How is the set pressure value for the safety valve determined in a project?
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In a project, how is the set pressure value for the safety valve determined? Is it converted by the local technician, or is it determined directly by the design firm in the equipment list?
The design unit specifies it directly in the equipment list, with the set pressure not exceeding the designed pressure of the equipment.
Generally, it is determined by the design; in practice, process considerations also come into play. Different applications require different pressure values, and the coefficients for pipelines, containers, and boilers vary as well
The constant pressure principle is based on the highest pressure that the equipment can withstand; in other words, the setting of the safety valve is 1.1 times the normal operating pressure. The pressure is set based on the working pressure, or according to the set pressure provided by the customer. When setting the pressure, a spring within the desired pressure range is selected for installation, and then the adjusting nut is used to fine-tune the pressure until it reaches the specified value. A safety valve is a special type of valve in which the closing element remains in a closed position under external forces. When the pressure of the fluid inside a device or pipeline rises above the specified value, this valve releases fluid outside the system to prevent the pressure from exceeding that limit. Safety valves belong to the category of automatic valves and are primarily used in boilers, pressure vessels, and pipelines to ensure that pressure does not exceed specified levels, thereby playing a vital role in protecting both human safety and the proper operation of equipment. Note: The safety valve must undergo a pressure test before it can be used. It is generally provided in the equipment table after being calculated based on the working pressure supplied by the design unit’s client.
Generally, it is confirmed directly by the design unit; the owner can also negotiate with the design unit for adjustments based on the actual process conditions.
The design pressure of some equipment is much higher than the operating pressure; therefore, the design team needs to specify a definite value, otherwise the workshop will not have a basis for setting the pressure.
The last edit to this post was made by gedong456 on 2017-11-16 at 10:47. The design pressure is determined by different requirements regarding the materials to be used; it must be no less than 1.1 times the setting pressure of the safety valve. Other factors such as temperature also need to be taken into account. The operating pressure is fixed, as specified by the process requirements, while the setting pressure of the safety valve is determined with regard to the safety limits for operation