Looseness of the valve bolt holes: how to prevent loss

This post was last edited by 678-2 on 2016-8-11 at 09:39. In the situation you described, it is possible to carry out the work in accordance with the provisions of 4.2 Valve Inspection, as well as sections 8.6.4, 8.6.5, and 8.6.6 of the \"GB 50235-2010 Code for Construction of Industrial Metal Piping Projects\", and to conduct inspections and acceptance in line with the relevant rules outlined in the \"GB 50184-2011 Code for Acceptance of Construction Quality of Industrial Metal Piping Projects\". For your reference. 4.2.2 Valves shall undergo shell pressure tests and sealing tests; valves with an upper sealing structure shall also undergo an upper sealing test. Those that fail these tests shall not be used. 8.6.4 The hydraulic test shall comply with the following provisions: 11 The pressure shall be increased slowly during the hydraulic test; once the test pressure is reached, it shall be maintained for 10 minutes. Then, the pressure shall be reduced to the design pressure, and it shall be maintained at this level for 30 minutes. It is necessary to check whether there is any drop in pressure on the pressure gauge and whether there are any leaks in all parts of the pipeline. 8.6.5 The pneumatic pressure test shall comply with the following provisions: 5 During the test, the pressure should be increased gradually. When the pressure reaches 50% of the test pressure, if no abnormalities or leaks are detected, the pressure should be increased further in steps of 10% of the test pressure, with each step being held for 3 minutes, until the test pressure is reached. The pressure should be maintained at the test pressure for 10 minutes, after which it should be reduced to the design pressure. A foaming agent should be used to check for any leaks, and the duration of pressure release should be determined based on the requirements of the leak detection process. 8.6.6 The leakage test shall be carried out in accordance with the provisions of the design documents and shall meet the following requirements: 5 The leakage test should involve a gradual increase in pressure step by step; once the test pressure is reached, the pressure should be held for 10 minutes, after which methods such as applying a neutral foaming agent should be used to thoroughly inspect all sealing points, including the valve stuffing boxes, flange or threaded connections, as well as the vent valves, exhaust valves, and drain valves, for any signs of leakage.

Fluffy and airtight – no problem?