Process Area Activity – [I See Now-08]: Check that one-way valves are not installed in the reverse direction during pressure testing

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Right after graduating, I worked at a shipyard, where I was in charge of project management for pipeline construction. I don’t know anything at all; the workers in the workshop manipulate me at will. I don’t even dare to get angry, because I don’t know how to do things, the managers won’t teach me, and my colleagues don’t understand either. Having spent a lot of time with the workshop master, at my request, he decided to teach me something, namely how to use P&IDs to identify pipes. Well, let’s go check the pipes of the compressed air system. I’m holding the blueprint and checking the pipes – it seems like the direction of this check valve is incorrect, right? It’s installed backwards. It was the first time I had discovered it on my own, and the excitement was indescribable. I quickly asked the workshop technician, and indeed it was reversed. I asked the workers from the construction team, who said it was the foreman who instructed them to install it that way. Well, ask the supervisor. The supervisor said it’s because I’m doing pressure testing to check for leaks; by installing the check valve in the reverse direction, the pressure can be held back, right? Thinking about it, it’s true indeed; by doing the opposite, one can also contain the stress. So I went to find the master and joked with myself about not understanding it. As a result, the workshop technician said, Who told you to install it backwards? Who will pay to fix it if it gets damaged? Oh, now I understand: during pressure testing, the check valve either does not participate in the testing or its disc must be removed; otherwise, it is likely to cause the valve to fail.