Now, many factories in the boring machine by marking the processing of the ball shaft hole. Because the ball shaft hole processed by this method is not the working position of the ball in the valve, the error is large. Failed to meet the drawing requirements. The overall error generated after assembly has a serious impact on the sealing, resulting in valve leakage. It can be seen that if the coaxiality of the upper and lower shaft holes is low, the upper and lower shafts and composite bearings are involved in the assembly to eliminate interference. Only increase the radial dimension of the bearing. Make the contact between the ball and the valve seat produce clearance. The soft sealing pneumatic ball valves such as rubber and tetrafluoroethylene can still meet the requirements of sealing without leakage, but the opening and closing torque and seal ring wear are increased. For the metal sealed pneumatic ball valve, sealing without leakage cannot be achieved. Because the spherical shaft hole is processed by scribing correction. The coaxiality error is 6 ram, and leakage occurs after assembly. In order to meet the requirement of coaxiality, after the sphere is processed, the shaft hole shall be processed on the CNC boring machine or digital display boring machine. Because the diameter accuracy of the boring machine spindle is high, the ball center can be found directly. After the shaft hole on one side is processed, the boring machine workbench rotates 180 degrees, and the spindle of the boring machine is used to calibrate again to process the shaft hole on the other side. The shaft hole processed by this method has high position accuracy and small coaxiality error. The ball of pneumatic ball valve is generally chrome plated on the surface of 1Cr18Ni9Ti or carbon steel. Since the spherical surface has sharp corners formed by channels and shaft holes, according to the electroplating principle, the coating on the sharp corners is thicker, and the deviation between the actual thickness and the average thickness is about 30% or more. Although the ball was grinded after turning, after electroplating, the coating thickness was uneven, and the roundness of the ball was out of tolerance, resulting in leakage between the valve seat and the ball of the metal sealed pneumatic ball valve,

Pneumatic high temperature ball valve: the pneumatic high temperature ball valve uses a new sealing material as the valve seat, and is sealed by the same product PTFE. Its service life has been increased by 3-5 times. It has the advantages of stable performance, reliable sealing, small friction, light switch, high temperature resistance, wear resistance, oil resistance, corrosion resistance, long service life, etc. It is widely used in petroleum, chemical, rubber, paper making, pharmaceutical and other industries, and can replace the stop valve, plunger valve, and quick drain valve.