gas main是什么意思

用法例句

The online cladding of corrugated expansion joints of gas mains didn t affect the blast furnace production,saving half the cost of spare parts changing,with the service life of expansion joints being increased twice and the gas pipe net running more safely and reliably.

对煤气主管上的波纹补偿器进行在线包覆,不影响高炉和用户生产,节约一半备件更换费用,补偿器使用寿命增加一倍,煤气管网运行更加安全可靠。