... suspended load,reliable seal,etc., The valve on the X-mass tree adopts a hidden bar,namely a seal ... small switching torque,simple on-line maintenance,etc.The X-mass tree of the integral type wellhead adopts an ... of the pipe columns of the double-pipe integral X-mass tree guarantees the two oil pipes to simultaneously ... C~121°C(LU class) Material class:AA,BB,CC,DD,EE,FF,HH Specification class:PSL 1~4 ...