We suggest the use of a model DET expansion tank, the Watts Governor 80 ball cock with integral thermal expansion relief valve, or a 530C calibrated pressure relief valve.
Metal cock ring soft seat surface pressure to the bearing surfaces, such as the valve core and valve seat is concentric ring surface can be a double tight closure.
金属旋塞表面压向阀座环软支座表面，如阀芯和阀座环表面是同心的，就能得到双重严密的关闭。
3
It has the same movement rotated 90 degrees to mention only difference is that Jacket Ball Valvecock body is a sphere, a circular through-hole or channel through its axis.