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Introduction The following memories are from a worker at Vickers Armstrong, Barrow during the 1960's. Hopefully this will provide a little personal insight into the Workshops that built the vast majority of Sulzer power units that were used in British Railways Sulzer powered locomotives and in a number of locomotives that would operate in Ireland, Australia, Sierra Leone, Nigeria & Malawi. The following notes are recalled from memories of at least forty five years ago, any errors are purely from time blurring or making fuzzy those events recalled! Any corrections or additions are always very welcome. Overview When Terry signed on to Vickers Armstrongs in the early 1960's the following provides a brief overview of the facilities at that time. The site at Barrow was split into two, comprising the Shipbuilding works & the Engineering works. Although both were part of the same company they were run as separate entities with each having its own management & board of directors. The Shipbuilding works obviously built surface ships & submarines, both naval & commercial. The Engineering works were given contracts by the shipbuilders to manufacture equipment to go into these vessels, such items included steam turbines, boilers, condensers, diesel engines, pumps, valves, shafting, gearing, piping etc. The Engineering works also had a great variety of other manufacturing contracts such as: naval armaments, cement making machinery, soap making machinery, mine winding gear, power station equipment etc. etc. Thus Vickers Engineers at Barrow had every engineering manufacturing facility you could imagine. There was a foundry to produce castings, a brass foundry, smithy for forgings, sheet metal shop, pipe shop, gear heat treatment, boiler shop for fabrications, two vast machine shops and three smaller ones. One of the larger machine shops was the General Machine Shop (GMS), it had 12 double-sided bays of machine tools, with a wide central gangway that ran the full length of the shop, set flush into the concrete of this was set a rail tracks which ran outside through the works and connected to the national rail network. The presence of all these facilities and the experience of its workforce would ensure that Vickers Armstrongs were well positioned when negotiating a contract for the manufacture of Sulzer diesels for the British Railways programme. They must also have had a good relationship with Sulzer Bros. of Switzerland as they were already building Sulzer marine diesels under licence. Building an Engine Where does one start with the actual build process of a Sulzer engine? Well first of all at a rough guess I would say that 95% of the engine parts were made in the Barrow works. As far as I can recollect the only parts we didn’t make were:
Crankshafts, drive pinions & generator drive pinions which were supplied by Sulzers, Crankcases & cylinder blocks were fabricated in the Boiler shop by welding steel plates to cast steel frames. These frames form the main bearing housings in the crankcase & the bottom locating rings for the cylinder liners in the cylinder block. During an engine build the bottom flanges of the cylinder block frames are bolted to the top of the flanges of the crankcase frames. After fabrication the block & crankcase undergo numerous machining operations. The aluminium pistons were made in two parts, the top part of the main piston body was machined to about 80 m/m less than the finished diameter and a collar was shrunk on to it. This collar had grooves on the outside to take the piston rings & grooves on the inside, through which oil circulated from the main lubricating oil system, helping to cool the top of the piston. After the collar was shrunk on the complete piston was machined to finished sizes. Various sub-assemblies were done before final assembly. Cylinder heads were fitted with valve guides, valves & springs, studs for inlet manifold, exhaust pipe & water pipe flanges. Valve rockers fitted to their shafts & mounting brackets. The two camshafts were fitted with cams & drive gear pinions. Piston rings were fitted to the pistons along with the con-rod & gudgeon pin. Plus various other small assemblies. All the above were delivered as required to the engine as it was being built. Engine erection was split into two parts, preliminary erection & final erection. Preliminary erection started with the crankcase. The main bearing & gearing bearing bores were checked for size & alignment using mandrels. Any adjustments were made by scraping the bearing bores. The cylinder block was dropped on and temporarily bolted. The camshafts were put in place and the timing gear stub shafts positioned to achieve the correct gear teeth backlashes, and were then drilled & reamed for tapered locating dowels. Similarly the drive end and flywheel end covers were put in place and drilled & reamed for dowels. Any filing, grinding, drilling etc. that was required was done in this area, away from the cleaner final erection area. Everything was then dismantled & cleaned by pressure washing with paraffin in a large tank. While this was been done all the oilways in the two crankshafts were cleaned using wire rods, lint-free cloth and solvent. The oilway access holes were blanked with screwed plugs and the hollow crankpin blanking plates fitted. Final erection began by dropping the crankshafts into the crankcase and fitting the bearing caps. The cylinder block was then dropped into place and secured with bolts & castellated nuts (10 bolts each side of each frame, 7 frames = 140 nuts & bolts to tighten & secure with split pins) After the cast-iron cylinder liners were positioned in the locating bores in the block, the piston & con rod assemblies were lowered in and the big end bearing caps bolted up. Then the cylinder heads were bolted on, there were 8 studs with nuts securing each head, the nuts were first hand tightened, then a compressed-air powered machine with 8 spindles was used, this tightened all the nuts at once to ensure even tightness. After the assembly of these major parts was complete, the ancillary parts were then assembled to the engine. This included: drive coupling & generator drive pinions; flywheel dampers; oil pump; camshafts; rocker assemblies & push rods; fuel pumps; inlet manifolds; exhaust pipes; cooling water pipes; lubricating oil pipes; intercoolers; oil filters; turbo blower; drive end cover & governor; damper end cover; etc. etc. Finally the generator was dropped on and coupled up to the drive pinion flange. Completion & Testing When the engine was complete it would be scrutinised by an inspector who would compile a defect list. The items on this list had to be rectified by the engine fitter and signed off by the Inspector before the engine could go to the test beds for running-in & trials. There were always defects, but mainly they were for things like: a washer missing, or a loose split pin or locking wire. For some reason although a split pin may have had its tails bent round correctly & there was no way it was going to come out, if it could be wobbled around with your fingers it was a defect. The ends of the tails had to be tapped with a hammer & drift into the slot of the castellated nut to make it tight. The engine could now go to the test beds for trials. Before being started up the pipework to and from the engine lub oil pump was disconnected and connected to an external electric pump. This pumped oil from a tank within the test facility via filters through the engine's oilways, all the engine parts could then be checked to see they were getting lubrication. The pump was left running and the engine flushed with oil continuously for 24 hours. The engine was run-in by starting up and increasing the revs by a certain amount every hour, up to maximum. I’m not sure how many hours this took, but it was certainly more than twelve. Full power, overspeed trip & other tests were then performed. Normally testing an engine would mean coupling it to a mechanical dynamometer to apply a load. As these engines powered an electric generator, the load was applied by connecting the output cables of the generator to large heating elements in a huge tank of water, located outside the test facility. In effect a very big electric kettle. After trials were complete one cylinder head & piston were removed from each bank of cylinders and checked for any wear or malfunction, and then re-assembled. The engine was then taken back to the fitting shop and inspected again for any defects. Once these had been rectified and signed off, all the inspection covers were put on and a final coat of paint applied, the engine was then ready for dispatch by rail to the loco builder. The Fitting Shop The fitting shop probably did look a bit chaotic on a photograph, but there was some logic & order in the way it was laid out. The building had three long bays with overhead gantry cranes running the length of each bay. The top end of No.1 bay was where preliminary erection was performed. Halfway down the bay was the paraffin cleaning tank, the bottom end of the bay was for final erection. In No.2 bay there were the administration offices and tool stores in the centre, with benches and steel tables either end of the bay for sub-assembly & inspection activities. No.3 bay was where the cylinder heads & liners were water tested, part of the bay had fitting benches where components from the machine shop were filed, ground & polished to remove sharp edges. At the top end of the building spanning all three bays was the finished parts store. At the other end spanning No.2 & No.3 bay were clean rooms where pistons & con-rods were assembled. A timescale for completing an engine, ignoring the time to machine each component and assemble the sub-assemblies, is difficult now to recall but at a best guess preliminary erection took about a week, final erection about two weeks, running in & testing one week, and another week for final inspection, painting & despatch. Vickers were delivering two engines per week over the duration of the contract. Each engine was worked on by two Fitters & two Apprentices, one of each on dayshift and one of each on nightshift. A Few Memories One little story: The fitter I worked with & myself were called into the test bed one day, they were setting up an engine for testing that we had just completed building. When they tried to bar the engine round by hand prior to starting, it would only turn so far and then locked solid. As the original builders it was down to us to investigate this matter and put it right. We found that one of the inlet manifolds and two of the cylinders were nearly full with oil. The cause of this was the oil drain pipe from the turbocharger, this pipe is in two pieces and when fitted the two halves are joined in the middle with a rubber sleeve & jubilee clips. When these pipes come from the pipe shop they have plastic blanks in the ends to keep dirt out, however these blanks hadn’t been removed before fitting the rubber sleeve. So when the engine was flushed with oil, the turbocharger eventually filled up and overflowed into the inlet manifold and into any cylinder that had open valves. As you can imagine this took quite a bit of time to strip down, clean out and re-build again. We were paid by a bonus system so were not making any bonus for the time it took us to do this extra work, as it was me that fitted the drain pipe originally, I wasn’t too popular for awhile! While I was working in the Fitting shop there was a major problem with the engines that had to be addressed. This problem started because British Railways were reporting that they were finding water leaks from where the cylinder liners sat on the cylinder block. Sulzers solution to this was to modify the cylinder liners by machining a groove around the diameter of the liner, in the corner where it located in the block, and fitting an “O” section rubber sealing ring into the groove. This cured the water leaks but unfortunately twelve months or so later it was the cause of a more serious problem. Some engines in service were sustaining serious breakdown & internal damage caused by a cylinder liner breaking up and dropping. I don’t know how many this happened to, but we had one returned to the Barrow works as it was still within the twelve month warranty period. When we removed the crankcase inspection covers we found that one of the cylinder liners had broken off at its locating flange and dropped, subsequently the piston having no support must have fell sideways and jammed in the crankcase frames. The con-rod had snapped, the mangled piston and what was left of the con-rod was resting upside down on the crankshaft. It must have made a hell of a bang at the time. I don’t know what happened to this engine but I suspect that any good parts were taken off and the crankcase & cylinder block scrapped, as the frames were badly mangled. It was identified that the modified liners were a faulty design, putting the sealing groove in the corner was weakening them and as this groove was adjacent to the combustion chamber the action of heat & water in the groove was causing corrosion in this already weakened area. A programme of repairs was put under way to replace all the cylinder liners that had had the sealing groove modification with the old type, this affected about one hundred engines that were in service. There was a team of two fitters and two apprentices carrying out these repairs at Finsbury Park, London with another similar size team at Sheffield. The programme was later expaned to do this also at Derby (late 1964/early 1965?). I was chosen, along with another apprentice and two fitters to go to Derby on this job. We travelled to Derby by rail and had to change at Preston, where our connecting train was already waiting, but since it was not due to depart for another fifteen minutes we wandered along the platform to the front of the train. The locomotive was a Brush/Sulzer class 47, the driver was out of his cab and standing on the platform, we got chatting to him & asked “What do you think of these loco’s?” He replied “They are the best” At Derby, Sulzers had leased a large workshop from a company called “International Combustion” located in Sinfin Lane. It was quite a large shop and had a rail track running the full length down one side, it was empty bar for the locomotive we were to work on. In one corner covered with a plastic sheet was a brand new diesel engine. I was told this was a prototype Sulzer “R” type, what it was doing there and what it was destined for I didn't know. (Webmaster's note: it is most likely that this was not the R series engine, but one of the 12LVA24 engines delivered to International Combustion for fitting into the bodyshells of the Class 47 influenced design bound for Cuba). When we had completed repairs on this engine, the locomotive was taken outside the shop for running in and testing. The power from the generator was fed into heating elements in an old steam loco’s water tender that sat alongside. We had got the engine run in & it was on a full power test, it was quite an impressive sight, stood there motionless, roaring on full power, exhaust outlets surrounded by a heat haze, roof fans roaring & turbocharger screaming. It was a hot Sunday lunch time in summer & a lot of the workers from the factory were outside eating their lunch, quite a few were stood in front of the loco gazing up in awe as it towered above them, then someone in the loco cab operated the air horns, I’ve never seen a crowd scatter as fast, they must have thought it was going to take off. What struck me about these locomotives was the amount they swayed from side to side on their suspension when the engine was first started up or shut down to a full stop, as opposed to the English Electric powered locomotives which only gave a brief shudder when shutting down, due to the better balance of a “V” engine I suppose. We were only at Derby for two weeks, working on the one engine prior to being recalled to Barrow, I don’t know why but no more repairs were done at Derby. A few months later one of the apprentices who was working on the repairs at Sheffield had to come home sick and I was sent to replace him. The site we were working at was Tinsley Park Motive Power Depot. It was a brand new British Railways diesel maintenance depot, we were modifying two engines a week while we were there. One week we got a message from the boss in Barrow, “Have a day off on Wednesday & don’t go into the depot!” The reason for this was that Lord Beeching was officially opening the depot & they didn’t want him asking awkward questions about problems with the Sulzer engines. I was there for about two months, then the project came to a close. After Tinsley I worked in the fitting shop for about another twelve months, the training policy at Vickers was to periodically move apprentices around the various departments. So I was moved to the General Machine Shop Where I was still involved with Sulzer engines but machining the parts as opposed to assembling them. Vickers were still producing engines up until about the early 70's I think. For a few years after this we were working on various machining contracts for spare parts, mainly cylinder heads, cylinder liners & pistons. Whilst an apprentice at Vickers we came into brief contact with the locomotives that had ben stranded on Anglesey after the Menai Bridge fire. These locos were eventually hoisted aboard a ship one or two at a time and brought to Barrow where they were offloaded onto Vickers dockside. I was an apprentice in the machine shop at the time so it must have been around 1966 or 1967. They were probably brought to Barrow as this was the nearest port with both the crane capacity to lift them & dockside rail track linked to the national rail network. I was working nightshift at the time and a few of us apprentices would sneak out of the workshop in the early hours when it got daylight to have a look at the locomotives that had been unloaded. Since the cabs were not locked we would have a good around inside. Page added May 23rd 2008 |