Safety Relief Valve, also known as the safety relief valve an automatic pressure relief device driven by the medium pressure. Depending on the application, they are suitable for both safety and relief valves.
In Japan, for example, there are fewer clear definitions of safety valves and relief valves, and the safety devices generally used for boilers and other large energy storage pressure vessels are called safety valves, and those installed on piping or other facilities are called relief valves. However, according to the Ministry of International Trade and Industry’s “Technical Standards for Thermal Power Generation”, safety valves are specified for important parts of the equipment for safety assurance, such as boilers, superheaters, reheaters, etc. The lower side of the pressure reducing valve is also designated as a safety valve. In the case where the lower side of the pressure reducing valve needs to be connected to the boiler and turbine, it is required to install either a relief valve or a safety valve. In this way, safety valves require more reliability than relief valves.
In addition, from the Japanese Ministry of Labor’s high-pressure gas management rules, the Ministry of Transportation and the rules of all levels of shipping associations, the identification of the safe discharge and regulations, we call the valve that guarantees the discharge a safety valve, and the valve that does not guarantee the discharge is called a relief valve. In China, regardless of the full-opening type or micro-opening type is collectively referred to as a safety valve.
I. Overview
Safety valve is a boiler, pressure vessel and other pressure equipment on the important safety accessories. Its action reliability and performance is directly related to the equipment and personal safety, and closely related to energy saving and environmental protection. Some users and design departments in the selection, always choose the wrong model. This paper analyzes the selection of safety valves.
Ⅱ. Definition
The so-called safety valve broadly speaking, including relief valves, from the management rules, directly installed in the steam boiler or a class of pressure vessels, the necessary condition is that must be recognized by the technical supervision department of the valve, narrowly called a safety valve, the other generally referred to as a relief valve. Safety valves and relief valves are very similar in structure and performance, both are in excess of the opening pressure automatically discharge the internal medium to ensure the safety of the production plant. By the dry existence of this essential similarity, people in the use of the two, often mixed, in addition, some production units in the rules also stipulate the choice of which can be. As a result, the differences between the two are often overlooked. Thus, there are many problems. If a clearer definition of the two is to be made, it can be understood in accordance with the definition set forth in the ASME Boiler and Pressure Vessel Code, Title I. The definition of safety valves is as follows:
(1) Safety valve, an automatic pressure relief device actuated by the static pressure of the medium in front of the valve.It is characterized by full opening action and sudden opening. Used for gas or steam occasions.
(2) Relief Valve, also known as the relief valve by the static pressure of the medium in front of the valve to drive the automatic pressure relief device. It is with the pressure over the opening force of the growth and proportional opening. Mainly used for fluid occasions
