Are you sure that the CNG was 2000 psi downstream of any regulator or valve?

The parts of the gauge exposed to the fluid need to be compatible. AFAIK, either brass or steel would work with CNG, but you should consult corrosion compatibility data.

Tornado,

Thanks for your comments, yes the Downstream pressure is 2000 psi i am sure about it, because the gauge in the cylinder shows me so. Intercals of the guage which i am usign is Brass.

My biggest concern is even at the begining the gague does not respond.

regards,

Bala.

The cylinder gauge shows only the pressure upstream of any regulator or valve. You need to be sure that the CNG pressure is actually getting into the downstream tank, vessel, and/or piping.

Tornado,

Yes , I agree. Actually, I have the cylinder gague just on the upstream of the valve , so once I open the valve I got the CNG gas at high pressure . The Tube reactor is directely connected to the cylinder via the valve, Just to make sure the pressure getting into the tube reactor i attached the gague to visually feel the increase in pressure inside teh reactor, so this is the gague which does not respond.

regards,

Bala.

Your CNG may still be liquid and flowing as it passes your gauge port....

Try an extension tube between the gauge and the port.

Dear Wal,

Thanks for the suggestion and I see your point. Actually, total length between the monitoring gauage(end of the tube reactor) and the cylinder gauge is around 3 ft in my existing setup, do you suggest to increase more? please advice. (Cylinder pressure is 150 Bar /2175 psi)

P.S: Actually , Before connecting the reactor to the cylinder the workshop guy opened the cylinder regulator to the atmosphere just to let me know the amount of pressure inside the cylinder ( looks crude but kind of confirmation on the presence of CNG under pressure).

Thanks ,

Bala.

I could not advise you and back it up with any citable science.

How hard is it to just try out? Give it a go......?

Shown above is what i am using to fill the 11/4 inch tube with CNG gas around 500 + psi.

The gauge 1 shows the cylinder pressure which is around 2000 PSI but when I open the on/off valve the Gague 2 is not showing any pressure at all. Why so, it suprising ? Is the compressibility fo CNG is playing a role here ? if so please suggest any best and easy way to fill the 1 1/4 tube with CNG gas to around 500 psi.

thanks in advance.

Bala.

If the pressure regulator is of normal construction, the adjustment screw may be turned outward (counter-clockwise). If so, turn it gradually clockwise to increase the downstream pressure. If that doesn't work, the regulator may be malfunctioning.