DPW-DG70a

Aus der Dieselgeschichten-Sammlung der Dieselpensionierten Winterthur

Sulzer on British Railways (Part 1)

written by Chris Brooks in 2013

In 1954, B.R. had about 6,000 steam locomotives falling apart at the rivets so embarked on a programme to replace these with 4 classes of main-line locomotives together with some smaller classes of shunting locomotives. Various manufacturers put forward different types of prototypes and very quickly Sulzer won orders for Types 2, 3, and 4 power units: these being 6, 8 and 12 cylinder LDA28 engines respectively.

Vickers at Barrow in Furness had geared up in the early 50s to produce submarine engines in large quantities in anticipation of an escalation of the war in Korea. This never happened but Vickers had a large works ready to make LDA size engines in great quantity with very quick deliveries, a situation that was recognised by certain people on BR and Sulzers 'father' of Traction-Tom Schur who was head of Dept. 8 in Switzerland where various sizes of LDA engine were already being built for other railway companies.

Sulzer (London) took a license from Winterthur and apart from the first 10 engines built in Switzerland, Vickers built 1,500 engines over a period of 5 years-an engine every working day. This Sulzer order represents the largest single customer contract in the history of Sulzer and will probably stand for all time, a fact stated by Peter Sulzer at the funeral of Tom Schur.

I joined Sulzer London in 1966 when the main build programme was nearly complete and even though I was taken on as a Design Liaison Engineer looking after the flow of information and drawings from Winterthur to Barrow, the duties changed very quickly into those supporting development and service.

At this juncture, I would mention that every industry I've been involved with-automotive, railway, aeronautical and marine, the equipment is never perfect from the word go; hence BR engineers frequently accused us of using them as mobile test beds for development purposes. The railway industry is probably the most arduous duty for any engine because of its cyclic nature. The drivers had come from a steam world where the regulator was either open or closed depending on the speed and gradient. I always wondered as a boy what those boards at the side of the track meant.

DPW-DG70a 1 01.05.2018 When the diesels came along, nothing changed. The Power handles on the control desk were marked 'off', 'on' and 'max', the drivers once under way only moved the handle between 'on' and 'max' depending on the speed they wished to maintain, they never used intermediate positions. The engine governor was even marked 'Stellung Regler', the German for regulator position! Winterthur designed and fitted an electronic governor on D1880, a Type 4 locomotive with a 12LDA28C engine which had both Power and Load control facilities.

We made a test run from London to Leeds and back in both modes with engine speed recording equipment fitted to register the difference. On the outward run we asked the driver to use his usual procedure in power control, but return on load control, as if on cruise control on a modern road vehicle. He had to persuaded to leave the handle alone except when slowing for signals etc. Back in London he thanked us but swore he would never use this mode again because it made him nervous! The readings from the recorder were very different, the outward trace looked like a saw tooth, whereas the return journey trace was a lot smoother with far less speed changes and therefore less load and thermal cycles on the engine.

This cycling imposed huge stresses on all the engine components and led to a process of continual development to increase the time between service intervals and to extend the reliability of the overall power unit. More of this later in the story.

The Sulzer operation in the London office was relatively small in relation to the vast numbers of locomotives coming into service as the main task was to be the communication channel between the specialists in Winterthur and the builders and operators in the UK. At the same time, we had a number of Winterthur engineers working in the London office who acted as on-the-spot liaison staff between Sulzer and BR at a senior level

However, it was always envisaged that the London staff would be expected control the spares and service issues going forward and hence the UK engineers would have to be on a steep learning curve to deal with all the technical issues first hand. The spares operation will be covered later in the story.

In the early years we had about 40 erectors/service personnel at all the engine and locomotive building works such as Vickers Barrow, BR Crewe and Derby, Brush, Beyer Peacock, Darlington and Birmingham Railway Carriage and Wagon. Service engineers were posted at every BR maintenance depot in the UK running Sulzer engined locomotives; they all reported to the London office and regular meetings were held to up- date them with service and development issues.

The work at Vickers covered the construction, assembly and testing of the complete LDA28 power unit, i.e. with its appropriate generator from Brush, GEC, or Crompton Parkinson, depending on the type of locomotive. Whilst Vickers fabricated the bed plates and cylinder blocks, they also made many of the running gear components and ancillary items. This left a great number of parts that came from specialist suppliers, many of whom were well known in British industry. The list would be too large to include here but mention must be made of De Havilland (turbochargers), Specialloyd (pistons), Glacier (bearings),

DPW-DG70a 2 01.05.2018 Vickers Hydraulics (governors), Holset (vibration dampers), Mitchell Shackleton (crankshafts), Bryce Berger, CAV, Wilson and Kyle (fuel injection pumps), Serck (radiators and coolers) and Sheepbridge Stokes (cylinder liners).

In later years, strong relationships with these and other companies were forged through ongoing developments in so many technological fields. At the same time, Winterthur were solidly behind us with their specialist engineers and scientists conducting technical investigations on materials and processes. Examples of this will be covered later under service problems.

Just to enlarge on this aspect, the 12-cylinder LDA double bank engine at it's highest C rating was subject to unacceptable stresses and vibrations in the early years mainly due to the cyclic nature of the service as mentioned above, but partly because of faulty welding techniques at Vickers.

It should be remembered that the LDA28 was a late 1930s design but it won large orders based on its high power/weight ratio due to the double bank design, it met the BR delivery requirements and came from a famous company in the railway industry. In-depth technical expertise on diesel traction was thin on the ground within BR, they were very largely steam engineers and therefore the design details and service experience of diesels was all new to them.

At the same time in 1954, welding and machining techniques were relatively basic compared to what came along-rapidly, during the course of the initial contract and the very long service period of over 40 years!

Knowledge of deep penetration welding was available but its application to the fabrication of bed plates and cylinder blocks left a lot to be desired. Submerged arc welding and computer controlled machines were also unknown at that time.

Although Vickers welding techniques and quality can be criticised, they were certainly in the forefront in other areas. Having built many ships, both merchant, naval and submarines they were absolute experts at gearbox manufacture. The double bank 12LDA was two 6-cylinder engines side by side in integral crankcases and cylinder blocks. The two crankshafts transmitted the power by way of gears known as synchronising gears. These connected the two crankshafts to a third gear driving the generator. Vickers had special machinery (MAAG) for hobbing and grinding these gears and were made in matched sets of three. BR were deeply suspicious of the integrity of the synchronising gears and we were asked to hold 30 sets in stock as spares against future failures. None of these gears were ever needed and eventually BR paid for them at cost price!

The overall size of the contract meant that Vickers had to design and built special machines and jigs to build these engines within the promised delivery times. One of these was the boring machine for the 12LDA crankcases and was designed to ensure that all the bearing saddles on both banks were in line with each other.

Winterthur conducted extensive strain gauge investigations on the test bed and introduced the large rebalancing and derating programme to deal with the problem of structural

DPW-DG70a 3 01.05.2018 failures in the crankcases and cylinder blocks. This involved returning every 12LDA28C engine to Barrow for some welding modifications and rephasing and balancing of the crankshafts. At the same time, the engines were derated from 2750 hp. at 800 rpm. to 2580 hp. at 750 rpm. This considerably improved the reliability of the engines but further stress relieving machining work was necessary on the cylinder blocks and crankcases, this was done at the main works Crewe and Derby.

As mentioned above, driving practices didn't change nor did some of the maintenance procedures, consequently Sulzer were kept very busy investigating problems and searching for solutions. I will list a few of these together with the modifications introduced and it may be realised that the LDA28 engine was on a continuous development programme. Apart from structural problems, the next most troublesome area was the turbocharger. The cyclic running and rapidly changing heat gradients meant that virtually all the components in the turbocharger had to be modified over time. Here again investigations were conducted by many Sulzer departments whose expertise and facilities were always readily available to the Diesel Division. The Research Dept. had the latest equipment for testing materials for bearings, piston rings cylinder liners and particularly exhaust valves. They conducted a series of high temperature strain gauge tests on valve materials which had an influence on all other Sulzer 4-stroke engines. The foundry in Oberwinterthur was the most modern in Europe and were vital in helping us overcome various problems with castings and their materials.

• Turbine casing cracking-strain gauge testing by Winterthur led to a change in the internal wall thickness of the casting. Wtr. • Nozzle ring distortion-change of manufacturing technique from fabricated to precision casting, Wtr. • Gas inlet casing-cracking and distortion-change of material from cast iron to cast steel, Wtr. • Turbine blade-high temperature erosion-change of material and production method, Centrax. • Turbine wheel-change of production method from broaching to wire spark erosion, Vickers, • Impellor fracturing from the spline causing major damage inside-and outside, the turbocharger. Change from spline to peg drive-Wtr., British Airways, Wilson&Kyle. • Cylinder head-cracking across the flame face-change of design and manufacturer, Wtr,, Elmec Engineering. • Cylinder liner cracking under the collar, change of design, material and method of manufacture to centrifugal casting, Wtr., Sheepbridge Stokes. • Bearing problems were not severe but advantage was taken in the light of change of materials on other engines, Wtr., Glacier.

DPW-DG70a 4 01.05.2018 • Exhaust valve head fracture-see above re-material change from HT to Austenitic steel, Wtr., Märkisches Werk. • Piston ring fracturing-change of material, Wellworthy, Daros.

Right from the start, a constant problem was one of keeping fluids in the engine. Joint leakage was always with us, particularly from coolant hoses and bushes. Eventually the Research Dept. of BR built a hose rig at Derby to develop materials and connections to overcome most of the problems. The rubber transition bush which transferred coolant from the cylinder-block to the head was redesigned to eliminate this constant irritation and silicon rubber was introduced on this component and on virtually all other hoses and pipe connections. At the same time this material was also used on the crankcase doors to eliminate oil leaks.

BR set up a Working Group to investigate a series of service problems which were inter- related and Sulzer were naturally involved with this as a permanent member of the Group.

The practices laid down in BR working practices meant that the Maintenance Depots were going their own way when it came to servicing fuel injectors. Despite the advice from Sulzer, Wilson & Kyle and Bryce Berger, they insisted on endlessly grinding nozzle bodies even though the case hardening on the seat had worn through to softer steel. They just would not replace the complete nozzle. I fought them on this my whole 12 years in Traction and even some years in Marine! The Depot passed the injectors as fit for service because they were producing a good spray pattern on the rig. The end result was a rapid deterioration in the fuel injection leading to black smoke exhaust build-up of carbon on the piston head and neat unburnt fuel running down the cylinder wall causing premature liner wear and crankcase oil dilution.

To add to this catalogue of associated problems, when first designed, the Type 4 batteries were never large enough for repeated cold starts and BR couldn't use anti-freeze because of disposal/ecological restrictions (Actually, anti-freeze would have added to the leakage issues mentioned above because it is more 'searching'). So, BR turned to Borax Sodium Metasilicate water treatment and to combat cold weather and poor batteries, they idled the locomotives when not in service!

Put all this together-neat fuel dribbling in at idling speeds causing more oil dilution, cylinder liner glazing due to the oil being washed off, oil carry over into the exhaust system causing fires in the pipes and turbo charger 'hot' components and finally, degradation of the lub. oil meaning more frequent changes. BR even developed a lub. oil recovery plant to 'clean' and re-dose used engine oil when all along the simple solution was to renew the injector nozzle at specified service intervals.

DPW-DG70a 5 01.05.2018 Remark: Part 2, covering “Governing” as well as “After the LDA28 on British Railways”, is foreseen to be published on Sept. 1st, 2018

DPW-DG70a 6 01.05.2018 The editor, Chris Brooks, born in 1939, joined Sulzer London (who were the licensee for the LDA28 engine) in July 1966. Initially in the Dept. 8 Traction Sales. I then transferred to the Erection & Service office. The London manager was Arthur Tayler and the Winterthur director was Tom Schur. During the following years we became purely a service operation but also dealing with modifications and design changes. These were very busy times trying to keep track of 1500 engines in the UK and about 50 in Africa and Australia.

In 1978 I spent 3 months in Winterthur in the Licence dept. under Jo Wach and Fritz Fluck, receiving familiarisation with the organisation of Dept. 7. The people I met during this period set me up for the rest of my career with Sulzer, and I was extremely grateful for all their guidance and understanding.

Upon my return to London, I worked alongside Ted Kennaugh in the Sulzer (UK) Diesel Division. In 1982 I became manager of the combined Traction and Marine dept. I was made Director in 1990. The next big change was the arrival of Wartsila in 1997. This was not a particularly happy time for me because of the huge cultural differences and I readily accepted their offer of early retirement in 1998.

DPW-DG70a: Chris Brooks – Sulzer on British Railways (Part 1) – 1st Edition 01 May 2018

DPW-DG70a 7 01.05.2018