The Steam Supply Valve
by John
This valve is the one which opens the steam supply from the boiler to the engine. Triple expansion sgeam engines require a minimum of 100 psi, and preferably 120-200psi. But amteur built boilers are rarely certified above 100 psi.
But compressed air gets to 120 psi with no drama. So guess what will power this engine until I get around to making a high pressure boiler.
So the on-off valve needs to be pretty solid, so it does not explode and send hot fragments of metal in all directions.
Here is the main supply valve as specified and built for my triple expansion steam engine.

The lines in the background are a ruled exercise book, just to give a sense of the scale. There are 9 components of precision machined components in this picture. And about 2-3, 8-12 hr very happy days in the workshop to make. This is all made from bar stock.

And this is the handle which controls the on – off steam supply. Pretty sexy hey?
It all attaches to the high pressure steam chest and cylinder.

Hey! I like this shit stuff . Even if most of the rest of humanity is yawning.
From here it looks like the steam enters the steam chest where there is a stud?
john f
LikeLike
No studs here!
Just an example of change of design. I will plug that hole.
LikeLike
Very nice indeed! I have 301 other projects to get under control before I can get properly stuck back into my Triple project – perhaps I have to look forward to the life of a retired surgeon!
There is a scrawl on the blueprint that says that the engine is a model of the plant from Kuttabul – sank (as AFK) by the Japs in Sydney harbour. The Sydney ferries had the controls at cylinder head level – the engineer’s platform had the top covers sticking through and that steam valve orientated upwards. The reverse gear was via a lever that operated a steam servo that moved the linkage. I have some photos that I have collected, but can’t figure out if i can post them here – email me if you want me to send them
LikeLike
Hi Russell, I would be very interested to see them. My email is jviggers@iinet.net.au
LikeLike