Issues regarding installing dual safety valves on containers

It can be said now that they are all double safety valves.

When setting up dual safety valves, the main factors to consider are: 1. The degree of fluctuation in operating pressure； 2 The importance of the pipeline and the impact of shutdown on production. After a safety valve operates, it must be recalibrated as per regulations. This requires closing the valves on both sides, leaving the pipes and equipment without the protection of safety valves; this can have an impact on systems with large pressure fluctuations or on critical pipelines. In such cases, dual valves are installed to ensure that one is in use while the other serves as a backup. Generally, dual safety valves do not discharge simultaneously; it is pointless to use two valves just to ensure a certain discharge volume. In accordance with the standards GB150 or relevant regulations, pressure vessels must be equipped with safety relief devices, but there is no requirement to install two safety valves. But there are those that use a combination of safety valves and rupture discs. As for installing two safety valves, it is generally done from a practicality perspective.

Generally, there are two safety valves, one in use and one as a backup; in some equipment with high discharge volumes, such as boilers, there are still two in use and one as a backup.

How is the \"spare\" part for the safety valve prepared?