Maximum distance of the branch air supply pipe from the air source distributor to the valve
Thread Content
What is the maximum length of the branch air supply pipe from the air source distributor to the valve?
This post was last edited by jujiangliu on 2016-3-10 at 15:46. Please take a look at SH/T 3020-2013 \"Design Code for Instrument Air Supply in Petrochemical Industries\" and HG/T 20510-2014 \"Design Code for Instrument Air Supply\".
It is not mentioned in either of these two standards. . .
I’ve worked with lengths of 50 to 60 meters; longer lengths are definitely possible as well.
50 meters is definitely no problem; how long do you want? What is a brancher? In our case, it refers to a 4-way branch~
If 6 BAR is supplied to the device, using 8mm pipes, the length is 50–60 meters. Personal experience. A lesson: When an old plant was equipped with new equipment, the pressure in zone 5.5 BAR was applied, along with air pipes of 6 mm in diameter; the length of these pipes was around 30–40 meters. As a result, many control valves did not have sufficient pressure. . .
It is best to use 1/2\" galvanized pipe to lead the tubing near the instrument, and then use 6–10mm pipes to connect it to the instrument.
It becomes insufficient in pressure if it’s too long; I just tested it yesterday
The required air supply pressure for general valves is 0.4 to 0.6 MPag
It is because the air source pressure is low, and the 6mm pipe is thin, which results in a pressure at the valve of less than 4BAR. When using a distributor, it’s best to choose a duct diameter that is one size larger, such as 8 mm, as it’s common for ducts to run distances of 30–40 meters in the field. . . . @jiaguoyun @Big Horse with Big Bow
Generally, 20 or 15 gauge galvanized pipes are used; a gas supply valve is installed nearby, and then an 8mm copper pipe is used to lead the gas to the point of use, with a length of no more than 2 meters, usually 1-1.5 meters. The pressure in the main air line is 6.5, and there is no issue of low air pressure.