How to Judge Industrial Valves

How to Judge Industrial Valves

Industrial valve is an important accessory for controlling the flow of media on industrial pipelines, which can be used to control the flow of various types of fluids such as air, water, steam, various corrosive media, mud, oil, liquid metal and radioactive media.

Industrial valves can be classified according to different standards:

According to the adjustment form, they can be divided into adjustment type, cut-off type, and adjustment cut-off type; according to the valve body material, they can be divided into metal type, non-metal type, and metal valve body lining type; Divided into electric type, pneumatic type, hydraulic type, manual type according to the driving mode; according to the temperature range, it can be divided into ultra-low temperature valve, low temperature valve, normal temperature valve, medium temperature valve, high temperature valve; according to the pressure range, it can be divided into vacuum valve, low pressure valve, medium pressure valve valve, high pressure valve, ultra high pressure valve.

Common industrial valve products include gate valve, globe valve, check valve, safety valve, ball valve, butterfly valve, steam trap, etc. It is mainly composed of valve body, opening and closing mechanism and valve cover, and is widely used in the industry.

In terms of downstream applications, it is currently mainly used in petrochemicals (oil refining units, chemical fiber units, acrylonitrile units, synthetic ammonia units), hydropower stations, metallurgy, marine, food and medicine, environmental protection & sewage treatment, gas, pipelines and rural, urban buildings and rural, Ten areas of urban heating. As an important accessory in industrial production activities, its safety and quality should be considered when selecting it.

Factors for judging the valve:

1. Appearance quality. High-quality industrial valve products should have a smooth surface and no defects such as cracks, shrinkage holes, and blisters.

2. The product logo should be clear, and should be marked with the trademark logo, valve body material code, nominal pressure, nominal size, melting furnace number, product serial number, flow direction and other signs.

3. The strength and sealing test should be carried out one by one before the valve leaves the factory. The upper sealing test must be carried out for those with upper sealing structure, and the two-way sealing test must be carried out for valves without medium flow direction requirements. After passing the test, hang the pressure test qualified mark. If necessary, sampling and re-inspection should be carried out before valve product installation.

4. The valve opening and closing action should be smooth and free of jamming. When using handwheel or handle to operate, the switch direction should be clearly marked, clockwise is closed, counterclockwise is open. The maximum operating force of valve opening and closing should not exceed 350N, which can be operated by one person.

5. The minimum wall thickness of the shell and the minimum diameter of the valve stem are important safety performance indicators of the valve, and should meet the requirements of relevant product standards. Many valve manufacturers cut corners in order to save costs, and the wall thickness of the valve or the diameter of the valve stem has shrunk seriously, which has an adverse effect on the safety of industrial production.

6. Industrial valves with special working conditions or special purposes should be tested to verify whether their performance meets the requirements of standards and use. Such as the flow regulation performance of the regulating valve, the low temperature sealing performance of the low temperature valve, the fire resistance performance of the refractory valve, the steam resistance and drainage performance of the steam trap, etc.