Propane Safety Valve?

[jseaman]

Over the last few days I have been renovating my home made jet engine - it's a fairly simple set up using a CT26 turbo and propane as the fuel. 

I've discovered a feature which must be what plagued me in the past - gas starvation. I have worked back to the point that if I have an open pipe off the 47kg propane cylinder and open the valve slowly, I get a spurt of gas then it stops. If I turn the valve off completely I hear a click and then it will repeat the process the next time I open it. I'm assuming this is some kind of safety measure and wonder if anyone else has a way of dealing with it

Sometimes it must work OK and lets me fire up to 10+ PSI but most of the time I'm limited by gas flow to 3-4 psi and can't use the afterburner at all.

Thanks in advance

James

[racket]

Hi James

Yep , there are madatory safety cutoffs in some countries , especially on things like 9kg-20 lb BBQ cylinders...............its been a problem that has plagued DIY turbine builders for years ,often the only solution is using a "specialist" cylinder that doesn't have them

Cheers
John

[turboron]

jseaman, the 20 pound BBQ tanks in the USA have an Overflow Protection Device (OPD) valve. It shuts immediately if the pressure drop across the valve is too high. That is the reason you need to open the valve slowly to avoid tripping the OPD. They have a triangular valve handle. The older tanks have a water faucet type wheel handle. If you find an older tank it will not have an OPD but you may not be able to get it filled. The only modern USA tanks that do not have an OPD are the 100 pound tanks. I use a 40 pound concrete leveler tank which has an OPD but is allows higher flow than an BBQ tank.

Thanks, Ron

[jseaman]

Oh no!! Well this is bad news, so no workarounds at all then?!

This is a 100lb (47kg) tank but definitely seems to have some protection going on

Is there a way of knowing whether a cylinder has one or not?

[turboron]

jseaman, in the USA tanks with an OPD have a triangular shaped hand wheel valve handle. Tanks without an OPD have a wheel type outdoor water faucet valve handle.

Thanks, Ron