Naval History Forums

Who can tell me how the diesel engines of the Graf Spee were connceted to the propeller shafts?

Or tell me where I can find that information.

I was Engieering Officer on a US Navy ship that had six diesel engines. The diesel engines were connected to the propeller shafts via electro-magnetic couplings - was it the same for the Graf Spee?

CONDOR

Hi Condor.

That info is difficult to find. According to what I know, four engines were disposed in a "H" form, the vertical arms of the letter were the engines themselves, the horizontal one is a Vulcan (or may be Vulkan) coupling, that connected the engines to the shaft and transmitted the power. I asume the coupling was some kind of clutch, so the engines could be unclutched individually to do maintenance on them.

Thank you Marcelo. That sounds reasonable. Large ocean going multi-diesel driven vessels generally would not have their engines directly connected to the propeller shafts. My Navy ship had 6 engines - three to a shaft - all connected to the propulsion shafts via electrro magnetic couplings. I also sailed on a turbo-electric propulsion ship where the high pressure steam turbine was directly connected to, and drove a generator. The generator produced electrical current that was routed to a lange motor which was mounted on the propeller shaft. Thus the steam turbine rotated in only one direction. However you could increase or decrease the speed of the propeller and the ship, or reverse direction by varying or reversing the electrical current to the motor. Francis Tepedino

Francis, the Vulkan is described as an "hydraulic coupling", may be that that means something to you, as you are speaking of "electro-magentic coupling". I have always supposed that "hydraulic coupling" ment a system like that used to move the Me-109 engine overpressure blower, in which there are two concentrics shafts, one to the engine and the other to the blower, with a film of oil between them. According to the pressure given to the oil, the shafts had some degree of slipage between them, while at high pressure they were efectively locked to each other.

Kind regards

The Graf Spee engines were 6750 hp each the max speed was 475 RPM giving a total of approximatley 54000 hp There were 9 cylinders each engine double acting 2 stroke (meaning fired on the top and bottom of each stroke like a steam engine) They were made by M.A.N. The cylinder Diameter was 420mm and the stroke was 580mm. They could be run as low as 200 RPM. They didnt like heavy oil that had to be heated up to about 80'c thats why they had to be selective at what oil they took from captured ships. There were 8 engines in total (4 engines per shaft twin screw ship) coupled by vulcan couplings and maybe run by one engine each shaft at about 8 knots. The engine units could be dismantled one at a time (9 per engine) as the maintenance was very high on this double acting engine but for its time (1932) it was great technology and got picked up by the Brits mainly Harland & Woolf in their wartime and later B&W engines (100 RPM). Look forwards to some comments. Regards Noel Martin.

I've been curious that the Germans didn't develop this diesel technology further immediately after AGS was constructed, to develop larger engines that could have been used for Scharnhorst or Bismarck. Or better small diesel engines for submarines.

From the brief description given by Detmers in his book about hilfskreuzer Kormoran the four diesel electric engines in that ship in 1940 were of an experimental type with a similar transmission to that adopted eight years earlier for AGS. Ifind it surprising that development, even for civilian purposes, didn't substantially proceed further than it did.

One of the problems faced by the KM was that while Diesel engines were being developed that could power a battleship, the firms involved--primarily MAN, advised Raeder that it would be several years before engines suitable for battleships were ready for production. Herein was the major stumbling block--with diesel powered vessels, the engines are one of the very first things that need be ordered as the engines and their bedding are installed very early in the construction of the hull. Unlike turbines and boilers, which can be installed much later after the hull is mostly complete, the hull must be virtually built around the diesels and essentially become a part of the hull itself. Raeder was unwilling to postpone battleship construction for such a long period of time and this was the main reason he chose to approve steam turbine propulsion.

Diesel electric was also considered, but faced the same problem that there was still considerable time needed for research, development, and testing before units of sufficient power could be put into production. Testing had been going on--and a number of German DE merchant ships had been in part funded by the KM to see how well the system worked, and at least one large liner was under construction which would use very large and powerful DE plants. However, again, Raeder was unwilling to postpone construction until MAN and others showed they could produce dynamos and E-motors of sufficient size and power for battleships.

Ifind it surprising that development, even for civilian purposes, didn't substantially proceed further than it did.

I mentioned previously, that a number of German merchant ships utilized diesel electric drive for propulsion, and that some of these were, in part, funded or subsidized by the KM as test beds for the concept. However, in the merchant world of the 1930s, it was still cheaper to use coal instead of diesel oil and diesel would not necessarily be available in many parts of the world. As a result, it took quite a while for shipping companies to make a switch over to diesel, as many of them had bought interests in coal mines in an effort to maintain a competitive edge in shipping costs.

tommy303 raises some interesting points here. The key point I would think is timescale and also the efficiency and productivity of German engineering companies and shipyards. What was lacking was a sense of urgency, together with proper organisation, which Nazi Germany lacked. Had Raeder - who was not an engineer - pushed the point large diesel engines could have been produced much more quickly, especially if engineers and technicians were not involved in the wasteful ''divide and rule'' projects which flourished courtesy of the Nazi ''leadership.''

Another point is that if Raeder had opted for the Y Plan instead of the ZPlan then Germany could have concentrated on panzerschiffe and the next, improved generation of panzerschiffe instead of the Hipper classe cruisers and the Bismarcks. Engines should not have been a problem then.

The question of oil as against coal shouldn't be problematic either. Oil is more economic as a fuel and requires less labour. Germany did have a sizeable stock of oil fired ships, and again if diesel technology had been promoted by the regime Germany would have been in a far better position to equip its navy. German shipping lines could have been encouraged by subsidy and cost savings into using the required technology, instead of being lumbered with hilfskreuzer such as Kormoran, with its experimental diesel electric engines and too soft metal in its engine bearings, the KM could have had a fleet of hilfskreuzer capable of performing to 20 knots, able to stay at sea as long as Atlantis did - which had its diesel engines in 1932!
Again the problem of dictatorships is a lack of business enterprise.

The MAN double acting 2 stroke engine seems to be a developmental dead end. Unfortunately the American company, H.O.R built some smaller versions under license for use in submarines with disastrous results. The large 2 stroke engines now used in container ships are of the single acting uniflow type developed by Sulzer in next door Switzerland. Possibly MAN had a "not invented here" attitude. In any case it took about 30 years of development to edge out steam power at least at higher levels. I wonder if anyone can fill us in on the early Burmeister and Wain and Sulzer engines.

Hi there, I read this column quite regularly but not much traffic! Anyway have done much research into the "Graf Spee" and the so called vulcan couplings but have not come up with anything of value. So I have gone out on a tangent to a ship called the "Willem Ruys" laid down in Rotterdam before WW2 . This ship survived unfinished until after the war. Then finished with 8 Sulzer engines (4 per screw twin screw) totaling about 20,000HP Now these were coupled by electric magnetic couplings of ASEA Sweden manufacture as early as 1936. I have articles written in 1936 ASEA journel magnetic couplings for large ships and an article in a marine engineering book on the electrical magnetic couplings on the "Willem Ruys" 1948. Now Ive given the size of the MAN engines in my previous posting but can anybody help me out with this so called vulcan coupling and the controlling of and wonder if they were hydraulic couplings. I do believe MAN & B&W have grouped up together now. Regards Noel

Noel,
The Willem Ruys turned out to be a rather infamous and unfortunate ship. Forum members may appreciate this when I mention that this vessel underwent a change of name - to Achille Lauro.

Hi

Noel Martin wrote:but can anybody help me out with this so called vulcan coupling and the controlling of and wonder if they were hydraulic couplings.

It might be that the Vulkan couplings are named after the manufacturing company. Which is located in the Ruhrgebiet and still there. Maybe you can find additional information on www.vulkan.com

regards
ede

From a Kriegsmarine manual:

Thankyou for the last replys 1/ Yes I knew of the name change to Achille Lauro and the problems in the Middle east 1/ The death of a passenge(murdered) & 2/ The fire in the Red Sea and the loss of the ship. It came to Lyttelton once in the late 80s I think and Lyttelton is the port for Christchurch New Zealand ( thats where I live). I have been working on the Graf Spee for a number of years now especially on the mechanics of it. This was because I read a book on the Altmark which was its support ship. The writer said when he was transfered to the Graf Spee as a captured prisoner, the Officers said would you like to see the engine room and then he talked about the 9 shiney pistons on a partially dismantled engine. So thats when it all started for me on this research. So thanks guys. Regards Noel Martin.