1. The packing chamber with vacuum sealing structure is designed, which has the function of self-expanding and compressing, isolates the system from the atmosphere, and has good air tightness and environmental protection performance.

2. Material selection, in line with relevant standards at home and abroad, high quality materials.

3. Seal pair pair advanced and reasonable, improve sealing performance and long service life.

4. Small friction, easy opening and closing, convenient maintenance, reliable sealing and excellent performance.

5. The valve stem is quenched and tempered and nitriding on surface. It has good corrosion resistance, abrasion resistance and abrasion resistance.

6. Flange gaskets are made of composite materials with high expansion coefficient, good air tightness and reliable isolation from the atmosphere.