... valve, non-rising stem, rising stem, welded, threade, d, union or colar connection end. casting/forging body. API 6A gate valve: ... order to replace the fill of the valve-stem when the valve bears pressure.The seal surface is welded ... preloaded spring, operation torque is little. The wedge valve gate is sealed by wedge seal surface ,it ... Requirement LevelPRl & PR2Working TemperatureK~ V Slab Gate valve