The process of shell test and seal test of worm fixed ball valve in some artificial environment is as follows. Double blocking and discharge function of worm gear trunnion mounted ball valve: the spring preloaded floating valve seat is used to fix the worm gear trunnion mounted ball valve. When the valve is fully open and fully closed, the fluid is blocked by the valve seat on the upstream and downstream sides, and the discharge valve plays the role of discharging the residue in the cavity of the valve body. Automatic pressure relief function of turbine trunnion mounted ball valve: when the abnormal pressure rise is caused by the temperature rise of the medium in the valve cavity, the automatic pressure relief can be realized only by the valve seat function, and there is no need to relieve the pressure through the safety valve, so the safety is greatly increased when transporting liquid medium.Fire safety structure: valves designed and manufactured in accordance with the specifications of API607 and API FA must have fire safety functions.
Sealing emergency grease injection rescue of worm gear fixed ball: when the accidental failure of the seal is caused by the fire of the valve seat or the blockage of foreign matters in the medium, the grease injection gun will be quickly connected with the grease injection valve, so that the sealing part of the valve seat will be injected with sealing grease in the shortest time, thus alleviating the leakage to a great extent.Reliable valve stem seal box with low operating torque: in addition to the standard seal ring setting, "O" type seal ring is also designed on the packing gland, so the reliability of valve stem seal is greatly enhanced. Under the injection of graphite packing and sealing grease, once a fire occurs, the degree of valve rod leakage will be reduced to the minimum, while under the dual action of valve rod sliding bearing and thrust bearing, the operation of the valve will become extremely simple and convenient. Full bore or reduced bore of worm gear fixed ball valve: the flow aperture of full bore valve can maintain the same size with the inner diameter of the pipeline in the design, so the task of pipeline cleaning becomes very simple. At the same time, the use of full bore or reduced bore structure can be selected according to the demand. The valve stem can be lengthened: for the special needs of cities such as gas or underground pipelines, the valve stem can be lengthened to meet the needs of customers. 8. The worm gear fixed ball valve operates flexibly: the valve seat and valve rod bearing with small friction coefficient and good self lubrication are adopted, which greatly reduces the operating torque of the valve. Therefore, the valve can be operated flexibly for a long time even if no sealing grease is provided