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The Engineer’s visit to the production line of Britain’s heaviest tank to date marvelled at the production process, but could have had no clue as to what a formidable machine it would turn out to be.
In what was clearly a big deal for our predecessors, the press were invited, for the first time since the Second World War, to tour a Royal Ordnance Factory and see the assembly of what was to become an icon of the Cold War: the Centurion Tank, which saw service in the Korean War, the 1970s Arab-Israeli conflicts, the Vietnam War and even as late as the 1991 Gulf War.
The Centurion was a remarkable vehicle. The heaviest armoured vehicle that had ever been produced in Britain, it weighed 50 tons, was built from 3.5in (88mm) thick steel armour-plate, carried a 3.7in (94mm) calibre gun firing a 20lb (9kg) shell and housed a modified Rolls-Royce Merlin engine — the same one that powered the Spitfire and Lancaster — which gave it a top speed of 25mph (speedy for a tank).
The Engineer reported on the whole production process, including the ingenious welding jigs that rotated the steel-plate hull so that the joints were always presented so that the welders — all working by hand — could wield their welding electrodes downwards and vertically, which maximised the welding current that could be used and minimised the number of welding runs needed. The report also describes how the tank turret was machined out of a single 8.25ton casting. You can read the full report here.
These efforts paid off, as the Centurion was one tough machine — the only tank known to survive a nuclear explosion. In a nuclear test in 1953, a Centurion built the year after The Engineer’s visit was placed 500 yards from the detonation point of a 9.1kt bomb, cleared of crew but fulled loaded with ammunition and with the engine running. After the test, it was found to have been pushed back about 5ft and its engine had stopped — but only because it had run out of fuel; the tank was refuelled and driven away. After repairs, it re-entered military service and stayed in action for 23 years, including 15 months in operational service with the Australian army in the Vietnam War.
Did the chap who drove the tank away glow in the dark for a few days?
I served with REME during my National Service and one of the most interesting courses I attended was on vehicle recovery. The major piece of kit used was an adapted Centurion fitted with a 350 hp winch in place of the gun turret. The instructors told us that the Americans bought British tanks for use as airfield recovery units. A net between two tanks could clear a runway in the event of a crash to allow the next aircraft to land. The Merlin engine was more reliable than their own and would start when needed, so avoiding further accidents.
The production engineering team at the R.O.F. went on to make a “production line” for Chieftain and then Challenger the tanks that followed the Centurion. Much of the external drilling, tapping and facing was effected by portable, universal but heavy duty drilling machines that were easier to move to the job than move the tank hull to a machine. A similar principle applied to much of the internal machining for engine and drive mountings, the machine was lifted into the hull and fastened in place. It was unfortunate that eventually the work dried up and the plant was sold then closed.
I had the great privilege of serving my apprenticeship at the factory in the 1950’s and well remember the production line shown in the old photo’s. The article does not quite get the production process in the three workshops correct. Initial fabrication was in the West shop, Middle shop was main assembly and East shop was paint and stores. Also the article does not mention the auxiliary engine in the tank which was an adapted Morris 8 side valve engine – extremely reliable – coupled to an generator which provided power for start-up, battery charging and power for the electronics. The gun was also fully stabilised via electronics supplied by Metropolitan Vickers.
You need to check your information again. Original gun was a 17 pounder (76mm) and went on th a 20 pounder (84mm). You seem to like spouting off more than checking the details of said spouitng of ‘junk’ basically.
Journalistic standards are slipping all over the place old boy. One day they’re getting the calibre of a 67 year old tank gun wrong, and before you know it they’ll be claiming Archbishop Desmond Tutu built the SS great Britain.
main gun was 17pnd then 20pnd then when i drove them from 1967 to 1971 it was fitted with 105mm fantastic tank and would like a cabby of one again.
ginge anger.1st QDG
The TOG 2 built by William Foster & Co in 1941 as a prototype was 81.3 metric tones. I know nit picking but was a heavier tank and built in the UK.
Interesting set of vibration calcs to the left side, from the days when engineers could share ‘how-to’ information in technical magazines without worrying abut the potential liability issues.
What a fantastic example of British engineering at its best.
Something of a shame when out best involves killing people, but play to your strengths eh?
The piece about the Centurion Tank and 1950 triggered several thoughts. The idea of the turret being a single 8.5 ton casting was amazing: I did once visit a machine-shop in the Liverpool area that contained a series of massive machine tools -reparations taken from Nazi-German machine-shops after 1945: which had been used to make ‘their’ tanks. As an alternative to very large castings, I believe Professor Porsche had experimented with ‘explosive-forming’ of complicated shapes such as turrets as long ago as the early 40s.
I do know that the accuracy of the turret ring machining was critical (so that the angle and hence accuracy/range of the gun was the same whatever angle (horizontal and vertical) it was alligned to!
A very old family friend (who had been a machinist) did once advise that they took some of that technology/skills from the accuracy that was applied to an early textile machine: what is called a “Noble comb” used to process wool fibres.
I noted the name of Timoshenko in the literature references : I thought I had left him (and his horrible -to me, not a particularly good mathematician!) text-books behind when I graduated: but there he is, in the article, haunting me yet again! Best, Mike B
PS during a visit to Budapest in 1985 I met a dear man who was a teenager in 1956! During the up-rising, he had, with fellow ‘terrorists’, helped to develop the ‘soup-plate’ technique for tank-busting. From the restricted view from inside of a Soviet T34 , a row of up-turned soup-plates set across the road looks very like a row of mines: and few tank commanders will venture across such. Whilst stopped at road junctions, the tank is a perfect target for a released (Budapest is built on hills and has a very well developed tram line system) tram: which will up-end a T34 nicely. Unfortunately, they only had a limited number of pieces of tram ammunition! The other manner in which the Soviets assisted their disruptive efforts was to clearly label the auxiliary fuel tank: which happily for them, but unhappily for the occupants was located outside and easily sabotaged.
I hadn’t realised that the Centurian was petrol engine powered? Those who have ever done military service will perhaps recall that the one-time-use small ‘solid-fuel’ heaters used to cook soldiers rations were popularly known as ‘Tommy-cookers’: the same name was given by German soldiers in WWII to Sherman tanks! which were also petrol-engine driven. Mike B
500M from a nuclear bomb eh? Now that’s what I call a tank. Not like these modern tanks that they have these days . Come on British armaments manufacturers, lets get on with Brexit and get back to the good old days of Coronation Chicken sandwiches and unkillable atomic super-tanks! That’ll be one in the eye for the remoaners.
Wasn’t the ground based version on the Merlin called the Meteor?
I seem to remember that The Rolls-Royce Meteor developed from the Merlin, could run on low grade fuel, had a longer service life, and did not have a supercharger. Early versions gave about 500 hp, and 800 in later versions. Some were rebuilt from crashed aircraft. Earliest application was the Cromwell tank, predecessor to the Centurion. See Alec Harvey-Bailey book “The Merlin in Perspective”
Seeing these pictures reminds me of when I trained on the Centurion with a Rolls Royce Meteor MK 4B engine at Catterick in 1956. Driving and maintenance was very hard work.
For driving A plus pass and an A for Maintenance. To this very day at 82 I am sure that I could still remember how to carry out the daily maintenance procedure, I thoroughly enjoyed it.
I was in the 10th royal hussars from55-57. l drove numerous Centurion tanks. Most of my service was in Jordan, BFPO58. Centurion Tanks were magnificent reliable world beaters.A bit thirsty on soft sand(5 galls to the mile)but with 320 galls to go at it still had a fair range. 23136664 Trpr Lake