In the calculation of the SW-6 safety valve, the values of the design pressure and overpressure limit that are entered.

In many practical application scenarios, the design pressure of the SW-6 safety valve is often determined based on the system’s maximum allowable operating pressure. This is to ensure that, in the worst-case scenario, the equipment or system can operate safely without failing or being damaged. When calculating the overpressure limit, it is generally based on the design pressure of the safety valve, that is, a certain percentage of the design pressure, rather than a percentage of the maximum allowable operating pressure. Normally, the overpressure limit is 10% of the design pressure or 10% of the set pressure. However, it should be noted that these regulations may vary depending on different standards or application scenarios. Therefore, in practical operations, it is necessary to refer to the specific design specifications of the relevant equipment or system, or directly consult the manufacturer of the equipment or system to obtain accurate information. .

The discharge capacity of the safety valve should be verified and calculated based on its set pressure.

This post was last edited by Take a look_knkRj on 2023-10-30 at 14:18: page 17 of 150.1, the second line of B3.1 and item B3.2.1. Then looking at the formula for 150, the design pressure is used, so what you said is basically correct; it’s just the value related to the overpressure limit that might be problematic

We generally use the set pressure of the safety valve as a basis for calculations. Sometimes, the set pressure of the safety valve is much lower than the design pressure or the maximum allowable operating pressure; in such cases, it doesn’t seem right to use the design pressure or the maximum allowable operating pressure as the basis for calculations.

Hello, for that overpressure limit, did you choose 10% or something else?

Looking at item B3.2.1 of 150.1, it specifies that the larger of the two values should be used, so it is not necessarily 10%

The discharge pressure calculated for a safety valve – if the setting pressure of the valve is used for this calculation – results in an internal pressure that is much lower than the design pressure, which is a waste of the equipment’s capacity. It releases completely at just a slight overpressure (the internal pressure is far below the design pressure). But following this approach, it should be quite safe

Thank you for the guidance:handshake

If the equipment specifies a maximum allowable operating pressure, then that value should be used； If only the design pressure is provided, it shall be determined based on that design pressure.