Journal of the Institution of Locomotive
Engineers
Volume 39 (1949)
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Journal No. 207
Dymond, A.W.J. (Paper No. 482)
Forty years of automatic train control — the Great Western system. 3-32.
Disc.: 33-51.
Fourth Ordinary General Meeting of thc Session 1948-49 hcld at the
Institution ot Mechanical Engineers, London, on Wednesday, 15 December 1948
at 5.30 p.m, Mr K.J. Cook, occupying the chair/
Includes an extensive contribution by P. Lomas (pp 34-40 on the Hudd
system).
Author
Patrick, D. (Paper No. 483)
Some notes on American locomotive practice 1948. 54-86. Disc.: 86-111.
Sixth ordinary general meeting held at the Institution of Mechanical
Engineers, London, on Wednesday 16 February 1949 at 5.30 p.m., Lieut.- Colonel
Harold Rudgard, President, occupying the chair.
Firstly commented upon the American loading gauge: 16ft in height and 11ft
in width and rail loads of 28 tons per axle being almost universal, and 32
tons on some line. Train loads of 5000 tons were common place. Began with
the unorthodox types of steam locomotive: the T1 4-4-4-4 Duplex type constructed
at Altoona Works of the Pennsylvania Railroad, the 6-4-4-6 S1 and 4-4-6-4
Q2 Duplex type were also noted, although it was noted that further Duplex
locomotives were unlikely to be constructed due to the excessive length of
the coupled wheel base. The 6-8-6 direct-drive non-condensing locomotive
built by Baldwin for the Pennsylvania Railroad weighing 260 tons without
tender was also mentioned and illustrated. The Baldwin 4-8-0+4-8-4 Baldwin
non-condensing steam turbine electric for the Chesapeake & Ohio RR with
a grate area of 112ft2 and the potential to develop 6000 hp: it
had the advantage of the turbine could operate at a speed independent from
that of the locomotive. Attention then turned towards conventional steam
locomotives: the Niagara class 4-8-4 employed by the New York Central RR:
these two-cylinder locomotives had produced 6600 ihp on test at 85 mile/h.
The streamlined 4-6-4 for the Milwaukee RR were commended ffor their pleasing
appearance which did not sacrifice accessiblility.
On freight locomotives the four-wheeled trailing truck had become essential
to accommodate a firebox of adequate dimensions. Non-articulated types included
2-8-4, 4-8-4 and 2-10-4: Fig. 6 shows a Lima-Hamilton 2-10-4 for the. Chesapeake
& Ohio RR. The Mallet articulated locomotives were mainly non-compound.
Fig. 7 shows a Lima-Hamilton 2-6-6-6 operated by the Chesapeake & Ohio
RR. Fig. 8 illustrated an American Locomotive Company 4-8-8-4 for the Union
Pacific RR with 23½ x 32 in cylinders and a grate area of
150.3ft2
Cast steel bed frames with cyinders cast in were almost universal. Fig. 9
shows those fitted to a Niagara class. The bogie frames were also made from
cast steel..
The boiler design of the Duplex T1 class was examined more closely, although
many features were almost universal. Nicholson thermic syphons were used
in multiple to provide adequate circulation, to increase boiler output and
provide safety. The Security Circulator is illustrated in Fig. 12.. Table
grates had tended to replace rocking grates. Crown axleboxes, roller bearings,
box-pok wheels were almost universal. Walschaerts gear was popular, although
some locomotives employed Baker valve gear and Franklin poppet valves were
sometimes used. For the historian of the steam locomotive Patrick provided
a good overall perspective> He was probably less successful in assessing
the impact of the disel electric locomotive where the main design features
noted were the ability to work in multiple and the cast steel bogies. Electric
traction was restricted to the GG1 Pennsylvania RR 4-6-6-4 which could produce
4620 hp at the rail and the flexible transmission was commended. Brief mention
was made of gas turbines. Cox (87-8) was critical of the failure to mention
the repair cocts for diesel electric locomotives and noted the low thermal
efficieny of American steam locomotives: 6 or 7%.
H. Rudgard (86) opened the discussion noting
that during WW2 when iron ore had to be moved from Kettering to Scotland
two class 8 2-8-0 freight locomotives coupled together hauled a gross load
of 2850 tons
Journal No. 208.
Borgeaud, Gaston (Paper 484)
The latest development of the electric locomotive in Switzerland - its mechanics
and some problems. 121-224.
Fifth ordinary general meeting of the Session 1948-49 was held at
the Institution of Mechanical Engineers, London, on Wednesday 19 January
1949 at 5.30 p.m.: Lieut.-Col. Harold Rudgard, President, occupying the
chair.
Issue No. 209
Forsyth, I.C. (Paper No. 485)
Some developments in locomotive workshop practice, 1939-1948. 231-83. Disc.:
285-310. 58 diagrams.
Improvements introduced at Crewe Works including shot-blasting,
hydro-blasting, steel melting and casting, locomotive cylinder casting in
steel, cold sawing, drop stamping, pulverized fuel fired re-heating furnaces
in the forge, oxy-acetylene and electric arc welding, automatic continuous
welding, stud welding, frame welding, machine tools, finishing of big end
and coupling rod bushes and axlebox straps and work inspection.
Armand, Louis (Sir Seymour Biscoe Tritton Lecture)
The influence of the treatment of boiler waters on the maintenance and
utilisation of steam locomotives. 328-51.
Jarvis, R.G.
Dynamometer car run, Rugby-Manchester (London Road). 353-5.
Run behind Caprotti-fitted class 5 No. 4752 on Tuesday 10th May
1949.
Bollen, P.W.
Visit to Messrs. Beyer, Peacock & Co. Ltd. on Thursday 12th May 1949.
Brown, D.C.
Demonstration run with dynamometer car and mobile test units — Manchester
(Central) to Derby on Friday 13th May 1949. 361-5. diagr., table.
5XP class locomotive
Hirst, G.W.C. (Paper No. 486)
The detection of cracks and flaws in axles and crank pins by means of supersonic
waves. 367-79. Disc.: 379-85.
Presented in Sydney
Journal No. 211
Williams, W. Cyril
Address by the President. The changing scene: some reflections on overseas
railway progress and problems. 394-444.
York, R.S.
The early history, later application and development of superheating in
locomotive practice. 446-72.
Chairman's Address in New South Wales. Noted that his initial experience
with superheaters had been on the GNR in England.
Journal No. 212
Alcock, J.F. (Paper No. 487)
Locomotive limits and fits. 477-502. Disc.: 502-31. 11 diagrs.
Bibliography.
Sir William Stanier (505-8) noted that locomotive
manufacturers in the United Kingdom had now adopted a universal system which
he regarded to be of great importance. He noted that he had seen Lelean working
out the limits and fits for the Indian Government Railways. He also acknowledged
the work performed in this area at Horwich. He noted that earson, when on
the GWR had encountered troublle with fractures in carriage axles this was
due to moisture getting in where the axles were pressed into the wheel. The
LMS had trouble with crankpins. Stanier himself had been responsible for
the burnishing broach having seen it in the USA in 1927. He observed that
Collett had sought to introduce parallel crankpins and this had led to many
breakages. Also included an extract on press fits from a paper presented
by H.J. Shrader to ASME in 1948.
Compton, J.N. (Paper No. 488)
Introduction and development of the pacific type locomotive for the broad
gauge in India. 532-50. Disc.: 550-6.
XA,, XB, XC, experimental XP, WL of the North Western Railway and
WP classes.
Woollatt, J.S. (Paper No. 489)
A criticism of some aspects of locomotive design. 557-71. Disc.: 572-83.
7 illus., 2 diagrs.
Meeting in Derby at the Midland Hotel on Tuesday 11 January 1949 at
19.00: E.R. Durnford in Chair.
Graduate paper.Since enclosure also improves conditions for the bearings,
enclosure of a locomotive valve gear and motion has more advantages than
disadvantages.
Another aspect. of mechanical performance is that of the whole locomotive
as a vehicle on the track. A smooth riding locomotive will, since lesser
forces are imp1ied, wear much better than a locomotive which rides roughly.
The subject of locomotive riding is one which has always been shrouded in
mystery, and the complete inability of locomotive engineers to come to terms
with the problem is illustrated by th,e inconsistency of methods adopted
to assist the wheel flanges in their job of constraining the locomotive.
It was found originally that the provision of. a fairly shallow flange was
sufficient to keep the engine on the rails, a logical later development being
the provision of side-sprung guiding wheels to reduce the side load occurring
at the leading coupled wheel flanges. The loading of the side control springs
at the guiding wheels has always been decided quite arbitrarily, since the
value of the various side forces involved cannot be calculated on account
of the variables involved, and, furthermore, would be almost impossible to
determine experimentally. It has never been known, consequently, exactly
how near a locomotive wheel may approach to derailment in normal service,
and on certain designs, the arbitrary method of providing side control has
been insufficient since derailments have occurred for no obvious reasons.
The position has become so ludicrous that designers have avoided. certain
types of locomotives because they doubt their ability to design specimens
which will keep on the rails. Examples of this attitude are given by the
antipathy of Southern Railway engiqeers towards 2-6-4 tank engines, and the
antipathy of everybody since Stroudley towards express locomotives with no
guiding wheels at the front. It has to be admitted that the problem is bound
to defeat everybody but the theorists.
There are two notable sources af infarmation on this subject. Ubelacker,
in 1903, provided a fairly simple method of determining lateral forces on
wheel treads and flanges when a locomotive is rounding a curve, but unfortunately
the theary begs the questian by assuming that a locomotive rounds a curve
smoothly. In ather words, he assumes that the side forces existing do not
change their magnitude, whereas what actually happens is, of course, that
the locomotive at speed is always swaying from side to side on the track.
F.W. Carter, in two Papers written in 1928 and 1930 attempted to find the
cause of the oscillation of the locomative and developed a theory arising
from the nature of the contact between tyres and rails and also the effect
of the coned tread. He showed that if the guiding af a locomotive by
side-controlled carrying wheels is correctly designed, the locomotive would
have a tendency to. keep to the, rails even without any flanges on the wheels,
provided that the wheel treads are coned. The significance of this is that
a locomotive so designed would behave very much better on encountering
irregularities in the track than one not designed to follow Carter's conclusions.
There are many examples af the truth of these conclusions. For, example,
he lays down that pony trucks must have an initial side controlling force,
so that an ex-L.M.S. 2-6-2 or a Horwich designed 2-6-0 both of which ride
well conform to Carter's conclusions, while an ex-L.N.E.R. Class V2 2-6-2,
which has a bad reputation, has a type of side control which exerts no initial
control on the front or back end of the locomotive. A strong case can be
made out for the adoption of Carter's principles, but they appear to have
received no attention up to the present.
A slight contribution towards the aim of improving the riding and reducing
the derailing tendencies of locomotives concerns the bearing spring fitted.
A leaf-type wheel spring in new condition can, by virtue of the friction
between 'its leaves, vary the load it exerts from, 10 to 8 tons without changing
its deflection. When it ~s in old conclition the load can vary from 10 to
6 tons. Conversely, a wheel which carried 10 tons when weighed might eventually
continually vary its load on the rails between 10 and 14 tons.
This effect of continually varyirig wheel load will have a certain tendency
to cause a locomotive to roll, but it will not be a serious effect since
the friction in the springs will rapidly damp out any rolling. The most serious
result of this effect will be that anyone wheel may have a small vertical
load on it at the same time as it takes a large lateral load, so that the
derailing tendency at that wheel will be great. The reduction in wheel load
occurs since the damping effect of the friction in the springs is bi-directional.
If damping were provided in the upward direction only, the wheel loading
would be allowed to increase on any one wheel but not immediately to decrease.
This could be done by using coil springs in conjuction with a uni-directional
dashpot at each wheel.
There are other reasons why such an arrangement would be advantageous. It
appears that. the conditions of operation of locomotive wheel springs are
so arduous that it is impossible to design and manufacture cheaply a spring
which will give satisfaction for a long period. After a few months' service
a leaf spring acquires a set, presumably because the stresses involved are
much higher than anticipated. There is also the fact that no satisfactory
method has been evolved for preventing the leaves of a spring from moving
in the buckle. Coil springs are open to neither of these disadvantages and
are objectionable merely an account of their lacking any damping characteristics.
If, therefore, a damped coil spring suspension unit could be used, leaf
springs,could be entirely eliminated. The reduced cost of coil springs instead
of leaf spring suspension would partially compensate for the cost of a damping
unit.
A possible arrangement is shown in Fig. 3, and.would be applied to the coupled
axles only, carrying axle springs being undamped. The damping forces needed
could best be determined experimentally, and it is probable that on a medium
or slow-speed locomotive damping need only be employed on one axle. The
arrangement shown employs two coil springs in the conventional position,
with the load transmitted via a bridge to faces, in contact but unclamped,