Top-mounted ball valve and assembling tool and process of top-mounted ball valve

Abstract

The invention relates to a top-mounted ball valve and an assembling tool and process of the top-mounted ball valve. The top-mounted ball valve structurally comprises a valve body, a ball body and a valve seat. The valve seat is installed in an inlet and outlet channel of the valve body through a spring seat and a clamping spring by means of the special assembling tool, and the problem that threads are prone to being damaged due to the fact that the valve seat is driven through the threads in the prior art is solved. The requirement for the matching precision between the valve seat and the spring seat is low, parts are easy to machine, assembling and disassembling are convenient, and the assembling quality is reliable.

Description

technical field [0001] The invention belongs to the field of valves, in particular to a top-mounted cryogenic ball valve. The invention is applicable to working conditions of cryogenic medium such as liquid nitrogen and liquid oxygen at -196°C. Background technique [0002] At present, top-entry cryogenic ball valves at home and abroad mostly adopt threaded seat structure or hinged seat structure. The metal seat of the threaded seat structure is installed in the valve body through the threaded ring. In cryogenic conditions, the metal seat and the threaded ring must be made of austenitic stainless steel. Austenitic stainless steel has the characteristics of low hardness and high toughness. When assembling, the valve seat is first retracted into the passages on both sides of the valve cavity by rotating the threaded ring, and the ball is loaded into the valve cavity, and then the threaded ring is reversely rotated to press the valve seat to the ball; the disadvantages are: me...

AI Technical Summary

Problems solved by technology

The metal seat of the threaded seat structure is installed in the valve body through the threaded ring. In cryogenic conditions, the metal seat and the threaded ring must be made of austenitic stainless steel. Austenitic stainless steel has the characteristics of low hardness and high toughness. When assembling, the valve seat is first retracted into the passages on both sides of the valve cavity by rotating the threaded ring, and the ball is loaded into the valve cavity, and then the threaded ring is reversely rotated to press the valve seat to the ball; the disadvantages are: metal valve seat and The threaded ring is made of the same material, and the two threads are easy to bite during assembly, so it is difficult to reliably tighten the thread in place. During the tightening process, uneven force will squeeze, deform and damage the thread teeth, and even drop iron filings to damage the valve seat Soft sealing surface; moreover, the threaded valve seat requires high machining accuracy, precise and suitable clearance and tolerance matching requirements, and difficult processing, especially not suitable for large-diameter cryogenic ball valves

The hinge of the hinge valve seat structure is made of multi-section arc splicing, which is cumbersome to manufacture and troublesome to install, and there is a hidden danger of the hinge joint falling off during use, and the reliability is poor

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