Some of the factors regulating valve sealing surface material damage

Adjust the sealing face of valve closure piece, is one of the important working face of the valve gate, select material is reasonable and its quality, directly affects the function of regulating valve and longevity. Regulating valve sealing surface of the working conditions because the purpose of regulating valve is very extensive, so the sealing face very different working conditions. Its working pressure can be from vacuum to ultra-high pressure; Working temperature can be from 296 ~ 816 ℃, some occasions working temperature can reach 1200 ℃; Working medium from the corrosive medium to strong corrosive medium such as all kinds of acid and alkali. From the point of force of the sealing surface, it affected by extrusion, shear force; From the point of view of tribology, abrasive wear, corrosion and wear and surface fatigue wear, erosion, etc. Therefore, you should choose according to different working conditions, corresponding to the sealing surface of materials. ( 1) Abrasive wear this is rough, hard surface in the sliding wear occurs when soft surface. Press hard materials into the soft material surface, the sliding wear occurs when soft surface. Press hard materials into the soft material surface, on the surface of contact will draw a small groove. This groove are loose material, in the form of debris or loose particles being pushed away from the surface. ( 2) Abrasive wear metal surface corrosion, produce a layer of oxide. Usually covered in this layer of oxide from corrosion action on the part of that would slow down further corrosion of metal. But if there is a sliding, will remove the surface of the oxide, make bare metal surfaces by further corrosion. ( 3) Surface fatigue wear repeated cyclic loading and unloading, the lower surface or surface causes fatigue crack, fragments and pits in the surface, eventually lead to surface damage. ( 4) Erosion damage of material is produced by sharp particle impact on surfaces. It is similar to abrasive wear, but the surface is rough. ( 5) Scratch scratch is refers to the sealing surface of relative movement in the process of material damage caused by friction.