firemen,
Running shed fitters, not to mention a few Loco. Superintendents, to examine
the cab and to make comments on it. That was about 1895. His Running experience
began in 1899. He was never conscious of any obstacle such as the "Great
Gulf" the Author mentions, but he had the responsibility for years of upwards
of 3,000 main line locomotives, including 60 a day which were timed at over
60 miles an hour, and the supervision of thousands of footplate men, and
he thought that he knew something about a Running shed point of view. Well,
that was rns first experience of a C.M.E. That very well known C.M.E., George
Hughes, sent him a questionnaire, including 90 separate questions on a parhcular
superheater in which he was interested and an instruction to be at his office
in three days. When he arrived there, to his surprise (here were four other
of his colleagues, who had also had 90 questions to answer, and when they
got to the office, those 90 questions had been tabulated and classified in
their own names. and they had to explain their own comments on that particular
superheater and comment on what the other men said. It seemed to him there
was not so much of a gulf there. The same C.M.E., as a matter of interest,
after scrutinizing the recorded instances of locomotive failures in service
from any cause set up a battery of Committees comprised of District Loco.
Superintendents, and he divided the locomotives up and allocated each part
of the Locomotive into Sub-Committees, and a report had to be made on any
failures m six months. Do you know that nearly every recommendation made
by those Committees was adopted as standard and future practice. He never
remembered a single instance where he had any difficulty in obtaining access
to the builders of the locomotives which it was his privilege to use. Sir
Nigel Gresley invited him to discuss one of his latest creations from the
point of view of the Running Shed Man, and as a final example of shop and
Running shed collaboration, Sir W. Stanier personally discussed his L.M.S.
engines with representatives of the' Running shed staff, even down to such
precise detail as the number and position of every washout plug, and during
construction arranged for shed fitters, boilersmiths, engine drivers, and
firemen, as well as supervisors, to see the engines being built in the L.M,S.
workshops and make comments thereon. It is only fair that they should prevent
the impression spreading that the C.M.E.s were inaccessible, even to a humble
man like himself. One more point. It did not appear that the average shopman
was any worse off for his lack of running shed experience. It was infinitely
more important that as a shopman he should specialize in his own class of
work. Specialization was surely a basic essential in Running shed practice,
as it was in workshop practice. The range of machine tool equipment at Running
sheds depends upon a number of variant factors, including geographical positions,
transport, and so on. Personally, he was never happier than when there was
not enough work for the wheel drops and the machine tools at his depots.
He had charge of 97, covering the whole of the western Division (L.M.S.),
He thought that the ideal axle box would be better if it were round topped.
He would like to think that some future C.M.E. would substi- tute rotary
for all reciprocating parts. Then he thought they should be approaching the
Running man's ideal locomotive,
G.C. Marsh (76) said he was particularly interested
in that part of the Paper dealing with ejectors and steam brake valves. The
Author stated his preference for the Westinghouse type both on the score
of performance and simplicity, Westinghouse ejectors were, of course, practically
unknown in this country, and very few people here have ever seen one, but
he understood that this ejector incorpor- ated five separate jets with their
attendant steam valves, and could, therefore, hardly be described as simple,
As far as performance was concerned, that was purely a question of the quantity
of steam one was prepared to use. Ejector makers could provide jets to suit
any specification the railway authorities were likely to lay down. Many Railways
had very definite ideas in this connection. Coming now to the steam brake
question, he could not agree with the Author that the old Midland type was
the last word in automatic steam brake control. It was a most delicate brake,
but not in the sense intended in the Paper. The delicacy was required in
manufac- ture and assembly in order to get it to function sufficiently well
to pass muster on the steam test stand. On a train it always applied the
steam brake during vacuum applications but when release took place it invariably
released the engine brakes from "full on" to "full off" long before the train
brakes were released, thus allowing the engine and tender to give that sickening
lurch so well known to passengers, particularly after signal checks when
the train had been slowed down and was startmg to get away again. this was
particularly noticeable on long trains and had led on occasion to the engine
and tender parting company with the train.
Nowadays, modern steam brake valves were available which really did graduate
the engine brake cylinder pressure in accordance with the tram pipe conditions,
not only in application, but also in release. Such valves also gave the driver
an independent hand- operated graduated control of the steam brake. He did
.not agree with the Author that sight feed lubricators were the most suitabl.e,
as at the present time mechanical lubrication was gaining rapidly in favour.
The check valves on the feeds to cylinders should be of the diaphragm type
when mechanical lubrication was employed. He would point out that the trials
of ejectors in South America to which the Author had referred, took place
some 10 years ago: Since then they. have had some progress in this country
and completely new types of ejectors were now available which would put up
a very different performance . In fact, thossands, of the new type ejectors
were fitted to all the British and Amerncan Austenty engines, which, strangely
enough, recelve no mention in this Paper, although the German equivalent
engme was fully described. Finally, the "trigger" type steam brake valve,
of whatever form, was obsolete, and all modern locomotive designs incorporating
steam brakes employ graduable type valves, again incidentally fitted to all
the Austerities.
J. Hadfield (77-8) said he would most
certainly agree that the Running Department should be consulted regarding
matters such as train loadings, speeds, etc., but he was equallyy certain
that the average Running man did not possess either the time or the highly
specialized knowledge such as would enable him to become a successful locomotive
designer.
As recently as January 2nd of this year E.S. Cox read a Paper before the
Institution in London entitled A Modern Locomotive History, and he made
particular reference in that Paper to the stultifying effect which the Operating
Department of the L.M.S. exerted for a number of years. Regarding George
Hughes, Cox referred to what he termed the C.M.E.'s misfortune in having
to work with an Operating Department which strongly resisted proposals for
new designs for large engines.
The Author referred to the riveting of crown stays by first heating the head
ends of the stays by oxy-acetylene flame. Quite frankly, he could not understand
this, as to the best of his knowledge such stays were cold-riveted in this
country, and the question of overheating therefore did not arise.
The Author's reference to the multiple. valve header having the great advantage
of retaining steam in the elements at all times was not always true, since
it was standard practice on the South African Railways to arrange the multiple
valve regulator on the saturated side of the header.
On page 8 the Author referred to the position of the steam outlet from the
boiler. He could not agree that it was good practice to dis- pense with the
dome. In his view the higher the steam outlet was above water, the better,
and in the case of the particular engines mentioned one wondered to what
extent the superheater was acting as a steam dryer. Could the Author say
what degree of superheat was attained on these engines?
The statement that a steam temperature of more than 300° C., i.e.,
572° F., was undesirable, was not borne out in actual fact, since final
temperatures in the region of 700°F. are commonplace to-day, and no
difficulty was experienced providing the metallic packings and lubrication
arrangements were suitably designed.
The reference to the positioning of the steam turret on Garratt locomotives
seemed to be out-dated since for a long period of time the steam turrets
had been placed outside the cab.
Referring to the outline of the tender shown in Figure 16, one would have
thought that the Running Department would have insisted that an ideal locomotive
should be fitted with a self-trimming coal bunker, which was certainly not
the case in the design illustrated.
B. C. McPherson (78) suggested to the Author the
use of a self-cleaning smokebox of a type similar to that used on a number
of the modern L.M.S. engines which were giving good results and kept the
smokebox very clean.
The proposed cab with a large opening in each side did not appear to be ideal
for use in this country, and would undoubtedly evoke considerable criticism
from engine crews in bad weather, particularly when standing or shunting.
The provision of a running board round the engine seemed to be of no great
advantage as it should not be necessary, nor was it advisable, for a driver
to walk round the engine whilst it was in motion, and would merely reduce
the width of the cab and particularly the size of the cab windows, a feature
which was often a great disadvantage on modern locomotives with large fireboxes.
Needle bearings were a fitting which gave good results provided they were
located at points where the motion was purely rotary, but were not altogether
satisfactory for valve gear, since this condition did not obtain, and seemed
to be rather out of keeping with the Author's desire to provide a locomotive
that was economical to maintain.
Referring to the tender, the Author presumably did not intend to use a water
pick-up arrangement, and if that was so, there seemed to be something in
favour of the side filling lids for the tank. If, however, a pick-up was
used considerable trouble was likely to be experienced in keeping the lids
fastened due to the pressure generated inside the tank when picking-up water.
The Author recommended the fitting of castle nuts everywhere, and such nuts,
when correctely fitted, were certainly efficient, but there was the tendency
for fitters, should the pinhole not register correctly when the nut was tightened
up, to slack back the nut to the next castellation for easy fitting of the
split pin, which was a potential source of trouble in service, and for that
reason the use of spring washers or nuts of the Simmonds pattern would probably
be more satisfactory for general use, since these nuts could be tightened
easily when any looseness was apparent.
D. Patrick (79) said: The Author's statement in the
preamble that "what is required is an engine to run a maximum of train-miles
at a minimum of repair expenses," coupled with his declared aversion to
fuel-saving devices, may be all right on Railways which are not troubled
by competition from other forms of transport. On very many Railways, however,
the overall running costs, including repairs, are of first importance, and
the efficiency of the steam locomotives as a power unit must continue to
be improved by all reasonable means or eventually give way to other forms
of motive power, and considerable use of fuel-saving devices must be made
to attain the desired improve- ment in overall efficiency. He suggested that
improvement in design of the locomotive and all its accessories should receive
constant attention. Another point was that for a valve travel of 7" suggested
by the Author, he advocated a plain circular valve spindle guide. While
appreciating the simplicity of this item, it appeared that that arrange-
ment was cumbersome for such a travel, and introduced a bending action on
the valve spindle when in full gear, due to the angular thrust from the valve
rod. The modern crosshead type of guide eliminated this and also gave a lateral
stability to the valve gear which was not provided by a circular guide. The
German arrangement mentioned wherein a swinging link was employed in place
of a guide introduced an additional pin in the gear and also a bending action
on the valve . spindle due to the angular movement of the short link connecting
it to the swing link.
Regarding the self-trimming bunker suggested by Mr. Hadfield, which the Author
thinks might be an additional complication, surely there was no comparison
between firing an engine from a well-designed self-trimming bunker as compared
with one in which it was frequently necessary to move the coal forward by
hand to within reach for firing.
erred to the cab sketch on page 15, where a hinged skylight opened upwards.
Unless the cab roof was well clear of the gauge there seemed little
doubt
Cox, E.S. (Paper No. 457)
A modern locomotive history: ten years' development on the L.M.S.
1923-1932. 100-41. Disc.: 141-70; 275-6. 9 illus., 14 diagrs. (incl. 9 s.
els.), 11 tables.
Major paper in terms of steam locomotive history: it generated a
considerable amount of discussion, and therefore needs to be read in association
with Cox's Locomotive panorama. Several unfulfilled projects are
considered: a Hughes design for a Flamme type 4-cylinder 2-10-0 (Fig. 2);
a 1924 design for a 4-6-0 based on the compound 4-4-0 with a boiler which
Cox considered led to the Royal Scot type (Fig. 6). Figures 7 and 8 show
the Fowler 4-cylinder compound designs for 4-6-2 and 2-8-2 and Fig. 9 shows
the cylinder layout to have been adopted. A notable feature was the proposed
large combustion chamber. Long lap valve gear would have been employed. Cox
considered that the problem of incorporating a large compound within the
British loading gauge had been solved (this assertion does not appear to
repeated in Locomotive panorama). The four-ply frame construction at the
back end of the trailing truck was incorporated in the later LMS Pacifics.
Cox claimed that some cylinders were actually cast. Fig. 11 shows the starting
valve fitted to No. 10456, a Hughes 4-cylinder 4-6-0, rebuilt as a compound
in association with the Pacific project which was "the most modern but least
known compound engine to run in this country" (he appeared to forget that
the Gresley high-pressure locomotive was a compound). Fig. 12
(graph) showed annual coal consumption in the period 1927 to 1938
for 4-cylinder 4-6-0 (1929: 53lbs/mile; 1933 60 lbs/mile); standard compound
(1927: 44 lbs/mile; 1937: 51lbs/mile); Prince of Wales (constant
52lbs/mile), Hughes 4-6-0 (constant 60lbs/mile) and class 2P 4-4-0 (47
lbs/mile).
T. Henry Turner (151) said the Author's paper helped
us to study the way we had come, with a view to our deciding where to go
from here. After considering what had been done in other forms of transport
as a guide to what -night have been done with railway steam locomotives,
he concluded that liquid fuel, high speed engines, rotary motion and reduction
gears stood out as a challenge. It was notable, therefore, that the paper
referred to no experiments to replace crude run of mine coal during a decade
when ships, buses, cars and aeroplanes turned to liquid fuels. Perhaps the
next paper before the Institution would make it possible to follow two other
such features-rotary motion and reduction gears-on the L.M.S. turbine
locomotive.
D.R. Carling (154). The graphs of coal consumption
are certainly interesting but would pe even more interesting had it been
possible to plot Ibs./ton-mile instead of lbs./mile. Nearly all the curves
are concave with minima in the worst of the slump years, possibly due to
lighter loading. Can the Author remark on this feature?
It is by no means certain that the Author's conclusions about the deterioration
of compound performance would apply to the proposed larger designs, such
engines being unsuitable anyway, compound or simple, for secondary duties;
nor might it apply to compounds of more suitable design. Surely the correct
policy is to educate and train the staff up to the best possible design of
locomotive, not to .design the locomotive down to an under-trained staff?
It is an arguable point, too, if locomotives should be kept in service in
unsuitable duties. With ever-increasing utilisation the modern locomotive
may well have completed its economic life before it is really obsolete for
its original duties or something not much different.
This raises the question of repair costs. Has any allowance been made for
the age of the various locomotives and classes, as repair Costs usually tend
to increase with age if the work performed remains similar? It is 110t without
interest that the classes mentioned as having low repair costs are also those
of which fairly large numbers were built not long before the .dates relevant
to Table V. This would probably not affect the general conclusion but might
affect the degree of difference. Similarly, was it necessary to make any
allowance for the type of service performed by various classes? The Author
h~ referred to the fact that different conditions and methods of repair affected
the cost but does not say if any allowance was made in arriving ~t the repair
cost indices?
The writer's only personal experience of the engines reviewed was the erection
and running in of most of the second batch of Garratts in 1930. At the time
it seemed strange that they were built without inner carrying wheels, giving
very heavy loading of the rather undersized axle boxes and probably adding
to flange wear. Admittedly, the axleboxes were not so severely loaded by
piston forces as in the case of the inside cylinder 0-6-0 Class 4 engines.
The use of the short travel valve gear seemed then, as now, quite inexplicable,
especially in the second batch of engines.
It is very interesting that in ail those cases where test figures and long
period averages are given for coal per mile for passenger locomotives and
where the journey covered on test can be taken as closely representative
of the general duties the.. long period consumption IS almost exactly 4/3
times the test figure, i.e., 1.363, 1.360, 1.364, 1.356, 1.328 (almost too
consistent !), while other values 1.09, 1.495 and 1.462 are not strictly
comparable.
This increase is presumed to be due partly to the fact that the long-term
figure contains bad as well as good conditions, that the generality even
of top link drivers are not as skilful as the test drivers and that the tests
are carried out with carefully selected coal, as is necessary if the figures
are to mean anything. The consistency, however, gives authority to any forecast
based on the test results.
D.W. Peacock (155). Towards the end of his interesting
paper, the Author says that in some of the L.M.S. standard engines increased
efficiency has to be paid for by lack of " guts," or overload capacity, as
compared with the older types. While in some cases this may be so, it would
be interesting to have the Author's reasons why he considers efficiency must
necessarily penalise overload capacity. A comparison of boiler and cylinder
dimensions of standard and pre-grouping engines is given in the table below,
most of the data being taken from Table II of the paper. The last column
was headed "Boiler Demand Factor" and was computed as (cyl.
dia.)2 x stroke x boiler pressure/ total evaporative
heating surface (for a two-cyl. engine), and gives a simple comparison of
boiler and cylinder dimensions.
Royal Scot 1,518
5X 3-cylr 1,548
Class 2 4-4-0 1,459
2-6-4 Tank 1,722
Class 7 0-8-0 1,274
Class 5 2-6-0 (Hughes) 1,371
Class 4 0-6-0 1,572
L. & Y. Class 5 4-6-0 1,334
LNWR Prince of Wales 1,301
George V 1,322
G2 0-8-0 1,061
On the whole the standard engines have higher boiler demand factor in comparison
with equivalent older engines. This does not infer that the engines are
relatively over-cylindered, but is a necessary consequence of the habitual
early cut-off working, with lower mean effective pressures. lt follows that,
in comparison with the older engines, a standard engine needs larger cylinders
to do the same work.
Comparing a hypothetical modern and an older engine with the same boiler,
and working at the same evaporation rate, the modern engine, with its larger
cylinders, would be working at an earlier cut-off and lower back pressure,
consequently the blast arrangement would require to be more efficient than
that of the older engine. The same general principle is presumably true for
the two. groups' of engines, namely: standard (mostly long valve travel)
and pre-grouping (mostly short valve travel). If, therefore, a standard engine
steams satisfactory in normal working, it should be capable of equal or even
greater overload than an older engine, since overload capacity is mainly
a question of the boiler supplying the steam to cylinders, which are always
capable of using it.
lt is true that some performances made by pre-grouping engines in the past
(when in first-class condition) show remarkable power of overloading, of
which, incidentally, the same engines appear to be incapable to-day. Part
of the explanation of the Author's contention may perhaps be that the modern
engines are not asked to put up similar', plerformances when overloaded,
and for this l'eason (and others), many drivers are not often disposed to
get the utmost out of them. Certain special runs made shortly before the
war would seem to suggest that modern engines can put up remarkable records
when driven all out.
Discussion at Derby Meeting on 14 January 1946; J.C. Loach
(161-3) was highly critical of the LMS lack of a small smart
tank engine. The Stanier 2-6-2T still had an undersized boiler. He was also
critical of the bissel trucks in spite of Stanier having modified them with
bolster bearing pads and check springs. The 16ft 8in fixed wheelbase was
excessive and the overhang was appreciable: he suggested 14ft or 14ft 6in.
Cox replied that the wheelbase was an "old Spanish custom" at Derby, and
that in later designs this had been reduced..: D.W. Sanford
(163-4) made a contribution which O.S. Nock was apt to paraphrase:
"it had been very pleasant to hear the Author recall the very interesting
years that followed the formation of the L.M.S., particularly for those who
were there at the time. It seemed to him that the three English locomotive
centres had very different outlooks. At Derby the nice little engines were
made pets of. They were housed in nice clean sheds, and were very lightly
loaded. There must have been a Royal Society for the Prevention of Cruelty
to Engines in existence. At Horwich they had gone all scientific and talked
in "thous.", although apparently some of their work was to the nearest half-inch.
At Crewe they just didn't care so long as their engines could roar and rattle
along with a good paying load, which they usually did. As regard Horwich
contribution, he thought that mention should have been made of the very excellent
Dynamometer Car which was designed and constructed by the old L. &. Y.
That was far in advance of anything used in this country, ... Whilst it would.
appear that Crewe design was largely inspired by Heath Robmson, it must be
admitted that the Western Division of the L.M.S. took heavy loads: although
servicing facilities at sheds were poor.". Also commented upon the replacemrent
of Schmidt piston rings by narrow rings: on the Royal Scots where coal
consumption was reduced from 70lb/mile to 35lb/mile. A similar replacement
on the Claughton class reduced coal consumption to that attatined by the
Caprotti modified engines. Finally he noted that the advantages of long travel
valve gear had been described by Colburn and that Benjamin Connor had used
it on Caledonian locomotives in 1859.
Discussion at Newcastle Meeting on 27 February 1946
R.A. Smeddle (168-9) that the old North Eastern
Railway did not have comparable problems in terms of rivalry which the Midland
and LNWR shared as the other constituents of the LNER were much smaller!
He had seen the first Royal Scot on a visit to NBL and considered that it
was "a most impressive locomotive" and experience of Lentz oscillating cam
and rotary cam valve gears led him to believe that poppet valves caused less
problems than Walschaerts or Stephenson valve gears . J.J.
Lovatt (169) considered that a disadvantage of poppet valves was
the large cylinder clearance and that this led to eddy currents in the flow
of the exhaust steam.
Journal No. 191
Bond, R.C. (Paper No. 458)
Ten years' experience with the L.M.S. 4-6-2 non-condensing turbine
locomotive, No.6202. 182-230. Disc.: 231-65 + 10 folding plates. 4 illus.,
20 diagrs. (incl. 4 s.els.), 10 tables.
Ljungstrom non-condensing turbine 2-8-0 locomotive on the
Grangesberg-Oxelösund Railway: illustration and side elevation. The
turbines (one for forward, and another for reverse working) were the major
distinguishing feature and these in turn placed considerable demands upon
the lubricating system, and to some extent upon the boiler. A feed water
heater was fitted. There was a double blast pipe and chimney. It was soon
found that the degree of superheating needed to be increased. Roller bearings
were fitted. There are data on availability and a detailed record of repairs.
Table 2 compared coal and water consumption of the turbine locomotive with
Princess Royal Nos. 6212 and 6210 on London to Glasgow workings with a
dynamometer car:
Engine | 6212 | 6210 | 6202 | 6202 | 6202 |
Miles | 1608 | 1608 | 1608 | 1207 | 1608 |
Coal lbs/mile | 42.90 | 44.98 | 42.4 | 45.15 | 41.6 |
Coal lbs/dbhph | 3.22 | 2.977 | 2.97 | 2.855 | 2.78 |
Water gallons/mile | 36.1 | 37.26 | 34.2 | 34.96 | 37.1 |
Water lbs/dbhph | 26.90 | 24.67 | 24.00 | 22.11 | 24.80 |
Bond used these data to show that No. 6202 achieved a lower coal consumption of over 6% except in the case of one run by No. 6212. Data compared the hammer blow inflicted by three classes: Coronation at 72 mile/h 3.47 tons per rail (whole engine: .24); 5XP at 72 mile/h 8.31 tons per rail (whole engine: .61) and classs 5 at 64 mile/h 7.59 tons per rail (whole engine: 9.03) Data were presented which showed that coal consumption of the Royal Scot class increased by 8% over 28,000 miles of running due to wear in the valves and pistons. Hammer blow and wear in cylinders was eliminated in No. 6202.
Discussion: Sir William Stanier
(231-3). who opened the discussion, said he was wondering what had
happened to the London Passenger Transport Board. During the present President's
term of office there had been two outstanding papers on steam locomotive
practice, and the Institution had been very fortunate to get them. As one
who had had something to do with the substance of the present Paper, he would
like to say how very much he appreciated the good work which the Author had
done in collecting so much information of the greatest value . He felt that
that was long overdue, and he was sure that it would be received not only
by the Institution but by the locomotive world in general as of outstanding
value.
He would like to say something about the inception of the locomotive, because,
having been himself connected with it, he perhaps knew more about it than
the Author could know. The work which was done on the Grangesberg-Oxelosund
Railway in Sweden was brought to his notice by Dr. Guy, who was then with
Metropolitan- Vickers; he thought that he (Sir William Stanier) would be
interested in the results that the Ljungstrom people were claiming for their.
locomotive. Dr. Guy suggested that it might be worth while going to Sweden
to see it. After discussing the information which he had obtained with Sir
Harold Hartley, his Vice-President, it was agreed that he should go to Sweden
with Dr. Guy to see the engine and find out what they were doing. As a result
of that visit the L.M.S. Ralway, he thought very wisely and progressively,
felt justified in askIng for a scheme to be prepared so that they could consider
whether it was worth while to build a locomotive of the kind in question.
Dr. Guy and his staff at Metropolitan-Vickers worked admIrably with the team
at Derby, and as a result of that good work the turbine locomotive was built.
In the Paper reference was made to the boiler being changed for one with
a larger superheater. He thought that at this stage he ought to confess that,
having been brought up as a Great Western man, he thought, with his limited
experience, that the Great Western were right and everyone else was wrong.
and that a two-row superheater was all that was necessary for a locomotive.
He soon had grounds, however, for altering his opinion. One of the things
which he discovered was that the conventional Schmidt superheater, with its
relatively large diameter elements, never superheated the steam right through
the section of the tube; but with the smaller units to which he had been
accustomed, and which were 1-in , in diameter, proper heat transmission did
take place, so that tne steam was superheated right through the tube. That
was an advantage of the type of superheater to which he had been accustomed,
but it did not give a temperature as high as could be used on a reciprocating
engine, and certainly not as high as could be used on a turbine engine; and
so he turned to the larger superheater which was put on the turbine locomotive,
and, as the Author said, those superheaters were now standard on the "Coronation"
class. He had therefore learned a good deal from the work which was done
on the L.M.S. with regard to superheaters ..
One of the troubles with the turbine locomotive was due to the arrangement
of the control, which was in the position usually occupied by the reversing
screw. When rotated clockwise, the six valves for the forward turbine were
operated, and when rotated anti-clockwise the three valves for the reverse
turbine were operated. Interlocking mechanism prevented the reverse turbine
clutch from being engaged until the handle was in the neutral position. The
point was that the interlock must not be released until the engine had stopped.
Before the war they had under consideration a scheme by which when the wheel
was rotated anti-clockwise and came to the neutral position it would be locked
there until the engine stopped. and then, when it was moved back to open
the reverse turbine valves, it would automatically engage the clutch and
then open the valves. That would avoid the necessity for a man from the C.M.E.'s
department being on the engine all the time to see that the drivers did not
make a mistake and damage the gear.
It must be borne in mind that with the 8-hour day it was impossible for the
Motive Power department to do what they would wish to do and keep one or
even two sets of men for the engine. At one time, when the engine was stationed
at Liverpol, it was worked by twenty sets of' men in turn, and there was
little hope of an experimental engine being successful in those conditions
unless there was someone there to maintain continuity of practice. There
was another interesting fact about the engine which he did not think had
been quite appreciated. He believed that it was the only engine built for
this country with roller bearings for all the wheels. He had been interested
in reading the Paper to see what little trouble those roller bearings had
given. Mr. Cox had referred to that in a previous Paper. The Timken Company
had collaborated with the L.M.S. in fitting up the engine and certainly provided
bearings that were well up to their job.' The care which they took to keep
water and dirt out of the bearings had led to very satisfac tory results.
He had always felt that the engine had been very successful, especially having
regard to past experience with turbine locomotives. It was largely from the
information that the Americans were able to get from it, which he admitted
was rather limited, that they were encouraged to build the turbine locomotive
for the Pennsylvania Railroad.
Colonel H. Rudgard (233) said he
had had the engine to run for some time and would like to testify to the
comfort in riding on the engine when it was running at speed. It was so
pronounced that it did not feel that one was on a locomotive at all. With
regard to its performance in traffic at the present time, it could be said
definitely that with confidence it was put on trains and even special trains
that were required to give a good performance. The teething troubles seemed,
at the moment, to have been very successfully overcome.
They had had a certain amount of trouble with the firebox and the tubes,
and especially. the large tubes at the firebox tubeplate getting dirty. It
was necessary to stop the engine for a thorough tube cleaning more often
than would be necessary with an ordinary reciprocating engine of the same
type. That was something which had to be tackled and overcome if they were
to have the availability which he felt they would be able to obtain with
the turbine locomotive when it was fully developed. There was no doubt that
they were getting a very fine availability from the ordinary 4-6-2s. They
were attempting to get 100,000 miles a year out of them at the present time.
It might be a difficult task to develop the turbine locomotive in such a
way as to compare with that, but from his knowledge of what had transpired
and of the present performance of No. 6202 he felt that the possibilities
were great. It was a high standard, however, to have to attain.
In the old days, when the Beyer-Ljungstrom locomotive was working on the
L.M.S .. people were not as sympathetic as they were to-day. It was allowed
out on the main line only with special permission, and at the slightest sign
of trouble it was taken off again for fear it would interfere with the traffic.
A more liberal-minded attitude prevailed to-day and everything was done to
see that not too much was made of teething troubles.
E.S. Cox (233-5) said that amongst
the advantages of turbine propulsion for locomotives which were set out in
the Paper, high power output figured as the last item. That was probably
in order in this country, where under present-day conditions the maximum
output of a locomotive was very largely keyed to the capacity of the fireman.
But it was otherwise abroad, and particularly where the mechanical stoker
removed all limitations to the maximum power output of a locomotive. N; a
sidelight on that, it might be of interest to refer to the privilege which
he had had within the last two months of making a footplate run on the
Pennsylvania turbine engine, to which reference had already been made.
Before he referred to the actual run, he would like to say a few words about
the background to the American engine. First of all, it was designed to provide
more power. The cry in America to-day was for more and more power to meet
the traffic needs of. greater
T. Henry Turner (239) noted that the smoother traction would be
appreciated by the passengers; D.R. Carling (243-4) noted that there had been improvements in condensing mechanisms, the possibility
of using a geared reciprocating engine for travel in the reverse direction,
and possibly acting as a "booster" to assist in starting: he also refered
to S.R.M. Porter's B-E bogie. H.I.
Andrews (252) could not understand what was going on inside the turbine when
the locomotive was exerting tractive force at standstill: Bond replied to
this with the assistance of R.A. Struthers of Metropolitan-Vickers (pp. 255-6):
basically the energy is briefly converted to heat within the turbine.
H. Fowler (261) noted th reduction in hammer blow
and thus reduced track maintenance costs and the possible reduction of wear
on firebox plates due to the constant blast.
Manchester Meeting 2 May 1946
Chaired H.H. Saunders
J. Hadfield (257-8) said that
many attempts had been made to recover the energy in the toe of the Rankine
Cycle and the turbine offered many possibilities. In discarding the condenser
the design had been considerably simplified but the availability of the steam
locomotive was largely determined by the condition of the boiler due to the
use of con- taminated water. By the use of the air-cooled condenser not only
was it possible to increase the thermal efficiency, but it was also possible
to reduce the water consumption to about 5% of that required by the
non-condensing locomotive. The actual saving in overall cost of operation
due to that reduction was obviously of much greater importance than the increase
in thermal efficiency, since the time required for washing out the boiler
and carrying out repairs necessitated by the use of contaminated water could
easily cause the locomotive, to be out of service for about one eighth of
its life-time. The Ljungstrom turbine locomotive built by Beyer , Peacock
& Co. was fitted with an air-cooled condenser and this locomotive showed
economies in water consumption of 95% as compared with normal type locomotives
employed on similar duties. The Autho; had been frank enough to admit that
between the same limits of pressure and temperature; the non-condensing turbine
locomotive did not show any large economy when compared with a modern
reciprocating engine and said that for an appreciable improvement in thermal
gain it would be necessary to use temperatures and pressures well above the
maximum that would be practicable with a reciprocating engine. In this connection
it would appear that the design of the boiler would become the limiting factor
since there were qbvious limits to the steam temperature and pressure which
could be attained by the use of the orthodox type of Stephenson boiler.
In contemplating the possibilities of future developments, he asked the Author
whether he considered that the steam turbine locomotive would be able to
survive the competition now emerging in the shape of the gas turbine.
Tritton, Julian S. (First Sir Seymour Biscoe Tritton
Lecture)
Locomotive limitations. 283-323. 17 illus., 17 diagrs.
Presented at Institution of Mechanical Engineers on 10 April 1946.
Figure 7 shows the now well-known photograph of bogie Sentinel locomotive
for Colombia with Woolnough boiler in Belgium with distiguished guests, including
Gresley and Bulleid. Noted that locomotive had excellent ride and reached
56 mile/h. On p. 296 it was claimed that King class had exceeded maximum
dimensions for a narrow grate. On page 297 there is an extensive quotation
from Sir Alan Mount's Report of the Pacific Locomotive Committee in which
it was stated that high speed operation of heavy modern engines will cause
inestimable damage to unsuitable track. He then proceeded to examine flange
forces on the track examining work performed in France, Germany, America
and India. He then considered large articulated locomotives: the American
Mallet and the Beyer Garratt and high pressure and multi-cylinder designs,
notably the Schwartzkopf-Loeffler locomotive and the Swiss Locomotive Company's
4-6-4 of 1937 for the Chemin de Fer du Nord which employed Uniflow cylinders.
He followed this by describing relatively traditional electric, diesel electric
and gas turbine motove power. Figure 34 shows Sir Seymour B. Tritton in his
Stanley steam car in about 1906..
Journal No. 192
Kelway-Bamber, Herbert (Paper 459)
Coal and its Post-war carriage on British Railways. 332-7. Disc.: 337-47.
Presented at Institution of Mechanical Engineers on 1 May 1946 shortly
before his death on 5 June. Sir William Stanier chaired the meeting and
contributed to the discussion. The paper was highly critical about the way
in which coal was handled by British railways, both in terms of the low capacity
wagons used and the use of wagons as a form of low cost storage. Statistics
of coal conveyed:: criticism of failure to employ bogie wagons and the low
(9.5 tons) amount conveyed per wagon. Wagon productivity was extremely low:
on avaerage each wagon ran about 8 miles per day. Discharge was mainly manual.
Train resistance was very high. In India and South Africa productivity was
much better: bogie wagons were employed in South Africa with a capacity
of 45 tons. Duncan Bailey (339-42), a wagon builder, stated that he had presented
a paper to the Newcastle branch of the Institution in 1935 (presumably in
IMechE Library) which had advoacted the use of steel for wagon building.
The situation was worse than had been estimated: the 12 ton wagon really
had a capacity of only 11½ tons and that it was not until 1923, rather
than 1913, that this capacity was attained. He noted that some "shuttle traffic"
was handled in 40 ton wagons, notably ICI limestone between Buxton and Winnington
and the LMS coal traffic [to Stonebridge Park] The Samuel Commission had
recommended 20 ton wagons. Most of the time coal wagons were used as storage
space. F.W. Sinclair (343) noted vthat coal merchants handled about 10 tons
per day and that this dictated wagon size. Stanier (p. 345) claimed that
the 20 ton wagons used by the GWR in South Wales enjoyed a special environment
with special fscilities for discharge. He considered that 50 ton or 60 ton
wagons were needed to increase the tare/weight ratio: in such terms two 20
ton wagons were better than one 40 ton wagon. T. Henry Turner considered
that the British Coal Utilisation Research Association should be involved
in wagon design.
Smith, K.A. (Paper No. 460)
Stages in the development of a railway dynamometer car. 348-80. Disc.:
360-89.
Includes a brief analysis of the various types of dynamometer then
available. This is followed by a description of a new dyanamomter car constructed
for the New South Wales Railways.
Journal No. 193
Association of Special Libraries and Information BureauASLIB.
399
Institution became a Subscribing Member [KPJ involved in much Aslib
activity at a later date]
Whalley, F.S. (Presidential Address).
The work of their craft. 401-29. 28 illustrations., 8 diagrams., map.
Mainly an account of the "Liberation" type built for UNRRA: the United
Nations Relief & Rehabilitation Administration: the 8F and Riddles Austerity
(2-8-0 and 2-10-0) designs are also considered: there were similarities between
the Liberation and Austerity designs. The Liberation type had a wide firebox
as the Berne loading gauge is more generous. The tender was very similar
to that fitted to the Austerities but ran on two bogies. Amongst the many
illustrations there are two of locomotives in transit by road from the Vulcan
Foundry to Liverpool docks. The road trailer was capable of being steered
from the rear and ran on solid rubber tyres. There are further pictures of
the locomotives at the dockside and being loaded into the hold of a
ship...
Nightingale, W.A. and Kamlani, M.V. (Paper
No. 461)
The use of experimental data in fixing the proportions of locomotive boilers.
430-69. Disc.: 469-86. Bibliog. 36 diagrs.
Based on Indian conditions. Paper divided into: Evaporation, Combustion,
Draught and Absorption. pp. 443-6: ashpan losses at low firing rates lesser
proportion of total fuel consumed than at high firing rates.
C.W. Clarke (472) commented at length with particular
reference to Indian coals
Journal No. 194.
Eastwood, Frank. (Paper No. 462)
Workshop gadgets in railway shops. 491-577. Disc.: 577-88.
Broad gauge railways in the Argentine.
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