In order to ensure the sealing performance of the stainless steel ball valve when the medium operating pressure is low, a certain pre-tightening pressure must be formed between the ball and the sealing seat. In the rigid sealing seat, the reliability and service life of the stainless steel ball valve are clamped in the correct selection of the pre-tightening amount of the sealing seat.
The reliability and service life of stainless steel ball valve; clamp the pre-tightening amount of the correct selection of the sealing seat. The lack of pre-tightening can not ensure the low-pressure tightness of the ball valve: too large pre-tightening will cause the conflicting torque between the ball and the sealing seat to increase, affecting the action function of the stainless steel ball valve; and may cause plastic deformation of the sealing seat, resulting in sealing failure . Regarding the PTFE sealing seat, the preload specific pressure should generally be 0.1 PN and not less than 1.02 MPa.
The adjustment of the pre-tightening amount of the rigid sealing seat is completed by changing the thickness of the sealing adjustment gasket. The processing error of the sealing adjustment gasket will affect the effect of the adjustment: reasonable equipment and adjustment are the key to obtaining excellent sealing performance. In operation, after the seal seat is worn, the active adjustment ability of the preload specific pressure is very poor, so the service life of the rigid seal seat structure ball valve is relatively short.
One of the ways to deal with the problem is to choose a sealing seat with elastic elements. At this moment, the acquisition and adjustment of the pre-tightening amount is no longer dependent on the sealing adjustment gasket but is completed by the elastic element. In addition to obtaining the necessary pre-tightening amount, the sealing seat with elastic elements can also compensate the pre-tightening specific pressure within the elastic deformation range of the elastic element. Therefore, the service life of the ball valve is relatively long.
The key to the sealing of stainless steel ball valves lies in the structure of the sealing seat and the selection of the sealing seat material. According to different structure and application requirements, rationally select the structural method of the sealing seat to ensure the excellent processing technology of the sealing seat: select the sealing material with excellent function and customary application requirements to meet the sealing requirements of the ball valve and advance the reliability and application of the ball valve operation Life span is an important consideration in ball valve improvement planning.
Post time: Nov-10-2020