Value of the burst disc
Thread Content
I recently encountered an issue while reviewing the pressure vessel regulations. According to Article 148, the burst pressure of fixed-pressure vessels must not be higher than the design pressure, nor shall it be lower than 1.05 times the maximum operating pressure. If I set the design pressure at 1.05 times the maximum operating pressure, then it becomes impossible to determine a value for the burst disc. I hope everyone can share their opinions on this
In fact, a burst disc is a safety protection device for fixed-pressure vessels. To ensure the safety of pressure vessels, the lower their burst pressure, the better. Under normal circumstances, the operating pressure is always less than the design pressure, and certainly less than the maximum operating pressure. Based on the situation mentioned by the poster, taking the blasting pressure to be 1 to 1.05 times the maximum operating pressure seems entirely acceptable to me. As long as the safety of the pressure vessel is ensured (which is also the ultimate goal of formulating standard specifications), it doesn’t matter to choose a lower value; there is no need to be constrained by the requirement that it must be at least 1.05 times the maximum operating pressure.
It must not be greater than, nor less than; their intersection is equal to. Under high pressure, the design pressure of the equipment is set at 1.05 times the operating pressure; in this case, the burst disc can certainly use the value of the design pressure.
The design pressure value can be used, but considering the issue of operating ratio, a rupture disc with an operating ratio of nearly 95% is required to function properly; otherwise, under normal operating pressure, frequent pressure fluctuations will cause metal fatigue in the rupture disc, preventing it from working correctly.
It should be greater than or equal to; the design value can be used, but why go to such extreme lengths? The design pressure can be modified; this is not safe, as it also gives the rupture disc some time to rest, otherwise it tends to become fatigued.
When selecting a burst disc, one whose burst pressure is not higher than the design pressure and does not affect normal operation is sufficient.
The tolerance for domestically produced rupture disks is over 5%, while it is said that imported rupture disks can achieve 3% – I’m not sure if this is true