Main Function of Safety Valves

Safety valves serve as protective devices in systems. When the system pressure exceeds the specified value, the safety valve opens, releasing a portion of the gas/fluid into the atmosphere or outside the pipeline, ensuring that the system pressure does not surpass the allowable limit. This prevents accidents caused by excessive pressure.

Classification of Safety Valves

Safety valves are primarily categorized into two types: spring-loaded and lever-weighted. Spring-loaded safety valves rely on the force of a spring to maintain the seal between the disc and the seat. Lever-weighted safety valves use the force of a lever and a weight. To meet the demands of high capacity, there is also a pulse-type safety valve, also known as a pilot-operated safety valve, which consists of a main safety valve and an auxiliary valve. When the medium pressure in the pipeline exceeds the specified value, the auxiliary valve opens first, allowing the medium to flow through a conduit into the main safety valve, which then opens to reduce the elevated pressure. The discharge capacity of a safety valve depends on the seat diameter and the lift of the disc. Safety valves can be further divided into two types: low-lift, where the lift is between 1/20 to 1/40 of the seat diameter, and full-lift, where the lift is between 1/3 to 1/4. Additionally, based on application requirements, safety valves can be sealed or unsealed. Sealed valves prevent the discharged medium from leaking and direct it entirely through a designated outlet, typically used for toxic or corrosive media. Unsealed valves are generally used for non-toxic or non-corrosive media.

Structure Diagram and Dimension Table