Talk:SS Jagiełło

Propulsion

"The engine drove twin screw propellers via low pressure turbines" - how does a triple expansion engine drive propellers via turbines? In conjunction with? Nigel Ish (talk) 16:44, 24 June 2020 (UTC)

@Nigel Ish: - probable that the LP turbines were on the driveshafts to the propellers, to give a boost as it were. Mjroots (talk) 18:08, 24 June 2020 (UTC)

When Lloyd's Register says "LP turbines with DR gearing & hydraulic coupling", it can only mean a Bauer-Wach exhaust steam turbine system, which Gustav Bauer and Hans Wach patented in 1926. "Hydraulic coupling" refers to the Föttinger fluid coupling, which was a feature unique to the Bauer-Wach system. The reciprocating engines ran at the same speed as the propellers, and drove them directly via a thrust block and propeller shaft. Steam from each low-pressure cylinder drove a low-pressure turbine, which ran much faster than the propeller. The turbine was geared onto the propeller shaft via double-reduction gearing. The fluid coupling was between the two sets of gears, buffering the smooth-running turbine from the power pulses of the reciprocating engine.

The Bauer-Wach system was in production until at least 1957, by which time it had been installed in about 1,000 ships. Competitors, such as Brown, Boveri & Cie, and White's Marine Engineering Company, circumvented Deutsche Schiff- und Maschinenbau's patents by using different drive trains. Some Scandinavian shipbuilders used chain drive instead of gears. There were a few examples of electric drive from exhaust turbines. If Lloyd's Register does not say "hydraulic coupling", or "fluid coupling", the exhaust turbine system could be from one of those various competitors. Motacilla (talk) 19:08, 22 November 2024 (UTC)