Journal Institution of Locomotive
Volume 9 (1919)
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Journal No. 37
Kidd, J.W. (Paper No. 67)
Firebox stays. 2-51.
Discussion meeting at Leeds, 26 November 1918
All locomotive engineers will agree that the most important feature of a locomotive is its boiler. Not only does the successful operation of a locomotive largely depend upon its boiler, but the general cost of maintenance of the engine is very much affected by the amount of repairs the boiler may from time to time require. As a contractor, who has been responsible for the building of many locomoti\es, I have been very much struck by the different specifications and drawings one is asked to work to, and the great difference of opinion one finds amongst locomotive engineers about the design of locomotive details, and this is my apology, if such be needed, for asking members to discuss the relative merits and demerits of different methods in common use of staying locomotive fireboxes.
Mercer, I.E. (Paper No. 68)
The training of the locomotive engineer. 55-69. Disc.: 70-106.
Seventh Ordinary General Meeting of the 1918 Session was held at Caxton Hall, Westminster, on 21 December 1918, at 2.30 pm., Mr. H. Kelway-Bamber, M.V.O., Member of Council, presiding: then President-Elect Ryan for Paper
As at Crewe where pupils were directly under the control of the Chief Mechanical Engineer whilst premium apprentices served under the Works Manager: most pupils started their apprenticeship as premium apprentices at Crewe.
Ryan, M.F. [Paper No. 69]
Presidential address. 122-33.
Some of the problems encountered during State control of railways during WW1. It is commonly believed that America and Germany learned the advantages of mass production on the interchangeable system from the experience gained in the manufacture of munitions, the former in the Civil War and the latter in the Franco-Prussian War. Let us hope that our war experience will teach a similar lesson. He then considered tolerances and gauges.
Journal No. 38 (February 1919)
Thompson, T. (Paper No. 70)
Locomotive building practice. 139-52; 175-89. Disc.: 155-74.
First Ordinary General Meeting (1919 Session) of the Leeds Centre held at the Philosophical Hal1, Leeds, on 28 January, 1919, at 7.0 p.m., Colonel E. Kitson Clark, Vice-chairman, presiding.
Based on NER practice at Darlington: boiler construction, flanging of plates, machining and trimming, assembling, the firebox, boiler mountings, tubing, testing, forge and smithy, springs. E. Kitson Clark (155) was critical of the failure to adopt standard boiler stay sizes. H. Holcroft (155-7) was critical of the method adopted for copper plate flanging and considered that hydraulic pressing should be adopted.He also advocvated American methods for the fitting of boiler mountings. W.A. Lelean (159-61) was surprised that no caulking was permitted for the boiler mountings. R.P.C. Sanderson (Baldwin Locomotive Works, 162-3) was critical of the hand flanging methods followed at Darlington. W.J. Bennett (LBSCR, 163-7) described the adoption of hydraulic flanging at Brighton Works since 1906.
First Ordinary ,General Meeting (1919S ession) was held at Caxton Hall, Westminster, on 20 February, 1919, at 7.0 p.m., Mr. M. F. Ryan, C.B.E., President, presiding.
The formal business having been concluded, the paper read by 3fr. T. Thompson on " Locomoti\e Building Practice " at Leeds on 28th January, 1919, was read by the General Secretary, 'on behalf of the Author, who was unable to be present. The Paper was illustrated by over 50 lantern slides, specially made for the reading of the paper at Leeds and London...
Bazin, J.R. (Paper No. 71)
Suggestions for standardized wagon designs for British railways. 191-206. Disc.: 206-40.
Second Ordinary General Meeting (1919 Session) of the Leeds Centre held at the Philosophical Hall, Leeds, on 25 February, 1919, at 7.0 p.m., H.N. Gresley, Chairman of the Leeds Centre, presiding. Due to illness of Bazin paper was presented by A.T. Houldcroft.
Paper noted the strategic importance of standardisation: "from a military point of view standardisation is of the utmost importance". Proposed 12-ton open wagons with high, medium and low sides; a 12-ton covered wagon, and a 20-ton open wagon for coal. All the 12-ton wagons could share the same wheels and underframe. Discussed steel versus wooden construction and opted for the latter due to its longer life. Buffing, drawgear, wheels, axles, axleboxes, bearing springs, brakes and bodywork were all examined. A table listed the dimensions of wagons within the capacities specified on all of the main line railways. Gresley (207-8) was highly supportivae of standardisation for wagons "whatever may be said about locomotives"!, but he considered that the registered carrying capacity was too high as the average existing loads were very low. Gresley was highly critical of private owners' wagoons. J.W. Dow (NER, 208-11) agreed that "it will be a long time before we give up building wooden wagons, especially coal wagons." The experimental use of steel wagons for coal had not be satisfactory. He doubted if the low-sided open wagon was needed, noted that the high-sided 12-ton wagon was virtually a stndard NER type, and the continuing need for wagons to handle specialized freight. G.N. Kitchen (NER, 211-12) tended to find reasons for not standardising wagons citing the needs of special traffic: sleepers, cotton bales and pig iron, but did agree that average loads tended to be low. Duncan Bailey (212-15) would like to have known what the Great Western Railway's exerience had been with steel wagons. Also noted that most plants and the bulk of the workforce could handle timber construction, but that Britain was not self-sufficient in timber.Gave statistics (1902) for the capital cost and earning capcity for private owner wagons and estimated a return of about 10% per annum.
Journal No. 39
Groom, S.W. (Paper No. 72)
Tube failures. 249-52. Disc.: 252-4.
Meeting at Leeds on 25 March 1919. Classified as leaking tubes, broken and pitted tubes and collapsed tubes. Based on experience at Doncaster Works..
Discussion: W. Paterson (L. & Y. Rly., Low Moor) : It seems to me an expensive luxury to bead the tube ends. the practice of expanding and ferruling them is more satisfactory. To prevent the tube ends being burned away, you may remember a type of ferrule being put on the market some years ago, having its outer end turned over so that when the ferrule was in position the tube end was completely covered and protected. That appeared to be quite a successful compromise between the practice of beading the tube ends and the ordinary practice of expanding and ferruling them. With the latter practice we get excellent results both with new and pieced tubes. In connection with the leakage of new steel tubes, I should like to ask Mr. Groom if he does not think that the thickness and shape of the tubeplate has much to do with the trouble. Was his experience of troublesome leakages confined to one type of tubeplate? We do not find new steel tubes particularly troublesome.
Mitchinson. H.W. (Paper No. 72a)
Broken crank pins. 255. Disc.: 255-8.
Meeting at Leeds on 25 March 1919. This paper refers to an 0-6-0 with 4ft coupled wheels and an 0-6-2T with 3ft 9in coupled wheels and traffic betwen Lofthouse, Robin Hood and Stourton, so presumably Mitchinson was in charge of the locomotives on the East & West Yorkshire Union Railway. Cited Brymbo Steel as being of superior quality.
Hamers, J.P. (Paper No. 72b)
Overheated bearings. 259-67. Disc.: 267-73.
Meeting at Leeds on 25 March 1919. Also includes fractured axleboxes.
(a) Overloading in a vertical direction.
(b) Overloading in a horizontal direction.
(c) Uneven distribution of lubricant.
(d) Presence of foreign matter and water
Gass, E.M. (Paper No. 73)
The relation of cylinder and boiler power to locomotive rating. 276-338. Disc.: 505-13; 514-17: 1920, 10, 315-19.
The Paper is divided under two headings:
ENGINE POWER: the power the locomotive is capable of exerting behind the drawbar, and the loads it can haul at various speeds on a straight track and on various grades and curves.
BOILER POWER the capacity of the boiler to meet the demands upon it, so that the engine can economically haul its loads at given speeds on various grades.
The deductions were made on experiments carried out on the Lancashire and Yorkshire Railway with goods trains composed of wagon stock of 10½ tons gross weight each (wagon plus load), hauled by locomotives (0-6-0 and 0-8-0 types) using saturated and not superheated steam.
Lawford H. Fry (505-13) commented on this paper and Gass responded pp. 514-17.: Brewer responded to this (10 315)
The Fourth Ordinary General Meeting (1919 Session) of the Leeds Centre of the Institution was held at the Philosophical Hall, Leeds, on 27th kfay, 1919, at 7.0 p m . , Mr. J. \V. Kidd, Member of Committee, presiding. The Minutes of the meeting held on 25th March were read and confirmed. MIr. H. N. Gresley (Chairman of the Leeds Centre) and Colonel E. Kitson Clarke wrote regretting their inability to be present. Mr. A. T. Houldcroft, the Hon. Secretary, was prevented by illness from attending. The formal business having been concluded, the Paper by Mr. E. XI. (;ass on " The Relation of Cylinder and Boiler Power to Locomotive Rating " was discussed
J. Weatherburn (N.E. Rly., Darlington 347 et seq): showed a diagram which illustrated dynamometer tests of one of the North Eastern Railway class T2 superheated mineral engines, which has practically the same diameter of wheels and cylinders and the same length of stroke as the Lancashire and Yorkshire engine 0-8-0. This diagram (Fig. 12) shows a maximum power test, with a cut-off of 73 per cent. of the stroke, and the regulator full open, the boiler pressure being 180 and the temperature of the superheated steam 600°F. The diameter of the driving wheels is 4ft. 65/8in. and the cylinders are 201/8in. dia. with a 26in. stroke.
The maximum starting pull on a gradient of 1 in 103 was 12.72 tons after correcting for gravity and acceleration on engine, which is equivalent to a mean pressure of 148 psi on the pistons.
The starting pull was made under the most favourable conditions, the engine only stood one minute before starting so that the cylinders would be very hot.
The equation to the speed and pull curve is Y=13.10.225 X (Y=pull in tons, x=speed in miles per hour), and the equation to the horse-power curve is X x Y/0.1675 or approximately 6 x X x Y . To the various engine resistances mentioned by the Author I should add the resistance due to passage of steam through the blast pipe, which is nil at the start, but it may absorb as much as 70 horse-power when the piston speed is about 1,300 feet per minute.
With regard to train resistance, a glance at Fig. 3, which shows curves of train resistance (which are constructed from different formulae for 10½ ton wagons) leaves very little hope for agreement on this section of the Paper, especially so when the Author prefers another mans train resistance curve to his own.
Wind and atmospheric temperature make a wide difference; a gale of wind has been known to increase the train resistance by 60 per cent.
A good introduction to the study of this subject is to watch single wagons running down the hump of a shunting yard, and note the various speeds they acquire; in cold weather some have to be pushed down.
Referring to the Lawford Fry curve and to the starting pull for a load of 703 tons, on a gradient of 1 in 103, by using the starting resistance shown on the above curve, the total resistance due to gradient and train resistance would be 13.35 tons, but the train resistance plus resistance due to gradient is 11.2 tons, so that if the resistance curve had been relied upon for fixing the load on this gradient, a much less load would have been hauled. The actual starting train resistance works out at 14.2lbs. per ton and this includes resistance due to acceleration.
Another dynamometer test. over the same piece of road shows that a steady pull of 11.4 tons maintained a speed of 19 miles per hour with 800 tons of empty wagons behind the engine; this pull gives a train resistance of 10.35 lbs. per ton, which agrees with the Lancashire and Yorkshire tests, while the Lawford Fry curve shows a resistance of 14lbs. per ton at this speed.
It often occurs that the maximum load is determined by the weight that an engine can stop in a given distance. The two determining factors involved are the weight of the engine and its brake power. This gives another ad\antage due to a large boiler in addition to that of being able to produce more steam.
The maximum load which the engine can haul on different gradients at different speeds can dasily be determined from the pull and speed curve. For example, what is the maximum load that can be hauled at a speed of 15 miles per hour on gradients of 1 in 100, 1 in 150, and 1 in 200, when the train resistance per ton of load is that shown by the Lawford Fry curve, Fig. 3; at 15 miles per hour the maximum D.P. pull on the level is 9.7 tons.
Journal No. 40
Dewhurst, P.C. (Paper No. 72)
Steel fireboxes and tubes in locomotive boilers. their service, maintenance and repair. 365-98. Disc.: 399-438. 34 diagrs.
The Second Ordinary General Meeting (1919 Session) was held at Caxton Hall, Westminster, on 1April, 1919, at 2.30 p.m., Mr. B. K. Field, Member of Council, Brighton, presiding. The ordinary business having been concluded, a Paper by Mr. P. C. Dewhurst, Loco. Supt., Jamaica Government Railways, on " Steel Fireboxes and Tubes-their Service, Maintenance, and Repair " was read by the General Secretary on behalf of the Author.
Based on experience gained on Jamaican Railways. Steel fireboxes were introduced onto this rail\vay in 1890 on .American type and American built locomotives. The first steel replacement firebox to he fitted to an English built and type of boiler was applied in 1903, and all whole firebox replacements for such boilers have since been made in steel. The first English boiler built with a steel firebox was placed in service in 1910, following which no new copper fireboxes were put in.
The parts which need careful watching with steel fireboxes are :-
Stays, as if broken this may not be observable from a bulge in the sheet, as steel plates naturally will not bulge as readily as copper.
2. Cracks in the plates, which should be very carefully looked for. and for this purpose the boiler should have water in it. This also enables the examiner to see whether-
3. Patches, if any, or cracks through the laps of flanges (if any exist), are leaking or not; all leaks in the firebox show worse when the boiler is cold.
4. Thinness of sheets where wasted, which is, of course, preferably tried by hammer test when there is no water.
5. Beads of tubes, which should be closely inspected to detect any signs of movement in the tubehole and to note the amount of bead burnt away.
With regard to broken stays, the following defects necessitate stopping a boiler from service for repair
Two or more adjacent broken or plugged stays in any part of the firebox
Three or more broken or plugged stays in a circle 4ft. in diameter
Five or more stays broken in the entire firebox.
Hydraulic and steam tests and general boiler every three years.
Discussion: B.K. Field (399-402) noted that Stroudley D1 class had been fitted with steel fireboxes. There were problems with cracking and with welding. Steel patches had been used on the Vulcan C2 class 0-6-0s, but he remained in favour of using copper. Smith Mannering (LBSCR, 403-5) also made observations on the use of steel patches in copper fireboxes. J. Clayton (405-8) considered copper to be best. The maintenance of steel fireboxes is a much more serious concern and repairs were difficult to execute. Low Moor rivets are best for inside firebox work. B.K. Field (416-17) commented on the staying of fireboxes noting that the GWR did not experience problems with tubeplates due to their liberal proportions, but on the South Eastern Railway during the 1887-1908 period tubeplate cracking predominated.
Sanderson, R.P.C. (Paper No. 74)
Notes on recent American locomotive and wagon practice. 443-9. Disc.: 449-54.
J. Clayton (450-2) stated that he was "horrified" by the use of cast iron wagon wheels in the USA. He was also interested in the use of powdered coal, Duplex stokers and the use of bronze valves and piston rings on the Union Pacific Railroad to combat problems when coasting for long distances downhill.
Journal No. 41
Rowland, W. (Paper No. 75)
An approximate method of estimating superheat and boiler output and evapourative efficiency. 459-69. Disc.: 470-504.
Third Ordinary General Meeting (1919 Session) held at Caxton Hall, Westminster, at 19.00., 29 October, 1919: Mr. B K. Field, Member of Council, Brighton, presiding. Based on Great Central Railway experience.
Although an enormous amount of literature on the subject of locomotive superheaters has been published during recent years, much of it has been merely descriptive of particular structural variations of the same essential device, and the remainder has largely consisted of records of the performance of engines fitted with one or other of the aforesaid arrangements as compared with others not so favoured. As to the general question, to superheat or not to superheat, there can at this stage be no doubt as to the answer, though even yet there are still one or two writers who appear to dissent from the obvious. With this phase of the subject the writer does not propose to deal, regarding the day for missionary work in this connection as past. It is no longer a question when designing a new engine, shall it have a superheater or not, but at what temperature of superheat shall it work.
Neither does the Author propose to deal with the relative merits of the various superheaters in use to-day, since their respective originators may safely be left to point out their advantages in the way of low first cost, low maintenance charges, freedom from liability to failure, and SO on. The purpose oi the 1apc.r is not to compare the rival arrangements and endeavour to hold the scales of justice fairly as regards their varying claims, neither is it to deal with the fuel economy and other blessings that the superheater can and certainly does confer, and the means by which it attains them. This side of the question has been and is still being ably handled, from the thermo-dynamic point of view, by others far better qualified than the Author. There is, however, one side of the subject upon which singularly little information has been published, and that is the design of a superheater to produce a given working temperature, and its converse, the working temperature that any particular design of superheater may reasonably be expected to give, together with the weight of steam at that temperature that the boiler in question will deliver per pound of fuel. Little or no guidance on this subject has been published, to the Authors knowledge, with the possible exception of Herr Garbes paper. The Author has therefore been driven to evolve for himself a method by means of which a solution of tbese conundrums may be attempted, and after hunting many false trails has arrived at a process which has so far given results in close agreement with actual observation over a very wide range of smoke-tube superheater designs for both locomotive and tubular marine boilers.
Discussion: The Chairman: (B.K. Field): had to apologise for the absence of the Speaker. Field was disappointed, after having read through the figures, as he was expecting to find at the end that there would be some short formula summarising the whole, but instead of that you get at the end the information that the Author is sorry that up to the present he has not been able to see his way to give us a short cut. In the early days when on the Brighton railway we were in course of adopting superheating, the first engine fitted as a superheater-No. 22-had 21 large smoke tubes 11ft. 2in. x 4¾in. diameter. There was a double return element in each, 21 elements, the outside diameter of which was, I believe, 13/8in. Well, the series that were built after that were all exactly alike except that they varied slightly in thc. diameter of the small ordinary flue tubes, 15/8in., 1¾in., 17/8in., although the diameter in the firebox tubeplate was the same in each case, the tubes being reduced at the firebox end to give the increased diameter in the barrel. When we came to Abergavenny 4-6-2T engine-we thought our experience in this direction was good enough to give us the same result in that engine with the same figures, and accordingly we designed her with 4¾in. tubes, 15ft. 8in. long; and she had, moreover, a bigger firebox than No. 22, and larger ordinary smoke tubes, these being 2¼in. The result was rather startling, as it was only when working very hard with heavy trains that we ever got anything much over 500°F. A little consideration of the various areas through the different tubes in comparison with No. 22 (which had less heating surface in the firebox and less grate area) showed that the later engine had too large a proportion in the small tubes, and that the gases from the flame in the firebox were going through the small tubes, and the big tubes were not getting their fair share; so we set to work to get out the relative cross-sectionar areas of the small and large tubes, and found it necessary to give Abergavenny a better proportion5½in. tubes (outside diameter). This was accordingly done, the tubeplates were reamered out for the larger size, and these big tubes put in, with the immediate result that we got the same amount of superheat, over 600°F, even when working moderately fast express trains, a result very much on all fours with No. 22, having the shorter tubes ahd rather smaller firebox. It appears therefore that we had discovered something which was of value to us from the experimental point of view, but we very nearly fell into a trap again when we built the first of the series of superheat Atlantic engines. These were originally designed to have the same diameter of tube and number of elements as Abergavenny (the 4-6-2T engine), but, at the last moment, on going through the figures, we discovered that the larger firebox surface and larger small tube area, and especially the larger grate surface, in the Atlantics demanded, not only larger tubes, but a larger number of them, and we accordingly put in there 24 tubes of the same diameter as Abergavenny, these also being 16ft. 3in. long. Those engines also have been very successful in the way of getting a high degree of supcrheat.
The propcrties of superheated steam have, I believe, been assimilated by most people in their early association with it, and perhaps one of the most interesting things about it is what one might call its dog in the mangerish property of keeping its heat to itself. One of its great advantages is that it does not part with its heat through the walls of the cylinder to nearly the same extent as saturated steam, but this also leads to a disadvantage which one is often surprised to find is unknown-it does not impart its heat to saturated steam when in association with it ; and this gives rise to the very curious thing that engines very often run with a high degree of superheat, but if the priming begins at all, the water of priming will go right through the superheat and appear at the chimney top before you know where you are. I remember on No. 22 engine particularly, when running on her first trials, we had been going on most satisfactorily and had, I think, 660°F. at the time, and I was watching the pyrometer hoping to see it go higher still, when I was astonished to see it suddenly falling rapidly. Like lightning all the possibilities flashed through my head, and it occurred to me that what was happening was that water was coming over from the boiler, was running past the bulb of the pyrometer, and greatly lowering the temperature, and I told the driver to shut off just in time to save the cylinder ends from being knocked out. He said to me : I thought it was impossible -the steam would dry up every bit of water that came through with it.
This Paper of Mr. Rowlands is aiming at quite a different thing altogether. He is really aiming at our being able to design any kind of locomotive of any size and get the desired amount of superheat from the proportions and lines on which it is proposed to build the boiler ; and that, of course, while it seems simple enough when we have three or four well-known typessuch engines as English practice usually represents, one could be almost copied with practical certainty when getting out another typeyet, when we come to such engines as are built in American and Continental practice, the size of which is extending so rapidly owing to the practically limitless loading gauge they have, it is very important indeed. I will not say anything mure at the moment, because I do nut know exactly what lines the discussion will take. We shall be very much interested to hear if any members have anything to criticise in the Paper or additions of an interesting nature to make to what is generally known about superheated steam.