Ball body of rupture-preventing heavy-caliber composite ceramic ball valve, composite ceramic ball valve and manufacture methods thereof

Abstract

The invention discloses a ball body of a rupture-preventing heavy-caliber composite ceramic ball valve, the composite ceramic ball valve and manufacture methods of the ball body and the composite ceramic ball valve. The ball body of the rupture-preventing heavy-caliber composite ceramic ball valve is formed by assembling a ceramic cylinder, a metal ring, a left ceramic spherical cap and a right ceramic spherical cap, the metal ring is fixed in the center of the outer wall of the ceramic cylinder, the metal ring is combined with the ceramic cylinder by adopting a hot charging process or cement process, the left and the right ceramic spherical caps are sleeved outside the ceramic cylinder and then transferred to a center line for covering the metal ring, end faces of the left and the right ceramic spherical caps are tightly fitted, high-temperature and high-strength glue is filled between the left and the right ceramic spherical caps and used for firmly adhering the left and the right ceramic spherical caps, and the metal ring is provided with an arc-shaped groove matched with a valve rod or milled with an elliptical hole matched with the valve rod. The invention also discloses the composite ceramic ball valve comprising the ball body, and the manufacture methods of the ball body and the composite ceramic ball valve. With the adoption of the composite ceramic ball valve, the difficulty of incapability of producing the heavy-caliber composite ceramic ball valve is solved.

Description

technical field [0001] The invention relates to a ceramic ball valve used in chemical industry, desulfurization, slurry, ash powder, coal chemical industry and other industries. The ceramic ball valve is suitable for long-life use under high corrosion, high wear, strong scouring or combined harsh working conditions of wear and corrosion. It also relates to a manufacturing method of the ceramic ball valve. Background technique [0002] At present, the fully lined ceramic ball valve is in the initial stage of industrial application, and the engineering ceramic materials used include TZP (zirconia ceramics), ADZ (alumina toughened zirconia composite ceramics), ZTA (zirconia toughened alumina ceramics), alumina engineering Ceramics and silicon nitride engineering ceramics. Among these ceramic ball valves of different materials, the order of working reliability from high to low is: zirconia ceramics, alumina toughened zirconia composite ceramics, silicon nitride ceramics, zircon...

AI Technical Summary

Problems solved by technology

[0003] The second problem is that the production of large-diameter ceramic balls has limitations: the production of ceramic balls is limited by pressing and sintering conditions, and the diameter of the balls can only be made below DN200, and it is difficult to manufacture ceramic ball valves > DN200

The sphere has to be fired at 1600°C for a long time. The wall thickness of the ceramic sphere is extremely uneven. The end is very thin and the middle part is very thick. When the sintering method and process curve are unreasonable, the yield will drop.

The wall thickness difference between the middle part and the edge of the DN150 diameter ball body is > 50mm, and long-term heat preservation is required to ensure that the ball body is completely densely sintered; even though many measures are taken, it is difficult to ensure consistent mechanical properties of the ball body, and sometimes there are port cracks or low internal density. and other defects

For spheres with a diameter of ≥ DN200, because the wall thickness is too thick, the self-heavy weight, the port cannot bear the self-weight during sintering and is prone to cracks, and the thick-walled part in the middle cannot be completely sintered, even if the finished product is not in line with the material index in terms of performance.

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