Thread Content
There are many things that cannot be done when installing a valve; they represent the taboos regarding valve installation. For example: the pipeline system needs to be thoroughly flushed, otherwise it will cause failures; hydraulic testing cannot be carried out at negative temperatures, and so on. Next, the editor will continue to explain these situations to you so that you have a clear understanding. 1. The pipeline system should be thoroughly flushed before it is completed; if flushing is not done properly, with insufficient speed and flow rates, it will affect the proper operation of the valves. It can result in water quality not meeting the requirements for the operation of the piping system, and it often leads to pipe blockages or a reduction in the pipe’s cross-sectional area. Measure: Flush using the system’s designed flow rate or a water flow speed of not less than 3 m/s. It is considered acceptable if the transparency of the water color at the inlet is visually consistent with that at the outlet. 2. During winter construction, hydrostatic testing is carried out at negative temperatures. During the hydrostatic test, ice forms rapidly inside the pipes, causing them to be damaged by freezing. Measure: Try to conduct the pressure test before winter installation, and after the test, drain all the water; otherwise, the valves may rust in mild cases or crack due to freezing in severe cases. Therefore, the water inside the valves must be completely removed. If the hydraulic test must be carried out in winter, it is necessary not only to drain all water after the test but also to conduct it at a positive indoor temperature. 3. When conducting integrity tests and hydrostatic strength tests on pipeline systems, it is not sufficient to merely monitor the changes in water level and pressure values. Otherwise, leakage will occur in the pipeline system after it is put into operation, affecting its normal use. Measure: When testing the piping system in accordance with construction specifications and design requirements, it is necessary to carefully check for any leaks, as well as record changes in water level or pressure values within the specified time frame. 4. Ordinary valve flanges are used for butterfly valve flanges. This is because the flanges of ordinary valves and those of butterfly valves vary in size; in some butterfly valves, the valve disc is large while the inner diameter of the flange is small, which prevents the valve from opening or forces it to open, thereby damaging the valve. Measure: The flange should be manufactured according to the actual dimensions of the butterfly valve flange. 5. Rainwater, condensate, and sewage pipes shall be covered up without undergoing a water tightness test. If done this way, it will cause leaks and result in losses for the user. Measure: The water tightness test should be strictly inspected and accepted in accordance with the specifications. For concealed sewage and condensate pipes between pipes, those inside ceilings, those buried underground, as well as rainwater pipes, it is essential to ensure that there are no leaks. The above are the things that should not be done when installing valves; doing so may lead to serious malfunctions, so everyone must keep this in mind.