Use valve correctly! Choose the principle of valve

Proper selection of valve, safety production of the guarantee device, the service life of the valve, satisfying the long cycle operation of the device is crucial. The main reason for many valve accidents is the improper selection of valves, such as the use of cast iron valves in cold areas, because the water in the oil is in the valve body, which can easily crack the valves in winter. In some of the outlet valve of the pump body, for some reason, the process is low, but with the pump power is larger, often adopt the method of tube small gate valve to regulate flow, due to the local open gate valve plate, vibration, speeding up the disc and seat sealing surface wear, easy to cause the valve leakage. In addition, the quality of the valve also has a great impact on the production use.

If there is a huge explosion accident at a chemical fertilizer plant, the cause of the accident is identified, which is a liability accident caused by the serious quality problem of the valve. Explosion reason: the second section of the outlet valve withstand the normal working pressure suddenly burst, the check valve failure, system within 0.75 MPa of semiwater gas overflow, rapidly with the ambient air mixed explosive gas space formation, gas chemical explosion. According to the test, the valve has many indicators that do not meet the national standards. In addition, the two kinds of valves are water, steam and oil, non-combustible gas special valves, and the design department is also wrong. Therefore, it is very important to choose the valve correctly for the production, safety and long period of the device.

Choose the principle of valve

The valve shall meet the following basic principles

Reliability in pieces

Petrochemical production requires continuous, stable and long cycle operation. Therefore, the valve should be used with high reliability and safety factor, which can not cause major production safety and casualty accidents due to valve failure. The long period continuous production is the benefit of satisfying the long - cycle operation of the device. In addition, to reduce or avoid the "run, risk, drop, leakage" caused by the valve, create a clean, civilized factory and implement HSE management.

Meet the requirements of process production

The valve shall meet the operating medium, pressure temperature and purpose, which is also the basic requirement of the valve. For example, the valve should be protected by overpressure protection, and the discharge of the excess medium should be the safety valve and overflow valve. Check valves should be used to prevent backflow during operation. It is necessary to automatically discharge the condensate, air and other non-condensable gases that are constantly produced in the steam pipe and equipment, and to prevent the steam escaping, the trap shall be selected. In addition, corrosion resistant materials should be used for corrosion resistant materials.

It is convenient to operate, install and repair

After the valve is safe, the operator should be able to correctly identify the valve direction, the opening mark and the indication signal, so as to handle all kinds of emergency failures in a timely and decisive manner. At the same time, the selected valve type structure should be as simple as possible and easy to install and repair.

Pieces of economy

Pay attention to save investment and reduce the cost of installation. Today's investment is tomorrow's cost. For general occasions, domestic production can meet the requirement of use; domestic valves should be selected; Several different valve types can meet the requirements of use, should choose the low price, simple structure of the valve; The general material can meet the requirements of use, should not choose higher grade material, such as Cr - Mo steel, stainless steel, Babel alloy, etc.