Valve rating and pipeline pressure

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I have a request and hope for an answer The operating pressure of the pipeline is 1.2 MPa, at room temperature; the medium is an acidic liquid with a low concentration. According to standard design practices, the design pressure for pipes is increased by 0.18, and the test pressure is obtained by multiplying this value by 1.5, resulting in 2.07 megapascals. The pipes are made of stainless steel; can a valve with a pressure rating of 16 kilograms be used here? I have two questions: 1. The pipeline pressure test is carried out at 1.5 times the design pressure, which is 2.07, and it takes 10 minutes. The test pressure for the valve is 1.5 times the nominal pressure, which is 2.4; however, this test only takes one minute, and this applies only to the housing. The test pressure for sealing is 1.1 times the nominal pressure, with the test duration being half a minute. In this case, the valve can temporarily withstand the test pressure of the pipeline, but it’s uncertain whether it can hold that pressure for an extended period of time. Additionally, the test pressure for sealing is much lower than that used for pipeline testing; based on this, valves rated at 16 kilograms are not suitable for use. 2. Some people say that pipeline pressure testing is carried out without using valves, with the valves blocked off using blind flanges; if that’s the case, then 16-kilogram valves should be fine as well. Looking forward to an answer!