Safety valve is a more special branch of the valve family, its particularity is different from other valves only play the role of switch, more important is to protect the safety of equipment. With the rapid development of China's economic construction, there are more and more equipment projects with pressure control. In view of the equipment pressure relief needs, the PVDF Safety Valve plays a vital role in protecting the equipment process. Safety valves are important safety accessories for boilers, pressure vessels, and other stressed equipment. The Safety valve, also known as the pressure relief valve, is automatically opened and closed according to the working pressure (working temperature) of the pressure system, and is generally installed in the closed system of equipment or pipeline protection system safety. When the pressure or temperature in the equipment or pipe exceeds the set pressure of the PVC Back Pressure Valve, open the pressure relief or cooling automatically, to ensure that the medium pressure (temperature) in the equipment and pipe is under the set pressure (temperature), protect the normal operation of the equipment and pipe, prevent accidents and reduce losses. PVC Safety Valve is mainly widely used in: steam boiler, LPG automobile tank truck or LPG railway tank truck, oil production well, steam power generation equipment of high pressure bypass, pressure pipeline, pressure vessel, etc. Safety valves are generally divided into spring type safety valve, lever type safety valve and pulse type safety valve, among which spring type safety valve is the most common application; including threaded safety valve and flange safety valve. CPVC Safety Valve diameter is generally not large, commonly used between DN15mm-DN80mm, more than 150mm is generally called a large diameter safety valve.
Common safety valves generally have the following types:
1. According to the overall structure and loading structure, it can be divided into heavy hammer lever safety valve, spring safety valve and control type.
2. According to the ratio of valve flap opening height and valve circulation diameter, it can be divided into micro-start type and full-start safety valve.
3. According to the gas emission mode of the safety valve, it can be divided into fully closed, semi-closed and open three types.
The selection of a suitable PVC Pressure Reduce Valve should be considered from the following aspects:
1. Structure and form mainly depends on the process conditions, working media and characteristics of the equipment. General boiler, pressure vessel discharge volume is not large to choose spring safety valve, otherwise the choice of fully open safety valve is better.
2. If the medium is toxic, flammable and explosive, a closed safety valve should be selected.
3. Each safety valve has its own working pressure range, and it should be selected according to the actual requirements.
4. The discharge volume of the selected safety valve must be greater than the discharge volume of the equipment, so as to ensure that part of the medium is excluded and avoid the pressure continues to rise.
Installation Notes:
1. All kinds of safety valves should be installed vertically.
2. There should be no resistance at the outlet of the PP back pressure valve to avoid the compression phenomenon.
3. The safety valve should be specially tested and sealed before installation.
4. The safety valve in use should be checked regularly.