Analysis of the small details of the electric control valve installation

The following is a detailed introduction to the installation of electric control valve.

Basic error limit; Full stroke deviation; Backlash; Dead zone;

If the overhaul of the regulating valve in the original system has been carried out, in addition to the above-mentioned items, the sealing of the old valve's stuffing box and the joints should be checked.

In the use of regulating valves, many of them are not caused by the quality of the regulating valve itself, but are caused by improper installation and use of the regulating valve, such as the installation environment, improper installation location and direction, or unclean lines. Therefore, when the electric control valve is installed and used, pay attention to the following aspects:

(1) The regulating valve is a field instrument. It requires that the ambient temperature should be in the range of -25 to 60°C and the relative humidity is ≤ 95%. If it is installed in open air or high temperature, waterproof and cooling measures should be taken. Wherever there is a source of vibration, keep away from vibration sources or increase anti-vibration measures.

(2) The regulating valve should generally be installed vertically. In special circumstances, it can be tilted. If the tilting angle is large or the valve itself is too heavy, the support of the valve should be increased.

(3) The pipeline for installing the regulating valve is generally not to be too high from the ground or the floor. When the pipeline height is greater than 2m, the platform should be set as much as possible to facilitate the operation of the handwheel and facilitate the maintenance.

(4) Before the installation of the regulating valve, the pipeline shall be cleaned to remove dirt and welding slag. After installation, in order to ensure that no impurities remain in the valve body, the valve should be cleaned again, that is, all the valves should be opened when the medium is passed in, so as not to trap the impurities. After using the handwheel mechanism, it should be restored to its original neutral position.

(5) In order to make the regulating valve continue to operate in the event of failure or maintenance, the bypass valve should be added to the regulating valve. Special attention should also be paid to whether the installation position of the regulating valve meets the requirements of the process.

(6) The electrical part of the electric control valve shall be installed in accordance with the relevant electrical equipment construction requirements. If explosion-proof products are to be installed in accordance with the requirements of the “Electrical Equipment Installation Criteria for Explosion Hazardous Locations”. For example, SBH-type or other six-core or eight-core rubber-mounted cables with an outer diameter of Φ11.3 mm are used for field wiring. In use and maintenance, it is forbidden to open the lid and repair the explosion-proof surface in an explosive place. At the same time, do not injure or scratch the explosion-proof surface in the disassembly and assembly, and restore the original explosion-proof requirements after the maintenance.