High Pressure gas pipe sizing

Brad White_200

Despite what the Miuras need, the gas company usually dictates a lesser total pressure drop. Also, at least here in MA, we cannot run anything over 14 inches (0.5 PSI) inside a building without a special permit which is difficult to have waived.

By the standards you cite, the 4-inch pipe should be fine and you would have plenty of reserve.

EBEBRATT-Ed

High Pressure gas pipe sizing

Does anyone have a chart for longer legenths and higher pressures? Most of the ones I have seen run out to about 200 feet. We are designing a 500 foot run at 5 psi, 8400 cfh. We think we need 4".

I know there is a long winded equation in the gas code for sizing--one for low pressure and one for high but not being a math wiz I have never been able to make it work. I would like to know how to do it though.

Any math wizzes out their?

Signed,
to cheap to buy software
Ed

Brad White_200

What is

your total allowable pressure drop for the run?

Is the 500 feet the total developed equivalent or are there fittings to be added?

Assuming: If you use 4-inch pipe and allowing for 500 feet plus maybe 20 feet for elbows, you will lose about 0.5 PSIG on the way and have 4.5 PSIG at the end.

If you want to absorb 0.25 PSIG, you will need 5-inch pipe size.

If you can take one ounce pressure drop (0.0625 PSIG) loss, you can get away with 6-inch pipe.

If the standard is 0.30 inches for the run, (0.011 PSIG), you would be at 10-inch pipe, God Help You.

EBEBRATT-Ed

Brad,
thanks for the help.

No 6" or 10" for me! Fittings are minimal I would say 8 90s and 1 valve. The boilers (Miura) require a minimum of 3 psi at the inlet to their gas train.

Have you ever tried that equation??

Ed