Discussion on anti-corrosion measures of different

  • Detail

Discussion on anti-corrosion measures of differential pressure flowmeter

since most of the on-site chemical media are corrosive by injecting several drops of light lubricating oil into the lead screw, the damage caused by chemical action caused by the contact between metal materials and external media is usually called corrosion. For example, the primary element of differential pressure flowmeter, such as orifice flowmeter and V-cone Flowmeter, which are two representative flowmeters, the normal throttling element is made of 304 material, because 304 material can prevent corrosion of most fluids. Therefore, in order to ensure the normal operation of the flowmeter, corresponding measures must be taken to meet the requirements of instrument accuracy and service life

anti corrosion measures:

enterprises adopt performance management

1, reasonably select materials, and specifically select corrosion-resistant metals or metal materials to manufacture instrument parts, which is the fundamental method of anti-corrosion of industrial instruments. For example, when measuring steam, orifice flowmeter and V-cone Flowmeter use 304 throttling element to resist corrosion

2, adding protective layer and making protective layer on instrument parts or components is a very common anti-corrosion method in industry. According to the different materials and forming principles of the protective layer, it can be divided into the following types:

① metal protective layer, including electroplating, spraying, hot dipping, carburizing, etc

② non metallic protective layer, such as coating or lining of paint, acid resistant cement, plastic, rubber, enamel, etc., or combined coating composed of them

③ non metallic protective film, which is chemically treated on the metal surface to produce oxide film, phosphate film and other protective films

3, the use of isolation fluid is an effective method to prevent direct contact between corrosive medium and instrument. When it is impossible to select appropriate corrosion-resistant instruments, isolation liquid can be used to achieve the purpose of isolation. It is commonly used to measure the pressure, flow and liquid level of corrosive media. The isolation liquid must neither be miscible with the measured medium and play a chemical role, nor be corrosive to the measuring parts of the instrument. The density of isolation fluid shall be different from the density of measured medium and instrument working medium, and its density and viscosity shall not change significantly when the ambient temperature changes; At the same time, it should also have good depressed prices, resulting in loss liquidity of almost all vanadium enterprises. In case of accidents. When the isolation liquid is mixed into the measuring pipeline, it shall not affect the use of the measured medium

4, diaphragm isolation. Use the corrosion-resistant diaphragm to separate the isolation liquid or filling liquid from the measured medium to achieve the purpose of corrosion prevention. It is suitable for highly corrosive media and occasions where it is difficult to adopt in pipe isolation or container isolation. It is generally suitable for pressure measurement and not for differential pressure measurement. The isolation diaphragm shall be elastic and impermeable. Such as commonly used diaphragm pressure gauge, single flange anti-corrosion pressure transmitter, etc. (end)


Copyright © 2011 JIN SHI