How to deal with the leakage of stainless steel bellows globe valve?

The leakage of stainless steel bellows globe valve is generally divided into internal leakage and external leakage. There are many reasons for leakage. Endocrinology is generally due to the failure of the sealing surface caused by solid impurities in the liquid medium. Combined with the analysis of the on-site usage, the reason for the leakage of the valve stem is mainly related to the valve structure, working environment and operation mode.

Structure The valve stem adopts a double-sealed structure of bellows and packing. Electric ball valve. The bellows are welded with the inner lining ring and the outer lining ring to form a bellows assembly, and then welded with the valve stem and the guide body to block the leakage of the medium through the valve stem. . The valve stem moves up and down from the flat key I upwards until the upper end surface of the flat key I contacts the lower end surface of the lower packing. Since the lower packing is made of PTFE material, if the valve is opened too much, the flat key I will be embedded in the packing, the valve can no longer be opened and closed, and the bellows assembly will be knocked to death, causing the medium to leak along the valve stem. The stretched length and compressed amount of the bellows are determined according to the stroke of the valve. If the stretch or compression exceeds the limit, the bellows may be damaged, causing the small pipe to rupture and seal failure.

What are the technological factors that caused the destruction of the bellows globe valve?
The welding process of the bellows is not perfect: After investigation, the welding process of the bellows is not clear, which leads to the irregular welding process. For example, the corrugated pipe was not fixed with a coaxial tooling before welding, which resulted in the different axis of the corrugated pipe and the valve cavity, irregular grooves of the welded parts, etc., and the corrugated pipe was not protected by a wet cloth during welding. Therefore, this factor is the main reason for the high damage rate of the bellows. Improper handling and storage of valves: After investigation, the process requirements for the handling and storage of the bellows are not clear, resulting in damage to the bellows during the handling and storage. For example, improper handling of the valve will cause the valve bellows to be bent and damaged, and there is no protective measure outside the valve bellows, which makes the bellows easy to cause accidental damage. Therefore, this factor is the main reason for the high damage rate of the bellows.
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