There are three main processing methods for trapezoidal threads of stainless steel valve stems: turning threads, whirlwind milling threads, and rolling threads. Horizontal lathe cutting trapezoidal threads is a widely used method. The manual tools used for turning threads are simple, with a wide processing range, high thread accuracy, and low Ra value surface roughness. But its efficiency is low, it requires high technical level of workers, and the processing quality is unstable. This processing method can be used when single unit, small batch production, and high thread accuracy are required. In addition, due to the difficulty of whirlwind milling and rolling the trapezoidal threads of the Aoti stainless steel valve stem, most of them are processed by turning.

The corrosion damage of stainless steel ball valve stems is mainly caused by corrosive media. According to the corrosion conditions, the main issue is the filler. In the use of valves, corrosion of the valve stem is inevitable. Therefore, we can only take preventive measures. So, what protective measures should be taken for the valve stem of stainless steel ball valves?

1. When maintaining a ball valve, do not add seals to the valve. Without packing, the valve stem cannot undergo electrochemical conversion and can maintain long-term corrosion resistance.

2. Improve corrosion resistance through surface treatment of ball valve stems.

3. Clean with distilled water to reduce impurities in asbestos pads, reduce the content of chlorine elements and decay in asbestos.

4. Add indirubin to the asbestos pad filler to inhibit the saprophytic activity of chloride complex ions.

5. Protect with polytetrafluoroethylene to reduce packaging spoilage.

6. Improve machining glossiness and reduce electrochemical corrosion.