The first contacting parts of body and sealing seat can be formed into suspended-arm and lip-edge, such as unique design can form a buffing area between the body and sealing ring and automatically compensate the leakage caused by the abrasion of seat, the abrupt variation of temperature and pressure and the deformation of the character of PTFE, moreover, improving the performance of seal and prolong the life span.

The connecting parts of body and bonnet, body and stuffing are sealed with pad, especially, at least the leakage of the connecting parts from hi-temperature or vibration, we design the metal to metal contact between the body and deck, body and stuffing so as to form the fixed flange to prevent the leakage.