Author Topic: Routing steam engine exhaust up boiler chimney.  (Read 1260 times)

Offline Jasonb

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Re: Routing steam engine exhaust up boiler chimney.
« Reply #15 on: April 04, 2019, 05:20:40 PM »


If 4mm still draughts nicely that sounds a promising place to start  :)


That was for an 1.375" bore engine, your No1 has a 2" bore which will be double the swept volume so twice the amount of exhaust steam to get rid off. You probably want 5.5mm or 6.0mm if working with a load

Offline Gas_mantle

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Re: Routing steam engine exhaust up boiler chimney.
« Reply #16 on: April 04, 2019, 06:09:39 PM »
Thanks, the no1 engine isn't actually mine it belongs to a model engineer who lives nearby but nevertheless I'd like my boiler capable of passing a similar steam volume.

I guess it makes sense to have a few different nozzles to try.

Offline john mills

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Re: Routing steam engine exhaust up boiler chimney.
« Reply #17 on: April 04, 2019, 11:59:20 PM »
As jason said your engines are bigger and would need bigger size nozzle ,as LBSC has in on of his books  excessive back pressure is not required produce an effective blast the speed of  the exhaust steam shooting up the chimney that does the trick.

Offline Gas_mantle

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Re: Routing steam engine exhaust up boiler chimney.
« Reply #18 on: April 12, 2019, 08:05:53 PM »
Many thanks to those who offered advice, I've since upgraded the exhaust and the steam supply pipe to 1/4 which doesn't sound a lot of difference but the new pipe is thinner walled so the bore area is considerably larger.

Needless to say the engine goes twice as fast as it did and has much more power but by god it aint half thirsty running on the hot stuff  :D