Safety Valve Production
Nov 24, 2017
Safety is the top priority of the industry, the safety valve in the safety of the specific role of what? Safety valve which types?
For high temperature, high pressure, flammable, explosive and other continuous production operations, for the safety valve life, running safety, stability requirements are very high. Continuous flow of four parameters need special attention: pressure, temperature, flow, level. To ensure the safety of equipment, production and operation of the stability and personal safety, environmental safety, the following security line:
The first is to control the instrument, if the display of the parameters are not correct, through the manual operation to adjust.
The second is the control system, such as the DCS interlock is set according to the requirements of process safety, in an emergency situation, equipment and equipment into a safe controllable state.
The third is the Emergency Shutdown Device emergency system, which responds to a certain level of safety when the production process is accidentally fluctuating or an emergency requires some action or parking.
The fourth is the safety valve, if the above safety measures are invalid, then the safety valve will take off and pressure relief, to prevent the pressure in the pressure equipment exceeds the design allowable value.
Safety valve is an intrinsically safe protection measures, through the spring force and dielectric force automatically take off, without any manual participation and external force participation, thus preventing the human error caused by the accident. The function of the safety valve is achieved by the following actions: When the system reaches the maximum allowable pressure, the safety valve can be opened accurately and can be discharged stably with the increase of the system pressure and can be discharged at the rated discharge pressure The rated number of working media, when the system pressure down to a certain value should be timely closed, and in the closed state, to maintain the necessary sealing.
Due to production needs, equipment and process requirements and other requirements, the use of safety valve standards are not the same. Commonly used international standards are American Society of Mechanical Engineers (ASME), American Petroleum Standards (API), International Standard (ISO), Japanese Standard (JIS), German Standard (DIN), British Standard (BS), Russian Standard (GHOST ), The commonly used domestic standards are national standards (GB), machinery industry standards (JB) and special equipment safety technical specifications (TSG), the standards of the safety valve regulations have some differences.
Safety valve according to its overall structure and loading mechanism of the different types commonly used for spring-loaded safety valve, balanced bellows safety valve and pilot-type safety valve.
Spring-loaded safety valve is a common safety valve, with the help of the spring to overcome the pressure from the valve below the pressure generated by the force. If the media is not harmful to the person and the environment, such as non-toxic, non-flammable or inexpensive, or inexpensive, such as air, it can be discharged directly into the atmosphere, in which case an ordinary safety valve is used.
Balanced bellows safety valve, the effective area of the bellows is equal to the area of the sealing surface of the valve seat, used to offset the impact of the pressure on the set pressure. Applicable to high temperature and pressure, back pressure or medium can not be directly discharged into the atmosphere of the working conditions.