Valves are not only widely used in various industries, but also used in different environments. Some valves in harsh working environments are prone to problems. Since valves are important equipment, especially for some large valves, it is quite troublesome to repair or replace once a problem occurs. So it is very important to do a good job in daily maintenance and maintenance. Next, Wandekai will take you to understand some little knowledge about valve maintenance.
1. Valve storage and daily inspection
1. The valve should be stored in a dry and ventilated room, and both ends of the passage must be blocked.
2. Valves stored for a long time should be inspected regularly to remove dirt and apply anti-rust oil on the processing surface.
3. After installation, inspection should be carried out regularly, the main inspection items:
(1) Wear of the sealing surface.
(2) The trapezoidal thread wear of the stem and stem nut.
(3) Whether the packing is outdated or invalid, and if it is damaged, it should be replaced in time.
(4) After the valve is overhauled and assembled, the sealing performance test should be carried out.
2. Maintenance work during valve grease injection
The professional maintenance of valves before welding, before putting into production and after putting into production plays a vital role in serving the valve in production and operation. Correct, orderly and effective maintenance will protect the valve, make the valve function normally and prolong the service life of the valve. life. Valve maintenance seems simple, but it is not. There are often overlooked aspects of work.
1. When injecting grease into the valve, the amount of grease injected is often overlooked. After the grease gun is refueled, the operator selects the valve and the grease connection method, and then performs the grease injection operation. There are two situations: on the one hand, the amount of grease injected is insufficient, and the sealing surface wears faster due to lack of lubricant. On the other hand, excessive fat injection causes waste. The reason is that there is no accurate calculation of different valve sealing capacities according to the valve type category. The sealing capacity can be calculated based on the valve size and category, and then a reasonable amount of grease can be injected.
2. When the valve is greased, the pressure problem is often ignored. During the grease injection operation, the grease injection pressure regularly changes in peaks and valleys. The pressure is too low, the seal leaks or the failure pressure is too high, the grease injection port is blocked, the grease in the seal is hardened, or the seal ring is locked with the valve ball and valve plate. Usually, when the grease injection pressure is too low, most of the injected grease flows into the bottom of the valve cavity, which usually occurs in small gate valves. If the grease injection pressure is too high, on the one hand, check the grease nozzle, and replace it if the grease hole is blocked; on the other hand, if the grease is hardened, use cleaning fluid to soften the failed sealing grease repeatedly, and inject new grease to replace it. . In addition, the seal type and seal material also affect the grease injection pressure. Different seal types have different grease injection pressures. Generally, the grease injection pressure of hard seals is higher than that of soft seals.
Doing the above work well is believed to be very helpful to prolong the service life of the valve, and it can also reduce a lot of unnecessary troubles.
