Large-sized quick opening-and-closing gate-ball combined valve

Abstract

The invention provides large-sized quick open-and-close gate-ball combined valve. The gate-ball combined valve is composed of component parts including a valve casing, a valve spool, a valve seat, a sealing pair, an upper seal and an actuating mechanism and the like. The large-sized open-and-close gate-ball combined valve is characterized in that one sealing element in the sealing pair is made of soft sealing materials, when the valve is on or off, no sliding but only motion in a vertical direction or an opposite direction exists between the sealing pair to ensure the soft sealing materials to be free of rubbing force. In order to achieve above characteristics, the adopted technical scheme includes that sealing force and on-or-off force transmitted to the valve spool are completed by two independent mechanisms, the sealing force of a valve is not preset, an on-or-off process of the valve is performed according to steps of 1), on: releasing the valve spool / value seat prior to moving the valve spool (moving after releasing); and 2), off: moving the value spool prior to sealing the valve spool / valve seat (tightening after moving). The large-sized quick open-or-close gate-ball combined valve has the advantages of reliable sealing, quick on-or-off, high working pressure, low requirement for machining accuracy, low cost, non-preset of the sealing force, small abrasion of sealing surfaces, long service life, easy replacement, small on-or-off torque and small coverage of operation space. Besides, the large-sized quick open-and-close gate-ball combined valve is applicable to various pipe networks built on stilts, ground surfaces and buried deep and the like.

Description

Technical field [0001] The invention relates to a gate valve and a ball valve with a large diameter and rapid opening and closing, and its working pressure includes low, medium and high pressure. Background technique [0002] At present, there are three main types of large-diameter valves: gate valve, ball valve and butterfly valve. The gate valve has a mature structure and reliable sealing, but in large-diameter pipelines, especially when transporting dangerous media (such as gas, flammable and explosive gases), it has gradually been replaced by high price, complex structure and poor sealing performance, opening and closing torque and service life. It is not as good as the ball valve and butterfly valve of the gate valve. The main reason is that the opening and closing speed of the gate valve is too slow. Once the pipe bursts, the medium cannot be cut off quickly. When the pipe is inflammable, explosive or toxic, it will cause the accident to expand further and cause more...

AI Technical Summary

Problems solved by technology

[0015] However, the above component force valve still has the following disadvantages: (1) The cam is used as the side pressure actuator, and the sealing force is limited. In addition, after the enlargement, the sealing force of the valve core is uneven, so the working pressure of the valve is not high. Practice has proved that , its cost performance is not as good as the existing butterfly valve; (2) the sealing part does not use a soft seal, and the required machining accuracy is still very high; (3) a large operating space is required for installation, and when it is used for buried pipe networks, it needs larger valve well

Therefore, the prototype of the patent failed to be industrialized after the successful trial production

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