boiler test

[bentprop]

After several attempts,I finally have a boiler without leaks.
I intend to run at 30-40 psi,so tested at 100psi:

The pics of the gauge show the pressure after about 4 hours.I'll call it good.
I sealed all plugs etc. with ptfe tape.Is it ok to leave this in,or should it be removed before steaming?If no good,what would I use in it's place?
My threading is all done with taps and dies,and it's not up to the standard where it would hold pressure without some sort of sealing aid.
Also,Firebird's safety valve uses an o-ring,an idea I quite like.Should this be a Viton type,or are normal ones ok for relatively low pressure use,say30-40psi?
Thanks guys.

 

[kd7fhg]

When you are talking about a boiler, you have to think of temperature as well as pressure, a pressure of 40 psi is about 280 Deg F. ( I might be off on the temp, I don't have the saturated steam table in front of me) but what ever you use it will have to withstand heat as well. Teflon tape should be O.K. (looks bad) a Viton O-Ring would be best.

Have a great day!
Rex

 

[zeeprogrammer]

Congratulations Hans.
Do you have a thread showing the build?
I'll be interested in seeing your progress with this.

 

[firebird]

Hi Hans

Nice looking boiler, well done.

With regards to 'O' rings I first used them in the hydraulic pump and they worked just fine. They worked ok in the safety valve as well while testing with cold water. However under steam it didn't work so well and I ended up modifying the valve to take a stainless steel ball. Once modified it worked perfectly. The valve on the boiler of my small steam engine also uses a ball. By all means experiment with 'O' rings but I think you will find balls work better.

Cheers

Rich

 

[mklotz]

When you are talking about a boiler, you have to think of temperature as well as pressure, a pressure of 40 psi is about 280 Deg F. ( I might be off on the temp, I don't have the saturated steam table in front of me) but what ever you use it will have to withstand heat as well. Teflon tape should be O.K. (looks bad) a Viton O-Ring would be best.

For the benefit of present and future readers of this thread, my STEAMT program will calculate the boiling temperature of water as a function of the pressure.

 

[Jasonb]

For sealing steam fittings into bushes you can buy soft copper washers, these come in an assorted pack of various thicknesses so you can get the fitting correctly aligned without undue force.

Jason