The failure reasons of valve sealing surface easily

Valve sealing surface is one of the important working face of the valve, the material selection is reasonable and its quality, directly affect the function and life of the valve. Because the purpose of the valve is very extensive, so the sealing surface of working condition difference is very big. 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. More valve advisory welcome login WWW. zjxmfm。 Com query