Wide range of application: apply to the various acids, alkalis, salts, liquid, gaseous media environment, hard seal valves, especially with particles, fibrous media environment. The simple structure of zirconia Seat: valve ball, its performance depends on the material of zirconia ring for the seat of such parts to make full use of zirconia ceramic wear resistant to erosion and corrosion-resistant advantages, while To avoid the weaknesses of its relatively poor metal toughness in structural design adopted three measures: First, based on ceramic materials and high compressive strength and tensile toughness characteristics of cylindrical interference configure a special metal ring, the coefficient of thermal expansion of the metal ring should be close to zirconia ceramic, ceramic cylindrical always in compression, in the seat state, pull out the valve ball seat in frequent impact of the force can be positive or negative offset to prevent the seat due to tensile stress and rupture; The second is the seat of the original metal of the pump (especially some of the fixed seat) wall thickness and thin, increase seat wall thickness does not affect the quality of the pump under the premise, such as supporting the production of wins Island Petroleum Machinery Factory 83mm pump fixed seat, standard size wall thickness of the original 11mm, increased to 15mm improved greatly enhanced seat reliability; Possible to improve the toughness of the ceramic, zirconia ceramic materials pumping valve ball, valve seat, the key to success used. Ceramic materials in general the actual breaking strength is much lower than the theoretical value, the reasons for it? 1920 Griffith (Griffith), brittle fracture theory, that is, the gap in strength theory of brittle materials that material within the original crack, crack the existence of stress concentration caused by the stress of the crack tip is much higher than the average stress, when stress reaches the theoretical strength value at the crack tips, crack rapid expansion and rupture [2]. According to this theory, we can see, Preparation of dense pore-free materials, grain refinement, thus reducing the crack size is one of the effective ways to improve the toughness of ceramics.Read more:Zirconia Ceramic Ball Valve for sale
