Spring type hydraulic driver for flat gate valve

Abstract

The invention provides a spring type hydraulic driver for a flat gate valve. The driver comprises a driver shell, an upper fixed seat and al lower fixed seat, wherein a piston is arranged in the upper fixed seat and is connected with an ejection rod; a pull rod, a valve rod connecting rod and a spring are also arranged in the driver shell; the pull rod is abutted against the piston; the valve rod connecting rod is connected with the pull rod and is in threaded connection with a valve rod of the flat gate valve; the external diameter of the valve rod connecting rod is greater than that of the valve rod to form a step on the lower end face of the valve rod connecting rod; the lower fixed seat is provided with an internal threaded hole which runs through up and down; an adjusting nut which can move up and down to adjust is in threaded connection with the internal threaded hole; a through hole for the valve rod to movably penetrate is formed in the adjusting nut; the upper end face of the adjusting nut and the step are correspondingly arranged to limit the stroke for downward movement of the valve rod adjusting rod. The driver integrates the various advantages such as adjustable stroke, integral mounting, high stability in mounting and reliability in work; compared with the prior art, the driver has the advantage that the debugging and mounting of the driver are more convenient and faster.

Description

technical field [0001] The invention relates to a single-acting (spring-type) hydraulic driver for a flat gate valve, in particular to a spring-type hydraulic driver with an adjustable stroke and a combination of the whole machine and the flat gate valve. Background technique [0002] Single-acting hydraulic actuators are mainly used in Christmas tree safety valves, choke manifolds, collection pipelines and other equipment. It is a control device that combines common use, large driving force, and uniform and stable operation. However, there are still many deficiencies and urgent improvements in this type of drive, among which problems such as unreliable assembly, various types, inability to realize the assembly of the complete machine and valve, and difficulty in stroke adjustment are more prominent. Specifically, the existing spring-type actuators for slab gate valves mainly have the following technical problems to be solved urgently. [0003] (1) In the prior art, the str...

AI Technical Summary

Problems solved by technology

However, due to the uncertainty of the thread screw-in point, in order to align the hydraulic source oil circuit interface on the driver with the flow channel hole of the valve, usually the thread cannot be tightened, and only the set screw is used to prevent rotation.

Due to the limited space and the size of the main parts, the diameter of the set screw cannot be very large, which directly leads to its extremely limited anti-rotation effect; when the driver is pressed or transported, the thread load changes, the set screw will become loose, and its anti-rotation function At this time, the driver and the valve will rotate relative to each other under the action of vibration or external force, which will directly lead to the change of the valve stroke and cause adverse consequences

[0005] (3) In the prior art, the valve stem of the slab gate valve is threadedly connected to the valve stem connecting rod in the driver, and is equipped with a set screw to prevent rotation, which is similar to the case of the set screw anti-rotation emphasized in (2), During the application and test, the load on the thread between the valve stem and the valve stem connecting rod changes, causing the set screw to loosen, and the relative rotation between the valve stem and the valve stem connecting rod will also affect the stroke of the driver.

In addition, in many cases, the driver will be purchased as a whole or assembled with the valve, and the valve stem and the valve stem connecting rod should be fixed with set screws to prevent rotation, so the driver must be disassembled, resulting in duplication of labor

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