Ultrahigh-pressure sand-proof plug valve easy to change core

Abstract

The invention relates to an ultrahigh-pressure sand-proof plug valve easy to change a core. The plug valve is characterized in that the small end of a circular truncated cone of a plug cock is downwards and makes contact with the conical surface of a circular truncated cone hole at the center of a wear-resistant bushing; the wear-resisting bushing is arranged in a valve cavity of a valve body, andthe periphery of the wear-resisting bushing is in zero clearance fit with a cylindrical hole of the valve cavity and two symmetrical axial key grooves; the center of a valve cover is provided with avalve rod, a combined sealing piece, a thrust bearing and an O-shaped ring, and the valve cavity of the valve body is sealed and covered with a sealing gasket ring and uniformly distributed screws; the upper end face of the plug cock is connected with a flat key protruding from the lower end of the valve rod through a concave key groove; a one-way valve is arranged between the upper end face of the plug cock and a flow channel hole, and an axial through hole is drilled in a solid body between the upper end face and the lower end face of the plug cock and located at one side of the flow channelhole; one grease injection valve communicating with the upper end of the valve cavity and one grease injection valve communicating with the lower end of the valve cavity are arranged outside one sideof the valve body and outside one side of the valve cover respectively; and after the valve cavity is filled with hydraulic oil, automatic sealing of the plug valve is achieved. The ultrahigh-pressure sand-proof plug valve easy to change the core has the advantages of being simple in structure, easy to machine, reliable in performance, long in service life, convenient to maintain and the like.

Description

technical field [0001] The invention relates to a "cock valve" used in industries such as petroleum and natural gas drilling. Background technique [0002] In oil and gas drilling or fracturing pipelines, plug valves are used instead of flat gate valves for fluid switching control, which has the advantages of simple operation, fast switching, and less safety risks. However, due to the small amount of plug valves with ultra-high pressure and large diameter in the past, relevant parties did not pay enough attention to research, resulting in poor performance and many failures of such domestic plug valves. After investigation, it was found that the main problems: one is that the rubber seal used for sealing between the valve body, the arc and the cock is easily damaged in the high pressure, corrosive and sandy fluid above 70MPa; the other is the different Fluid pressure, for existing plug valves with multiple sealing structures, the movable gaps produced after compressing the s...

AI Technical Summary

Problems solved by technology

However, due to the small amount of plug valves with ultra-high pressure and large diameter in the past, relevant parties did not pay enough attention to research, resulting in poor performance and frequent failures of such domestic plug valves.

After investigation, it was found that the main problems: one is that the rubber seal used for sealing between the valve body, the arc and the cock is easily damaged in the high pressure, corrosive and sandy fluid above 70MPa; the other is the different Fluid pressure, for existing plug valves with multiple sealing structures, the movable gaps produced after compressing the seals are of different sizes, which are very easy to wear sand and fluid leakage; third, the existing plug valve products imitating foreign countries have complex structures, There are many parts and high precision, and it is difficult for ordinary enterprises to guarantee their manufacturing quality; fourth, due to the complex structure and difficult processing of existing plug valve products, the cost and price of products remain high, and the quality and efficiency of use are poor, which inhibits the cooperation between the supply and demand sides. Enthusiasm and Quantity

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