Medium through the valve when the flow direction of these changes, so a higher cut-off valve on the flow resistance of the other valve.
介质通过此类阀门时的流动方向发生了变化，因此截止阀的流动阻力较高于其它阀门。
2
Through doing some technical remakes on well resistance furnace the annealing quality of steel wire has been improved and the energy consumption has been cut down.