On 2018-08-08 14:48:54
How to judge whether sealing of high temperature gate valve meets the standard
The gate valve takes the gate plate as the opening and closing part to judge whether an industrial valve product is qualified, the sealing and pressure are two very important indexes. So, exactly how to check whether the high temperature gate valve is qualified? Let's take you to understand.
1. Intermediate pressure test
There are special sealing tests to check the rice tightness of gate valves, such as intermediate pressure test. Intermediate pressure test method: first open the valve plate of the high-temperature gate valve, operate and so on. After the pressure in the gate valve rises to the standard value, lower the gate plate. Then take out the high-temperature gate valve from the pipeline and check the sealing place to see whether there is leakage. In addition to putting the gate valve into the pipeline for the intended test, it is also possible to directly open the top bonnet of the gate valve, inject liquid medium to the standard value, and then check whether there is medium leakage or leakage on both sides of the high-temperature gate valve. No leakage means that the gate valve is well sealed.
2. Pay attention to tests
The preconditions for the accuracy of the intermediate pressure measurement include the following:
1) During the test operation, it is necessary to fill the high-temperature gate valve with medium and liquid medium, such as water or kerosene, to make the pressure in the gate valve chamber reach the specified value.
2) The sealing surface and both sides of the gate valve should be kept clean. Pay attention not to be scratched by the edge during operation.
3) The high-temperature gate valve is used in the pipeline. If the direction of medium transmission has been specified, the intermediate pressure test should also be applied according to the popular pressure of medium.
4) Intermediate pressure test to check the sealing of valve device is limited, only suitable for checking gate valves with nominal diameter above DN32.
In a word, the use of intermediate pressure test method, can be used to check whether the sealing of high temperature gate valve qualified, especially when we are worried about the quality of the gate valve to buy, learn these several detection methods is very necessary.