Early warning stop valve

Abstract

The invention discloses an early warning stop valve. a framework ring sheathed on a valve rod is arranged above an inversed sealing device of a valve bonnet and is provided with a filler A and a filler B, which are sheathed on the valve rod, a filler gland is arranged above the filler B, a spacer bush is arranged between the filler A and the filler B, one middle section of the spacer bush along the length direction of the valve rod is recessed inwards and is provided with a radial through hole communicated with the radial through hole of the spacer bush, a medium leakage detection hole is arranged on a cavity wall of the valve bonnet, and a leakage detection probe is arranged on the medium leakage detection hole so as to trigger a warning facility. The stop valve provided in the inventionis sealed in a multi-stage way so that the detection cycle and the service life of the stop valve are effectively prolonged; and under the situation that the first several sealing stages are invalid and internal medium leakage occurs, the last sealing stage is still effective, and an early warning signal can be generated before the medium is leaked to the outside of the valve.

Description

Technical field [0001] The invention relates to a shut-off valve. Background technique [0002] The shut-off valve is opened and closed by manually rotating the hand wheel to drive the up and down movement of the stem of the shut-off valve, or power-driven up and down movement of the stem of the shut-off valve, which in turn drives the up and down of the valve flap. Most of the existing shut-off valves are primary or secondary sealing. Due to the continuous switching of the shut-off valve, it will inevitably lead to wear between the valve stem and the seal and between the packing, resulting in gaps, which can easily cause the passage of the shut-off valve. The medium leaks. [0003] People continue to improve the shut-off valve, constantly improving the sealing performance of the shut-off valve. For example, the valve disc in the valve body is now integrated with the valve stem, and is sealed on the valve stem by a bellows to achieve the first level of sealing. The isolation of t...

AI Technical Summary

Problems solved by technology

[0004] However, once the above-mentioned sealing fails, when the globe valve is opened, the medium will leak to the outside along the valve stem, through the seal and packing. The higher the pressure, the more serious the situation, especially in the chemical industry. High-risk media, such as: chlorine gas, liquid chlorine, hydrogen fluoride gas, liquefied petroleum gas and strong acid and strong alkali liquid, once leaked, the consequences will be disastrous

[0005] At present, the number of sealing stages of the stop valve is insufficient, and the structure is improper, which leads to a high probability of medium leakage and high maintenance frequency; when the medium leaks, it cannot make a timely alarm to help people make accurate judgments; in normal use, people are very concerned about the stop valve The sealing state of the shut-off valve is unknown, and it is impossible to intervene in advance. Usually, when the medium leaks, it is also the moment when the last stage of the shut-off valve fails. This brings great trouble and danger to the timely maintenance and replacement of the shut-off valve.

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