Diaphragm material for gas attenuator..

[Mechanicboy]

Hi folks!

I created the gas stop valve and gas attenuator.

But the problem is teflon/PTFE sheet is noe easy to buy in Norway.

Can i use the thin silicone sheet as diaphragm cut from the silicone form for baking who is sold by kitchen shop?

The silicone seem soft and strong material and can withstand up to 250 degree Celsius/482 degree Fahrenheit.

Or must it be teflon/PTFE sheet as diaphragm?

 

[Philipintexas]

Not sure I can answer your question, but if you don't get an answer, you could look into using a diaphragm from a small engine carburetor such as a chain saw or lawn-mower. I built one using a part from a Briggs & Stratton engine.

 

[Mechanicboy]

Not sure I can answer your question, but if you don't get an answer, you could look into using a diaphragm from a small engine carburetor such as a chain saw or lawn-mower. I built one using a part from a Briggs & Stratton engine.

Which material is the diaphragm and strong enough against pressure of steam?

 

[dalem9]

Get a gas valve off of a water heater or old furnace .They usually have a big piece in them .

 

[Brian Rupnow]

Mechanicboy--I am interested in running one of my small i.c. engines on propane. Do you have plans which you could share, assuming that that is why you are making this equipment?--Brian Rupnow

 

[Philipintexas]

I think I misunderstood the question, I was thinking of a gas (propane) regulator for running an IC engine on gas.

Did you mean a diaphragm for a steam pressure regulator?

 

[Mechanicboy]

I think I misunderstood the question, I was thinking of a gas (propane) regulator for running an IC engine on gas.

Did you mean a diaphragm for a steam pressure regulator?

Yes,. it's gas attenuator to regulate heat of gasburner affected by steam pressure and the other gas stopvalve to shut of gas to gas burner in case leakage from steam boiler or run empty of the water in the boiler.

 

[Rustkolector]

Brian,
To run an IC engine on propane I highly suggest you build one according to Jerry Howell's plans. Use it with a Weber "Go Anywhere" portable gas grill LP bottle regulator as show here http://www.model-engine-plans.com/engineplans/bookshelf/demandvalve.htm

 

[Blogwitch]

These are two separate items.

One is what Rustcolector has pointed to and I fully endorse the Jerry Howell auto shut of valve using the carb bits. The only thing to watch out for with that design is you need to keep the button pressed on top while the engine is started and has built up enough suction to regulate itself.

A gas attenuator valve is a different kettle of fish, and is only used on model gas fired steam boilers, mainly model boats. It detects the pressure in the boiler on one side of the valve and when the pressure reaches a preset level, it turns the gas flame down, the other end of the valve, until the pressure reaches a lower level and so starts to feed more gas to the burner.
Here is an article written by an old friend of mine explaining how they work and where they are fitted.

http://www.modelboats.co.uk/news/article/boiler-room-part-5-attenuator-valves/8379


John

 

[Mechanicboy]

Today i produced the diaphragm of the silicone from baking form. The silicone is flexible and strong enough to use in the gas attenuator/gas stop valve. I tried to rip off the silicon diaphragm, it was not possible. Easy to cut with a sharp knife to the desired size and punching holes into a sharp edged bolt or sharpened end of the drill. See the picture.. Next i will upload the movie in Youtube.

 

[Mechanicboy]

Picture of the gas stop valve and gas attenuator.

 

[Mechanicboy]

Here is the movie of gas stop valve and gas attenuator..

[ame="https://www.youtube.com/watch?v=t9s3mfysbo0"]https://www.youtube.com/watch?v=t9s3mfysbo0[/ame]

[ame="https://www.youtube.com/watch?v=lPjQHkhnSjw"]https://www.youtube.com/watch?v=lPjQHkhnSjw[/ame]