Is a safety valve still needed for the airtightness test?

When conducting a airtightness test, it is still recommended to install a safety valve to ensure safety. Although TSG 21-2016 has removed the requirement that a safety valve must be installed for the airtightness test, this does not mean that the safety of the container can be ignored. Installing a safety valve can reduce the pressure inside the container and prevent accidents such as explosions. Therefore, when conducting a airtightness test, it is still necessary to consider whether to install a safety valve based on the actual circumstances. .

Thank you. Since installing a safety valve requires increasing the calculated maximum operating pressure of the container, are there any cases where no safety valve is used after the new regulations came into effect?

Even though TSG 21-2016 removes the requirement that a safety valve must be installed for airtightness tests, pressure vessels still need to meet certain safety requirements during use, as well as comply with the **specified operating pressures. Therefore, before conducting a airtightness test, it is essential to calculate the maximum operating pressure of the container based on the actual conditions to ensure safety. If it is determined after calculation that a safety valve is not necessary, it is possible to omit its installation during the airtightness test, but this requires thorough calculation and evaluation in advance. At the same time, whether a safety valve is installed or not, the personnel conducting the airtightness test must possess extensive experience and specialized knowledge to ensure that no accidents occur during the test. .

I don’t know where you got those fake technical specifications; there is no version from 2008 – only the 2009 version, which has been obsolete for many years. The regulations require that safety accessories be installed, and even if no such accessories are fitted on the container itself, they still need to be installed in the system. Why are safety accessories required for airtightness tests? Put simply, temperature changes may cause the conditions to exceed the design specifications, or there might be issues with the equipment yet no airtightness test has been conducted.

The new fixed regulations have not abolished it; refer to TSG21-2016, clause 4.1.10.1, which states that \"when conducting a airtightness test, it is generally necessary to have all safety accessories installed.\"

Thank you, I see the new version is written separately

So if the design pressure is different, does one have to buy a matching safety valve for each airtightness test?

On the one hand, it is necessary to follow the standards, and on the other hand, it is also important to take practical circumstances into account. After the airtightness test, try to avoid disassembling or assembling the flange, as it is difficult to determine the airtightness at that time Re-seal airtight? Therefore, the safety valve before airtightness must be installed in place. Pay attention to the setting pressure of the safety valve; verify the airtightness of its associated flanges before this pressure is reached, and close the upstream valve before that pressure is attained to prevent the safety valve from activating. A hermetic system requires a safety valve in place to ensure safety; the safety valve can be selected from those available within the system, or a temporary safety valve for hermeticity can be installed outside the system. It's just my personal opinion; please discuss it among yourselves.

After disassembly, it needs to be rebuilt; pressure vessels that require airtightness must have a maximum allowable working pressure.