THE BRITISH OVERSEAS RAILWAYS HISTORICAL TRUST
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Journal of the Institution of Locomotive Engineers
Volume 16 (1926)
The IMechE virtual library is accessible (full papers, all diagrams, photographs, extensive tables, etc).via SAGE |
Journal No. 73 (January - February 1926)
Case, Robert C. (Paper No. 188)
Statistics and coal consumption. 4-37. Disc.: 38-41. 3 tables, 9 diagrs.
Presented Manchester on 27 February 1925 chaired by Haigh.
Statistical analysis of coal consumption in India at one depot with especially
favourable characteristics. Considerable attention was paid to the statistical
methods adopted. Factors included locomotive type and intended duties, and
whether superheated or saturated. Freight was worked by 0-6-0s, but passenger
traffic was worked by 4-4-0s. 4-4-2s and 4-6-0s. Suburban traffic was worked
mainly by 2-6-4Ts, but some was worked by 4-4-2Ts. According to this statistical
analysis there was no clear advantage to be gained from superheating on suburban
tank engines. In other work it was possible to analyse the cost advantage
of superheating. The effects of speed, locomotive weight weight, train load
and locomotive maintenance on coal consumption were identified. In the case
of goods (freight) engines superheating showed a clear advantage. Sopme
consideration was given to coal quality, rates of acceleration and draughting.
Discussion: F.W. Attock (38-9). was cautious in noting that
it was difficult to measdure coal consumption. He supported Case's observatiuons
on superheating locomotives used for suburban services and
cited Hookham's paper (Paper 126) . J.N.
Gresham (39-40) examined the modern locomotive chimney and liner (if any)
and found it insufficiently large in diameter to pass all the air necessary
for satisfactory combustion together with the exhaust steam. Should the blast
pipe become, or be set, slightly out of centre with the chimney, a very marked
drop in smokebox vacuum will result. To obviate this, one of the Swedish
railways made them integral in one piece. G. Brooks (40) the Author statet
that fuel represents about 50% of all running costs, excluding main shop
repairs, and therefore he could not understand why feed water heating had
never come into prominence in Britain, whereas in Germany most engines are
so fitted, as also in France.
Cochrane, J. (Paper No. 189)
Water: its occurrence on the Central Argentine Railway. 47-91. Disc.:
92-111.
Presented in Argentine on 17 April 1925 chaired by M.F. Ryan
Discussion: Louis Greaven (101-3, Darsie,. Anderson & Partners) noted
the conclusions from a committee appointed to report on boiler feed waters
in the USA which divided waters into:
Alkaline waters causing foaming and corrosion
Hard and incrusting waters
Soft and non-alltaline waters,
Kimberley, R.E. (Paper No. 190)
Notes on the organisation and working of a running department. 124-49. Disc.:
149-89.
Argentinian conditions. Fuel and staff (engine and shed) costs were
the two biggest factors: both could be in excess of 45% of total operating
costs. Water quality was frequently poor.
Reid, R.W. (Presidential Address)
Developments in coaching stock construction. 192-7. Disc.: 197-220; 277-94.
Mentioned the development of articulated rolling stock on LNER. Noted
that demand for greater comford had led to increase weight. Noted use of
steel in coach construction. Steam heating had added to the cost, and electric
lightin placed a greater load on the locomotive. Unusual address for amount
of discussion included. Kelway Bamber (198-9; 277-94) advocated bogie wagons
which would lead to a 28% reduction in dead weight. S. Symes (204-5) noted
the cost of carriage heating and commented on steam pressure employed; E.W.
Selby (295-6) described the Bury electric rolling stock.
Journal No. 74 (March-April 1926)
Haigh, J.H. (Paper No. 191)
Fractures of locomotive parts. 230-8. Disc.: 238-47. 4 illus.
Fractures caused by bending, torsion, shear and in tension are
illustrated. A high proportion of failures in parts subject to shock takes
place in the screwed portion, as in brake work and drawbars. Some spring
hanger bolts are so designed and fitted that they are subject to slight but
frequent bending stress, resulting in flaws commencing at the bottom of the
thread from the two oppositc sides extend until fracture take place.
The stripping of threads either on the bolt or in the nut was occasionally
a source of trouble.
Saunders, P.H. (Paper 192)
Principles and practice in the erecting shop. 248-67. Disc.:267-75; 662-74.
Presented in Leeds on 20 November 1925 chaired by Kidd
Frames; frame straightening and cylinder setting; bolting up; fittings. It
should be arranged that heavy fittings such as brakeshafts, sandboxes, slidebars,
etc., which come between the frames, should be placed into position before
the boiler, to save time; testing the boiler; adjusting the safety valves;
lowering boiler into place; horns, axleboxes; wheeling; motion work, valves
and valve setting (covered at length)..
Bartram, J.H. (Paper No. 193)
Locomotive frames (a comparison of types). 299-308. Disc.: 309-12. 7
diagrs.
Presented in Manchester on 4 December 1925 chaired by Kidd
Frame evolution. The first locomotive had no frame, the boiler
providing the attachment for the cylinders and wheels. Springs and brake
gear were unknown, but independent frames were soon introduced and springs
and brakes added. Built-up frames, of wood with wrought iron flitch plates,
thin plates riveted together, cast iron frames, welded bar frames, forged,
slab and double frames were used and gradually developed into the modern
frame. An early defect in the design of the locomotive was the rigid connection
of the frames to the smokebox and firebox, and it was also a common practice
to couple the drawbar to the rear of the firebox. This system proved a permanent
source of boiler trouble that was only remedied by making the frame
self-contained and resting the boiler upon it so that it could expand freely.
The slab plate frame, introduced by Beyer Peacock at an early stage in the
history of the locomotive, provides an example which may be described as
midway between later British and American practice. The frames were
of wrought iron, the hornblocks being forged solid with frame plates, thus
entirely avoiding trouble with loose bolts or rivets andgiving a solid
support to the axleboxes. American engineers adopted the bar frame which
had been introduced by Stephenson in 1825, and subsequently developed
Plate frames
advantages:
very rigid vertically.
certain amount of lateral elasticity; gives slightly on curves at
speed
strong buffer beams and attachments.
stays, gussets and brackets easily attached.
deep firebox and efficient ashpan.
large coupled wheels can bc used under firebox.
good support to firebox, well above the grate.
Disadvantages:
axlebox guides and spring brackets offset
large number of bolts and rivets liable to work loose
cylinder bolts have to resist large shearing force.
Firebox inaccessible below frame for washing out.
Large number of cross stays necessary.
Bar frame
advantages
solid backing to axlebox guides and cheap and easily renewable shoes.
simple disposition of springs and compensating gear
f'ew bolts and no rivets to work loose.
cylinders easily fixed.
firebox accessible for washing out.
few cross stays required.
sections can bc proportioned to meet the varying stresses in different parts
of the frame.
disdvantages
excessive lateral rigidity.
lack of vertical rigidity.
weak at front end at buffer beam and behind cylinders where bogics are used
boiler centre must be very high to allow of ample depth of firebox at
tubeplate
ashpan narrow and inefficicnt.
very heavy.
large coupled wheels cannot he used under the wide firebox.
Conclusion. the bar frame was particiularly adaptable to American conditions
of ample loading gauge and large fireboxes and grate area, while the plate
type was most suitable for British requirements, except for special designs
such as the engine units of the Garratt locomotive. Plate frames are the
best for side tank engines, but this type is rarely used in America. .Any
change from plate to bar frames, or vice versa, could not bc economically
carried out. It was rather remarkable that on those railways abroad where
British-built plate-framed locomotives had to compete. against American
bar-framed engines, the fuel consumption was always in favour of the plate
frame, which permits the use of a decp firebox and efficient ashpan.
Shields, T.H. (Paper No.194).
The steam locomotive and its future in relation to electric traction. 315-27.
Disc.: 327-52; 498-501.
Presented in London by author's brother on 18 December 1925 chaired
by W.A. Lelean
Includes illustration of Riekie valve gear. Considered there was a
need for a locomotive which would be acapable of running over steep gradients:
electric traction showed less variation. The boiler was good manager of steaming
capacity. A decrease in driving wheel diameter could assist: he postulated
that the diameter of the driving wheel in inches equated with the maximum
speed in mph. Argued for electric traction for short distances and that the
Sentinel was suitable for light traffic. An Appendix (p. 338-41) gave details
of test running with 4P compounds bewteen Glasgow Central and Carlisle. (also
s. el of locomotive). Discussion: J.W. Cross (328) noted that in Germany
the Knorr feedwater heater suffered from choked tubes. E.A. Phillipson (328)
considered that exhaust steam injectors reduced coal consumption slightly,
but increased maintenance cost. Cross (328) responded by noting that all
GWR locomotives were fitted with exhaust steam injectors and suffered no
problems. J. Clayton (329-31) observed that the
SR successfully employed.exhaust steam injectors and achieved a 3-4% reduction
in coal consumption. He argued that larger boilers were more efficient and
repair costs were lower. Questioned Shield's reference to smokebox superheaters:
all were then of the tube type, and dampers were no longer employed. He cited
the success of compounding combined with superheating on the MR/LMS. Clayton
favoured the condensation/displacement lubricator.E. Graham (331-2) noted
that live ssteam was used for feedwater heating in power stations as it kep
the boilers cleaner. Phillipson (332) noted that top feed
reduces scale formation. Sight feed lubricators needed constant watching,
whereas mecanical lubricators did not. Subsequently Phillipson (335-6) noted
the rapid deceleration achieved by the Westinghouse brake; furthermore, the
pump used less steam than the ejector. Phillipson (342-5) contributed more
in writing where he commented upon the Chingford intensive suburban service;
the advantage of multiple-cylinder designs, long water legs in the firebox,
the over-stated advantages of short tubes, Carnot's formula
The three chief objections to early cut-offs raised by the late cut-off
exponents, and the methods by which they may he surmounted are:
(1) Excessive cylinder condensation. May be minimised by adopting high piston
speeds; these are not detrimental, provided that care be exercised in the
design of the reciprocating parts, and alloy steels being employed, in order
to reduce weight.
(2) Excessive wire drawing. May be obviated by using long stroke piston valves
or preferably poppet valves, whereby back pressure is at the same time
reduced.
(3) Greater fluctuation in torque. While there is admittedly a greater
pressure-range per stroke, and a somewhat lower m.e.p., the effects on the
final turning moment 'diagram are largely neutralised by the use of three
or four cylinders.
Incidentally, the importance of the big end bearing pressure per unit area
is somewhat overrated; the problem resolves itself into one of finding more
suitable white metal mixtures. Considerable economies are of course effected
by res,tricting the maximum cut-off to 50-60 per cent.
The advantages of using poppet valves are to a large extent nullified when
used in conjunction with ordinary radial or link gears, the inherent faults
of which are still reproduced in the steam distribution. Some arrangement,
such as differential cams, giving infinite variation of all valve events,
provision being made for the cancellation of the effects, of the rise and
fall of the engine on the springs, is preferable.
'I'here are two methods of increasing the acceleration of existing engines
operating purely suburban services : Firstly, assuming that the adhesion
factor is sufficiently large to make it feasible, by increasing the area
of the pilot, or first port of the regulator. Secondly, by increasing the
lead of the valves. This latter method, however, is not an unmixed hlcssing,
and should the engine be requircd to run subsequently on other servces, involving
higher peak speeds choking would occur. .
Holcroft. H. (Paper No. 195)
Steam heating of trains 354-80. Disc.: 381-405.
Presented in London on 28 January 1926 chaired by Reid
Steam as a heating medium for trains possessed several advantages. In comparison
with a water circulation of equal heating effect its weight is negligible.
The piping and apparatus are likewise of lesser weight and size, and a unit
of steam carries a considerable amount of heat, due to the latent heat given
up in the condensation of steam into water.
Certain freight trains for the carriage of perishables were steam heated
including banana specials on the Great Western Railway. The vacuum-braked
covered vans were insulated and fitted with steam pipes: the train pipe,
instead of passing under the floor, was carried up to the ends, where the
bare pipe traversed the area under the roof before descending at the opposite
end. This arrangemcnt warmed the air enough to prevent damage to the fruit
by too low a temperature.
Temperature of steam varies with its pressure, but no great advantages are
secured by a high pressure, as the additional heating is small in comparison
With the latent heat available; also the pressure is limited by the strength
of the flexible hose connections and the need to safeguard.passengers and
operating staff. It had heen found by experience that a maximum of 50 or
60 psi was the highest desirablc. The warming. of trains, athough not
necessitating any additional labour cost at its source, was not acconiplishecl
without some extra work thrown upon the locomotive boiler. In the first place,
the weight ol the trains is increased by the apparatus carried, and which
during six or seven months of the year is not operated, just as 1ighting
equipment has to be carried in the daylight hours when out of use, its so
much dead haulage.
Discussion R.W. Reid (381-3).considered that what Holcroft advocated would
not cope with severe Scottish conditions. Refered to Plenum system and noted
that the Wolverton system was only applied to former LNWR rolling stock.
T. Barty (Wolverhampton 383-7) quoted an anecdote about frozen passengers
travelling on a Southampton train; also critical of Wolverhampton system.
E.D. Trask (394) made observations about the ground main systems employed
at London termini.
Journal No. 75 (May-July 1926)
Eborall, E.A.
Swiss railway electrification. 410-18. 6 illus.
This paper which did not receive a Paper number is an abstract: Traced
the development of the Swiss Railway system and indicated its importance
in international communications. Early electrifications, included that of
the Burgdort-Thun Railway, the experimental line between Seebach and Wettingen,
and, at a later date, the more comprehensive electrification of the Simplon
and Loetschberg lines. Factors having an important influence on the
electrificziion schemes of the Federal Government are the dependence of
Switzerland on external sources for its coal supply, and, on the other hand,
the abundance of water power.
Geer, H.E. (Paper No. 196)
Modern locomotive superheating. Part 1. 419-41. Disc.: 441-50.
Presented in Leeds on 22 January 1926 chaired by Kidd
Author worked for Superheater Co. In Great Britain in 1925 only 7000
superheated locomotives, out of a total stock of 24,500. This part is concerned
about demands placed upon piston valves and diagrams show Hughes' ball relief
valves (Fig. 5); J.G. Robinson's compression release rings (Fig. 6); Beames'
Trick ports (Fig. 7) and J.W.D. blast pipe valves (Fig. 9). Discussion H.
Broscombe (442-6) discussing carbonization in piston valves: Noted that NER
S3 4-6-0 No. 931 was fitted with patent rings supplied by ABC Coupler &
Engineering Co. and these were claimed to lower friction; also noted the
importance of running on the valve gear rather than on regulator to obviate
wire drawing. G.F. Horne (446-7) spoke about the Hughes 4-6-0 and superheated
0-6-0 designs; leakage from superheater tubes and that Hughes type piston
valves were fairly satisfactory, but after 20,000 miles it was necssary to
remove carbon.
Rowntree, E.D.H.
Pressed steel in railway rolling stock. 459-61.
Presented in Leeds on 19 February 1926 chaired by Kidd: paper did
not receive a Paper number
Thorrowgood, W.J. (Paper No. 197)
Signalling from a driver's point of view. 463-85. Disc.: 485-97. 18 illus.,
1 diagr.
Presented in London on 26 February 1926 chaired by H. Kelway
Bamber
Mainly three and four colour light signalling on the Southern Railway.
The principal advantages were:-
same aspect is displayed both day and night.
definite: no question of drooping arms when an aspect is exhibited
smaller size: they can be brought down to a position in a line with the drivers eyes
no moving mechanism: drivers always see the aspects only.
track is kept clear of signal wires.
economy in maintenance.
aspects are brilliantly displayed
no red or stop light has to be passed.
Noble, E.C. (Paper No. 198)
Ferry steamers and Garratt locomotives in use on the Entre Rios and North-Eastern
Argentine Railways. 503-24. Disc.: 524-32.
Read on 19 March, 1926 at Ibicuy
The case for a Garratt trial included:
its low internal resistance through its flexibility and its high pressure
form as against the compound form of the Mallet, the Garratt could develop
its full tractive effort, as conclusively proved in South African railways
and elsewhere. The Garratt engine in service in the works ol Vivian &
Sons at Swansea showed that a Garratt with a tractive effort of 24,600 lbs
hauled a 33%. heavier load than two saddle tank engines, with a combined
tractive effort of 25,600 lbs (See Rly Gaz. 13 January 1924.) A further
example given in the Railway Gazette 8 June 1923, noted that the Garratt
hauls a load which is a greater percentage increase over the load hauled
by the ordinary engines than its percentage increase of tractive cfiort is
over that of the ordinary engine.
Bell, A.M. (Paper No. 199)
Automatic mechanical couplers for railway rolling stock. 540-74. Disc.:
574-86.
Presented in London on 25 March 1926 chaired by R.W. Reid
Review. W.F. Pettigrew (577-8); G.M. Rickards (LNER 582) commented
upon LNER experience with automatic couplers with Pullman vestibules and
stated that passengers were not subject to shocks.
Grime, T. (Paper
No.200)
Steam locomotive performance (theoretical and actual). 588-618. Disc.: 619-52.
Presented in London on 29 April 1926 chaired by H. Kelway
Bamber
On the theoretical side included compounding, the Uniflow (called
Uniflaw in paper) cylinder system and an analysis of "Castle" tests. Discussion:
J. Clayton (620-1) states that Churchward was responsible for introducing
long travel valves to Britain. Dendy Marshall (623-4) advocated compounding;
H. Holcroft (627-30) considered the difficulty of compounding in Britain
due to restriction on cylinder size; advocated long lap valves rather than
long travel valves; high boiler pressures did not lead to higher temperatures.
J.W. Hobson (R&W Hawthorn, written commuinication 638-40) described work
on three-cylinder tank engines for Argentina.. John Riekie (640-2) made
observations on compounding. Very brief report in
Locomotive Mag., 1926,
32, 156 .
Journal No. 76 (August-October 1926)
Nigerian Railwaay: new 2-8-2 type freight engine. 658-61.
Illus., diagr. (s. & f. els.)
Five built by Vulcan Foundry under supervision of the Crown Agents
for the Colonies; designed to the requirements of T.B. Otway Ruthven, the
late Chief Mechanical Engineer, were notable for having. three cylinders
and a large boiler, although the rail gauge is only 3ft. 6in. The Belpaire
firebox was copper and had a combustion chamber. Two sets of Walschaerts
valve gear operated the outside piston valves, while the valve of the inside
cylinder was operated by rocking levers.
Warden, Henry (Paper No. 201)
Physical testing of iron and steel for commercial purposes. 675-94. Disc.:
694-700.
Presented in Glasgow on 18 February 1926 chaired by D.C.
Urie
Listed incorrectly on IMechE electronic database as "Urie" and Warden:
D.C. Urie chaired the meeting. Discussion: E.G. Copestake (LMS, St Rollox
Works, 694) considered that the cost of sample preparartion was justified
by the superior performance of the Izod impact test; R.A. Thom (695-6)
was critical of the implied assertion made within the paper that the Izod
impact test was only used for Government-based work as several railway companies
employed the test. D. Dobbie (LMS, Inverness, 698-9) claimed experience of
locomotive boiler repairs, extending over a good many years: most trouble
was experienced along the legs of the back and front boiler covering plates
surrounding the firebox (the steel plates of barrel and boiler wrapper plates,
but ignoring the copper firebox). These back and front plates in addition
to being blocked and flanged, had numerous, rivet holes bored, drifted and
riveted up to enable a good fit being made of the plates where the boiler
barrel joined the firebox outer plates. It was around these parts inside
and outside of water spaces that most fractures developed, which required
patching from time to time. During the life of a locomotive boiler, say,
35 years, it may have worn out two fireboxes, and considering the fluctuations
in temperature to which it had been subjected and the treatment it received
whilst in service, the participant queried whether the tests mentioned were
sufficient to cover steel plates working under such conditions. Engines regularly
washed out at running sheds developed distinct markings along the inside
of wrapper plates directly abomve the foundation rings near the mud plug
holes where the washer-out regularly plied his cleaning rod. These markings
could only be detected when the boiler came to workshops for a new firebox.
In an old boiler they were occasionally so pronounced that there was a real
difficulty in knowing how to deal with plates so affected. Boilers with higher
pressures would lead to the adoption of thicker boiler plates. Fortunately,
fractures and defects of this nature develop slowly until the warning leakage
is duly noted, so there is not much danger of boiler casualties arising.
Robertson, James A. (Paper No. 202)
Spark prevention devices on locomotives. 703-21. Disc. 722-6.
Presented in Santa Fe on 19 June 1926 chaired by
Mainly as applied in South America, but Fig. 3 shows a Caledonian
Railway spark arrester.
Description of an eight-coupled turbine locomotive (Ljungstrom system) for
the Argentine State Railways. 727-37. illus., diagrs.
Detailed description of turbine, its condensing system, and the feed
water arrangements, and its fan driven draughting arrangement.
Handley, J.J.
Report upon trials of Ljungstrom locomotive. 738-40.
Water economy was being sought and tests were conducted in an arid
region. The time occupied during the run on the first trial totalled 30 hrs.
40 mins., the actual running time being 23 hrs. 20 mins. The load hauled
equalled 741,304 ton kilometres, with a consumption of 7,700 litres of fuel
oil and 6,100 litres of water, which gives a consumption of 10.4 litres of
petroleum per 1,000 ton-kilometres. 7-10
In the second trial, which took place on June 13th over a distance of 739
kilometres, the total load hauled was 733,820 ton-kilometres in 38 hrs.,
with 21 hrs. 25 mins. actual running time. The consumption equalled 8,750
litres of petroleum and 7,000 litres of water, which corresponds to 11.9
litres of petroleum per 1,000 ton-kilometres..
Tritton, Sir Seymour B. Presidential Address.
743-59.
Precis from Locomotive Mag.,
1926, 32, 316. After commenting on the wonderful work done
bv the pioneer locomotive builders with most elernentarv and crude material,
Sir Seyrnour gave a word of advice to those intending to follow the profession
of locomotive engineering. He particularlv emphasised the necessity for students
to follow carefully the best methods of manufacture and also the behaviour
of details and material under test. He expressed his disappointment at so
many of the candidates for India and colonial appointments, who had passed
high qualifying examinations, being unable to describe intelligently how
such a thing as a locomotivc tyre was manufactured.
He also touched upon the question of heat treatment. showing the great importance
which it held in the manufacture of modern steel, and how want of, or improper,
heat treatment, might be the cause of failure of the very best steel being
used, and even become dangerous. He illustrated this point by alluding to
the method of manufacture of screw couplings, amongst other parts, and suggested
that a Paper on the properties of materials and their relation to locomotive
design would be of interest. Sir Seymour expressed the opinion that the British
railways might profitably utilise some of the time spent by apprentices in
the mechanical department, for inspection and test work, so that they might
be better qualified for responsible positions on colonial and foreign railwavs.
Without making any historical retrospect, the President said it was somewhat
difficult to bring forward a subject of fresh interest in connection with
locomotive and carriage and wagon work. It is often said that the steam
locomotive has reached its zenith, that it will before long be replaced most
probably by the electric locomotive, and engineers should concentrate their
energies on the latter. In countries where water power is abundant (such
as Switzerland) and coal and oil are dear, there is little doubt that the
steam locomotive will gradually die a natural death. During a recent visit
to Switzerland, as one who had all his life been connected with the steam
locomotive, he was rather startled to see a large and central railway station
without any signs of any steam propulsion whatever, whilst the "Orient" express
by which he was ahout to travel towards England, came in to the minute, hauled
by a magnificent electric locomotive. These are signs of the times. But in
spite of coal and other troubles it would appear in this country the
steam-propelled locomotive will be used for long distance express and goods
traffic for many years to come, and it would be interesting to enquire what
arc the chief causes which stand in the way of its still further
development.
A very important subject next engaged Sir Seymour's attention, namely the
loading gauge of railways, and some verv interesting notes were given on
the different composite gauges now being worked to in Great Britain and on
the American continent, with some comparisons made with the new outline adopted
for the 5 ft. 6 in. gauge in Injdia. The loading gauge restriction, although
a serious drawback to the development of larger and more powerful locomotives,
has perhaps brought out certain developments, because the designer, being
unable to get the cylinders of his locomotive within the space required,
has been driven to turn his attention more closelv to three and four-cylinder
engines. Although, no doubt, the permissible axle load has been the principal
factor in the development of the articulated engines, such as the Garratt,
the Mallet and other tvpes, the restriction of the loading gauge has no doubt
also affected the development of their design.
When called upon for advice for new rolling stock for the metre gauge railways
in Iraq, Sir Seymour, in discussing the matter with the General in authority,
asked as to the limits of the loading gauge prevailing, and was informed
that it was represented by "the sky above and all round you." A very satisfactory
condition.
Referring to the efforts made by the Ministry of Transport to secure some
improvement in the British load limits to permit of more liberal interchange
of rolling stock with the Continent, Sir Seymour said it was found that the
improvements required on the single route from Dover to London would incur
expense of such magnitude that it could not be proceeded with.
For war service on the continent vehicles built to the French dimensions
were adopted, as the capacity of the wagons was increased by 10 per cent.
over tbe British. As some 3,400 locomotives and 73,796 wagons were built,
the question of dimensions was of importance. Apart from the limitations
of load gauge the progress of the steam locomotive in this country appeared
to be somewhat handicapped by the type of boiler used. Much higher pressures.
were being experimented with in Germany and elsewhere. He pointed out that
developments were now being pressed forward for steam locomotives, in the
form of Poppet valves and much higher pressures, and that the Diesel engine
had passed the experimental stage, and the combined steam and internal-combustion
engine on the "Still" system was being developed, and that new methods of
transmitting the power generated in the engine to the road wheels were engaging
the attention of the engineers of to-day. He asked that members who had studied
these subjects from various points of view would contribute papers to the
Institution upon them.
At the conclusion of the address, a vote of thanks was proposed by C.N. Goodall
(R. Stephenson & Co.), who congratulated the new President in thinking
out a new line in his address, adding his testimony to the value of the
Insitituton. This was seconded by Major S. E. Williams, (Crown Agents for
the Colonies) who stated that the success of the Institution has been greatly
due to the zeal and ability of its Presidents. He had known Sir Seymour Tritton
for many years and had co-operated with him in railway matters concerned
with the Crown Colonies, and his advice had inevitably led to success.
H. N. Gresley, (L. & N.E. Ry.) touched upon several points in the address,
confirming the great value he had derived when a pupil by a term in the testing
and inspection department where he learnt not only about the strength of
materials but methods of-manufacture and stating that, following on a suggestion
by Sir Seymour Tritton, his pupils were given the opportunity of going through
those departments. Gresley also alluded to the loading gauge, pointing out
the British loading gauges took into account the lengths of the vehicles
and the "throw over" on a curve, and fixed structures are set back to allow
for this, but in the Continental loading gauge this was not so and great
care had to be taken on this account. He was a member of the comrnittee which
had to consider a possible increase in the loading gauge on British railways,
when the "Berne" gauge was considered, and he confirmed Sir Seymour's note
that the cost proved prohibitive. He concluded by saying that he was glad
to note that the President was of opinion that the steam locomotive was not
yet dead as regards this country, and although experiments were being made
in much higher pressures, in his opinion this alone would not affect economy
unless special consideration was given to improved steam
distribution.
J.D. Rogers (Baldwin Locomotive Works) (757): I am glad to have the opportunity of thanking our retiring President, Mr.
Reid, for the good work he has done, and also to express my appreciation
of Sir Seymour Trittons splendid Address and programme of papers which
he has suggested for the coming year. The trend of development in America
in locomotive design is well known here; most of the engineers I meet are
as conversant with railway affairs there as I am. Wc have been forced to
take advantage of our clearance and loading gauges sooner than you have.
The principal difficulty with us has been axle load limits, and after our
engineers met the position brought about by increased loads on bridges and
tracks, we were then limited by fixed structures.
The diagram that Sir Seymour Tritton has given us represents as nearly a
composite loading gauge as could be devised. The railway that he mentioned,
the Boston and Albany, is one of the early railways in America and located
in the east; bridges and tunnels were constructed without anticipation of
the size of the equipment that would be required (in the future). It is true
that a truck which will pass the gabarit shown will go anywhere
in the U.S.A., Canada or Mexico. As we move westward the loading gauge has
been gradually increased with the more recent construction west of the
Mississippi River, except in the Rocky Mountains, we have the same conditions
as obtained in Iraq, i.e., only the sky as a limit. Unfortunately,
on account of interchange of equipment, railways cannot take advantage of
these clearances in increasing the dimensions of their vehicles; however,
it is different with locomotives. On the Virginian Railway, where I xvas
for many years, our maximum moving limits werewidth 12ft., height 16ft.
7½ in. ; locomotives had these actual dimensions, most of our rolling
stock consisting of coal trucks 120 tons capacity on six-wheel bogies.
Sometimes these gabarits that have been devised are not as accurate as the
engineers say they are. We had an instance of this. I was taking delivery
of an engine, a large Mallet weighing 450 tons, and three railways were offering
to take it. We decided to accept one particular route. The engineers examined
the engine and a start was made with only a twelve miles per hour speed
restriction. At the first bridge (through girder) the fireman said he did
not think the engine would pass over this bridge. When we approached it I
stopped and measured with a straightedge, and found that the low pressure
cylinders lacked six inches of clearing the floor gussets. Of course we did
not go further, but put into a side track for a few days whilst the bridge
was altered to clear the 44in. cylinders. This is just a sidelight
on gabarits.
To facilitate maximum loading of equipmcnt and to allow particular railways
to take advantage of their loading gauges, we have established
gateways, because if we only loaded our trucks to, the gabarit shown
on the diagram, we should lose a great deal of revenue. In accepting ;my
unusual pieces of machinery or heavy 1oads these clearances have to be carefully
examined and route made accordingly; there are twenty-eight gateways in America,
located geographically .
I am sure there are others here who have something interesting to say. What
I would like to see is for more of the members of this Institution to go
over to America so that we might reciprocate some of the courtesy we receive
here.
Visit to Crewe Works, 22nd July, 1926. 760
Between thirty and forty members of the Manchester Centre paid a visit
to the LMS Locomotive Works, Crewe: parties were conducted round the works
by Mr. Beames, his assistant, Mr. Lemon, and others of the staff. Members
had an opportunity of seeing the new erecting shop, which was nearing completion.
Great interest was taken in a four-cylinder unit fitted with the Caprotti
valve gear on the tappet valve principle, in connection with which tests
were to be carried out.
Sedgfield, P. and Forrest F.W.A. (Paper No.
203)
Illumination of railway rolling stock by electricity. 850-78. Disc.:
878-91.
Methods available in the Argentine:
Storage batteries under each coach without dynamo.
Storage batteries to light various coaches in parallel, without dynamo.
Storage batteries with generator in the brake van to light the coaches forming the train in parallel, driven either direct from the axle or by oil or petrol engine.
Storage batteries under each coach with turbine-driven generator on the locomotive.
Turbine-driven generator on the locomotive without any storage batteries.
Storage batteries under each coach with generator slung on the bogie of the coach, making a complete lighting unit for each coach.
Same as above but with generator slung from the underframe of the coach.
Journal No. 77 (November-December 1926)
Shawcross, G.N. (Paper No. 204)
Locomotive built-up cranks. 892-905. Disc.: 905-18.
Paper presented in Manchester on 26 February 1926 chaired by W.
Rowland.
The stresses which reacted most unfavourably upon built-up cranks were
Stress caused by the bending moment due to the weight of the engine, causing
opening and shutting of the webs or breathing to occur during
every revolution which the crank makes. This breathing action will be a varying
quantity, according as the driving wheel is momentarily in a depression or
striking a peak.
Stress due to the twisting moment set up by slipping of wheels when engine
is negotiating a curve.
Stress due to thc bending moment produced by the rolling or oscillation of
the engine causing the flanges of the wheels to strike a rail, thereby imposing
a bending moment on the crank, proportional to the radius of the driving
wheel.
Robinson, C.H. (Paper No. 205)
Debatable features in the design of some locomotive details. 919-35. Disc.:
935-43; 1927, 17, 346-54. illus., 10 diagrs.
Paper presented in Glasgow on 28 October 1926 chaired by D.C.
Urie.
Considered pistons with bull rings, with and without tail rods and
tail rod guides. The one-piece piston and rod of nickel-chrome steel as fitted
to LNER 4-6-2 type engines is very light, and the reciprocating weights are
reduced to a minimum, but its original cost is very much higher than the
ordinary type of piston and rod due to expensive materials, extra machining
operations, heat treatment, etc. The box type piston, with centre of steel
casting with bull ring cast on, had been adopted as standard by the Indian
State Railways. The production costs are again higher than those for ordinary
types, due to machining the periphery of the steel centre to take the bull
ring, and the extra cost of casting on the ring. The vexed question is, are
tail rods and guides of any use?
The main features of plate and bar frames were compared. Plate were deep
and flexible laterally, whilst bar were shallow with lateral strength whilst
flexible in vertical plane. Staying plate frames is achieved by vertical
and horizontal castings or flanged plates, secured by bolts and rivets. Bar
frames relied mainly on boiler, to which they were connected by semi flexible
stays at various points They were stayed by forged bars horizontally. Mountings,
such as spring and brake carriers were attached by bolts or rivets to plate
frames and via pins with collars put through the bar frame and secured by
nuts. Spring gear was almost invariably under-hung on plate frames, whilst
was almost invariably overhead on bar frames.
Reversing shafts could be: solid forged from steel billet; built-up from
mild steel; smithed from Yorkshire iron, with levers welded on (by then
obsolete); and steel casting (the last only being used for brake shafts at
the time). Firebox foundation rings were forged from rectangular bars in
Britain. In North America steel castings were used. Figure 5 showed a complex
foundation ring manufactured from a mixture of cast and forged components.
Five different methods of manufacturing smokebox saddles were considered,
particularly in relation to differences in machining time.
Discussion: D.C. Urie chaired the meeting and opened the discussion
(935-6) the idea behind piston tail rods was that of a floating piston, but
experience had shown that the piston had the dual task of carrying not only
its own mass, but that of the tail rod as well.
R.A. Thom (936-7) stated that when Schmidt superheaters
had been introduced it had been mandated that tail rods were fitted. On the
GCR it was found that tail rods led to wear in the centre of the cylinder
barrels, and they were removed. A large number ol cast iron piston heads
fractured, and piston heads made of hammered iron were substituted, but after
a time showed signs of fracture, and as a result, cast steel piston heads
were tried. It was found that these scored the bottom of the cylinder barrels,
and mild steel piston heads were then fitted, with very satisfactory results.
Bronze bull rings fitted to the nickel-chromium piston heads on the LNER
I'acifics have proved very satisfactory. As regards the merits of bar frames
compared with steel frames, the Author had evidently overlooked that the
Great Central Railway had also imported twenty Baldwin locomotives. These
were fitted with, bar frames, and a grcat deal more trouble was experienced
with them than uith plate franics, as the bottom web of the bar frame adjoining
the horn plates tended to break. At that time, there was no electric or
oxy-acetylene appliances in use and the frame had to be taken down and welded
in the smithy, which was a very costly operation. These engines proved so
unsuitable for English requirements, that it was decided to scrap the lot
after they hnd been in service for fifteen years. He could not agree that
a built-up reversing shaft or brake shaft was not as reliable as a solid
forged shaft. Casehardening the eyes of reversing shafts, motion details
and brake shaltshad been displaced by bushing: it had been found that bushes
are much more satisfactory, and repairs can be dealt with more readily. Bronze
bushes were better than steel.
Irvine Kempt (LMS, 937-9) advocated the retention
of tail rods until they had been fully evaluated. He noted that the circular
bush could not be properly lubricated, and led to excessive wear. The cylindrical
casing which surrounded the tail rods practically became a pump blowing out
any lubricant to the bush. If the tail rod bushes are not kept properly adjusted,
the piston rests on the bottom of the cylindcr, and the additional weight
of the tail rod being carried made conditions worse. Experiencc with shrunk-on
levers on shafts was limited to old Caledonian Railivay tender brake shafts.
When they got loose thc shafts were sent to the smithy for the levers to
be shrunk on again, and new set screws and keys were fitted: a crude
method.
E.W. Selby (939-40) could not understand why many British railways
retained the horseshoe front tubeplate bearing on the cylinders, instead
of using a circular smokebox. With this latter type, resting on a saddle,
it was possible to fit one type of boiler onto several classes of engine.
The GWR had used the circular smokebox with saddle on all new and rebuilt
engines since 1908. It makes a better job, and simplifies manufacture, if
the top of the inside cylinders is machined to a simple rectangle forming
the base for a steel saddle: steel is less liable to fracture, and saves
complicated machining, An alternative was to have two very much smaller
steel castings to form the ends, and to use two bent plates to form the sides:
a simple, cheap and strong arrangement.
W. Williamson (LNER, Cowlairs, 940) stated that cast steel piston
heads, with cast iron rings supporting them in the cylinder, gave very good
results. Dismissed tail rods and argued for simplicity. The keys on reversing
shafts with levers shrunk on tended to become slack. A forged shaft was much
better than a built-up shaft.
A. Hallam (LMS, St. Rollox, 940) had not found piston tail rods to
be satisfactory. Shafts of the solid type were preferrred as considerable
trouble was experienced with built-up shafts due to the various components
hecoming loose.
In his reply (941) the Author noted that the North British Locomotive Company
were compelled during WW1 to manufacture built-up crank axles, and had received
no complaints of loose pins, due entirely to the great care taken in finding
the essential shrinkage allowances, and to the production of first class
pins and holes.
Bond, R.C. (Paper No. 206)
Braking of trains on electrically-operated railways. 945-57. Disc.: 957-80.
Paper presented in London on 28 October 1926 chaired by H. Kelway
Bamber.
In conclusion, the following summary of the subjects under consideration
is offered as a basis for discussion
Alcock, E.
Some boiler details. 981-1002.
Address by the Chairman of the Leeds Centre on 29 October 1926: advocated
Belpaire firebox on the basis that it was easier to stay; there is greater
water above the hottest part; a continuous thread on both plates, and the
base of the seatings is flat. Also commented upon water space stays; tube
arrangements and crown stays..
Kelway-Bamber, H. (Paper No.207)
Modern British railway express passenger engines. 1004-17. Disc.:1017-29.
Paper presented in London on 25 November 1926 chaired by C.N.
Goodall.
Examines the performance of a Castle class locomotive between London
and Plymouth; the comparative running of Castle and A1 classes between King's
Cross and Grantham, and the Lord Nelson class, T.S. Finlayson
(1027) contributed to the discusaion with some rather
sharp remarks which noted the importance of firebox volume and noted
that superheating increased the volume of the steam. He considered that
locomotive horsepower corresponded to 50 times the grate area and therefore
expected 2000 hp from the A1, 1650 from the Lord Nelson and a mere 1500 hp
from the Castle
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