How to maintain the special stop valve for oxygen

1. oxygen stop valve grease, often ignore the amount of grease injection problem. After grease injection and oil filling, the operator selects the valve and grease injection connection mode to carry out grease injection operation. There are two situations: on the one hand, the amount of grease injection is insufficient, and the sealing surface is accelerated by the lack of lubricant. On the other hand, excessive grease injection, resulting in waste. It is that there is no accurate calculation of the sealing capacity of different stop valves according to the valve type category. The sealing capacity can be calculated by the size and category of the stop valve, and then a reasonable amount of grease can be injected.

2. oxygen stop valve grease, often ignore the pressure problem. During the operation of fat injection, the pressure of fat injection changes regularly in peak and valley. The pressure is too low, the seal leaks or fails, the pressure is too high, the grease injection port is blocked, the lipids in the seal are hardened or the sealing ring is locked with the valve ball and the valve plate. Usually, when the pressure of grease injection is too low, the grease injected will flow into the bottom of the valve cavity, which generally occurs in small gate valves. However, if the grease injection pressure is too high, on the one hand, check the grease injection nozzle and replace it if the grease hole is blocked. On the other hand, if the lipids are hardened, cleaning fluid should be used to repeatedly soften the failed sealing grease and inject new grease for replacement. In addition, the sealing type and sealing material also affect the pressure of grease injection. Different sealing forms have different pressure of grease injection. Generally, the pressure of hard seal grease injection is higher than that of soft seal. Ball valve maintenance is generally in the open state, under special circumstances choose to close the maintenance. Other valves cannot be treated as open. The gate valve must be closed during maintenance to ensure that the grease is filled with the sealing groove along the sealing ring. If it is opened, the sealing grease will directly fall into the flow channel or valve cavity, causing waste.

In the operation of the oxygen stop valve, all kinds of valves should be complete and intact. The bolts on the flange and bracket are indispensable, and the thread should be intact without loosening. If the fastening nut on the handwheel is found to be loose, it should be tightened in time to avoid wearing the connection or losing the handwheel and nameplate. If the handwheel of the stop valve is lost, it is not allowed to be replaced by a live wrench, and it should be equipped in time. Packing gland shall not be skewed or have no preload clearance. For cut-off valves that are susceptible to rain, snow, dust, sand and other dirt contamination, the valve stem should be installed with a protective cover. The scale on the stop valve shall be complete, accurate and clear. The lead seal, cap and pneumatic accessories of the globe valve shall be complete and intact. It is not allowed to knock, stand on or support heavy objects on the stop valve in operation. Especially for non-metallic valves and cast iron valves, it is necessary to prohibit the maintenance of valves during grease injection. Professional maintenance of valves before welding and after production plays an important role in serving the production and operation of valves. Correct, orderly and effective maintenance will protect the valves, make them function normally and prolong the service life of valves. Valve maintenance work seems simple, but it is not. There are often neglected aspects of work.