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How to do well the pressure test of nodular cast iron manhole cover
Source: clab66.cn Release time: 2023/8/25 15:38:51
The main use of manhole covers is often universal, and the reason why the actual effect is very great should be attributed to its manufacturing process. Then, in order to better improve the quality of goods, it is a very important part to constantly improve the security risks of technical goods. The pig iron well cover can be normally delivered for use only after the pressure test is completed:
1. The manhole cover adopts the high-pressure one-time molding process, with high glass transition temperature, high density, excellent impact peak resistance and tensile strength. However, the load in the whole application process is very heavy, so the stress test should be carried out before the capital is put into operation. The pressure test includes two contents: compressive strength test and density test. Water is generally recommended as a test material. Let's take a look at stress testing methods.
2. After the gas in the pipeline to be tested is removed, the working pressure rises to the specified working pressure value at a stable pressure change rate, and the barometer should be placed as low as possible in the pipeline. Why is the pressure test not conducted before or after the pipeline backfilling? The pipes shall be filled in the gaps without doubt. There are more and more snake tubes. During the pressure test of the well cover, the pipeline shall not change to the original point. The position of the looper flange shall be reflected so as to detect whether there is leakage.
3. The test pressure of the pressure test shall not exceed 1.5 times the working pressure level of the composite well cover material or the working pressure level of the parts with low to medium working pressure level of the management system. If the working pressure gradually rises to the specified test pressure value and stays for enough time to ensure that the pipeline is fully expanded. The whole process takes 2-3 hours. When the management system is stable, the working pressure will rise to 1.5 times of the pressure. If there is no visible leakage or obvious gas pressure during the whole test process, the pipeline will pass the pressure test.
During the pressure test of nodular cast iron manhole cover, it is necessary to first understand what processing technology is used, and then master the appropriate operation process and common problems, so as to better help everyone to ensure the safety of goods. The full coefficient enables the nodular cast iron manhole cover to achieve good practical application results.
