Self-compensating low-temperature fireproof sealing type top-mounted low-temperature ball valve

Abstract

The invention discloses a self-compensating low-temperature fireproof sealing type top-mounted low-temperature ball valve. The ball valve comprises a valve body, a valve seat, a valve cover, a ball core and a valve rod and further comprises a graphite ring, a sealing loading assembly and a ball core loading assembly installed on the valve body, wherein the inner wall of the valve body or the outer wall of the valve seat is provided with a radial sealing step face, the sealing loading assembly is arranged on one axial side of the graphite ring and applies axial loading force to the graphite ring, the graphite ring is axially pressed on the sealing step face, and the ball core loading assembly is located under the ball core and supported at the bottom of the ball core to apply vertical upward loading force to the ball core. Through automatic compensation of the ball core and sealing fire prevention of the graphite ring, when the ball valve is in a low-temperature environment, the ball core and a sealing ring keep good assembly precision, then the effective sealing performance and stable switching torque of the ball core in the low-temperature environment are guaranteed, the low-temperature sealing performance between the valve body and the valve seat is guaranteed, and the fireproof performance is reliable.

Description

technical field [0001] The invention relates to the technical field of valves, in particular to a self-compensating low-temperature fire-proof sealing type top-entry low-temperature ball valve. Background technique [0002] For the fireproof structure of the top entry cryogenic ball valve seat and valve body, the traditional method is to process a groove on the outer circle of the valve seat, and install a graphite sealing ring in the groove. This installation method makes the graphite sealing ring not self-sealing. performance, its fire resistance and sealing performance are difficult to guarantee. [0003] For the top-entry low-temperature ball valve, the valve core is a ball core, which needs to be precisely positioned with the valve body. The traditional positioning method is to measure the center height of the ball core and compare it with the center height of the flow channel of the valve body. By processing gaskets of different heights To ensure that the core is load...

AI Technical Summary

Problems solved by technology

[0004] The assembly process requires repeated work of assembly, disassembly and measurement for many times. The entire assembly process is relatively cumbersome, and the assembly and debugging process is carried out at room temperature. When the valve works at low temperature, the ball core shrinks and The self-weight of the ball core causes the center position to shift vertically, causing a relative offset between the center height of the ball core and the center height of the valve seat, causing the spherical surface of the ball core to not fully fit the sealing surface of the valve seat, and affecting the sealing performance of the valve.

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