How to maintain Check Valve, master the basic knowledge to save worry and effort

Today I will introduce to you the application of Check Valve in various situations: Check Valve are an important part of the instrument measuring pipe system, mainly including Check Valve and ball valves. That function is used to open or cut off pipe passages. The valve core of the Needle Valve is a pointed cone that is inserted into the valve seat like a needle, hence its name. The needle valve is easy to install and connect. It has the advantages of fire protection, explosion protection, high pressure resistance, and good sealing performance. It is a Universal Valve with advanced connection methods in power plants, oil refining, chemical equipment, and instrument detection pipelines. The needle valve has good sealing performance and long service life. Even if the sealing surface is damaged, it can continue to be used as long as the easily damaged parts are replaced.

1. How to select Check Valve
① For piping systems and devices with low-temperature media, low-temperature needle valves with a valve cover should be used.
② For the piping system of the catalytic cracking unit of the oil refining unit, a lifting rod needle valve can be used.
③In devices and piping systems with corrosive media such as acids and alkalis in chemical systems, it is advisable to use all-stainless steel needle valves made of austenitic stainless steel and with polytetrafluoroethylene as the valve seat seal.
④ Metal-sealed needle valves can be used for pipeline systems or devices with high-temperature media in metallurgical systems, power systems, petrochemical plants, and urban heating systems.
⑤ For refined oil transportation pipelines and storage equipment, needle valves with welded connections should be used.
⑥ For city gas and natural gas pipelines, needle valves with flange connection and internal thread connection should be used.
2. Precautions for installation of Check Valve
① The installation position, height, and inlet and outlet directions must meet the design requirements. Note that the direction of medium flow should be consistent with the direction of the arrow marked on the valve body, and the connection should be firm and tight.
② The appearance of the Universal Valve must be inspected before installation. The nameplate of the Universal Valve should comply with the current national standards.
③ For Universal Valve whose working pressure is greater than 32.0MPa and which serve as cutoffs on main pipes, strength and tight performance tests should be conducted before installation, and they can only be used after passing the test.
④ During the strength test, the test pressure shall be 1.5 times the nominal pressure, and the duration shall not be less than 5 minutes. The Universal Valve shell and packing shall be qualified if there is no leakage.