"Richard Smith" wrote in message
...
writes:

On Fri, 18 Aug 2017 15:24:15 +0100, Richard Smith
wrote:

writes:

On Fri, 18 Aug 2017 08:05:27 +0100, Richard Smith
wrote:

Not "clutch".
There were "diesel-hydraulic" locos in Britain.
"Hymek" and "Warship Class" (???).
Were they British "licences" of German designs?
Seems a very German example of precision engineering - not easily
replicated elsewhere.
Advantage is said to be that hydraulic-mechanical transmission
weighed
less than electric transmission, so could pack more punch if the
loco
had to be small and light due to track / axle-load, etc.
Check the real facts if interested.
Used primarily on narrow guage??

Mainline - Standard gauge - Western region of UK. Hilly routes.
https://en.wikipedia.org/wiki/British_Rail_Class_35
https://en.wikipedia.org/wiki/British_Rail_Class_42
Be a royal bitch if it sprung an oil leak!!!
They were also "multi speed" geared transmissions - running on the
short lines in the UK I guess they stood up OK,but I doubt they
would
have lasted long on our transcontinrntals and hauling freight
through
the North American Rockies, or even the appalachians with trains
several miles long.

On huge transcontinental railways you are not limited for loco
size -
so you would not use the hydro-mechanical design to pack a lot of
punch in a small light loco.

http://www.victorianweb.org/technology/railways/23.html
The different conditions here affected engineering practice, for
example we didn't have an abundance of skilled labor while the
frontier was open, so Americans built locos with exposed plumbing and
outside cylinders that were easier to maintain.
-jsw