2. The hardening and surface treatment of spheres are three ways to improve the quality of sealing pairs of pneumatic ball valves. The pneumatic ball valve sphere is generally processed by 2Cr13. Its surface hardness is about HB217, which is easy to be damaged not only in working conditions, but also in the process of assembly and testing. Our company adopts solid chromizing process for test, which has been proved to be very effective after one year's practice. After chromizing, the surface hardness is higher than HV1000 degrees. After the carbon steel ball is infiltrated, the surface chromium content is as high as 60% - 80%. After grinding, the corrosion resistance in seawater, nitric acid, acetic acid and other media exceeds that of the impermeable 2Cr13

Development of products in compensator industry and forming of corrugated compensator
Since the reform and opening up, the compensator industry in China has been greatly developed and improved. The output has increased significantly, the product types and specifications have been rich from time to time, the production quality has improved from time to time, and the technical level has been improved from time to time. However, the compensator industry is also facing more and more problems. In order to develop the compensator industry, we must make great efforts to improve the degree of product localization.
Judging from the development of the industry in recent years, the competitiveness of the compensator market can no longer meet the needs of the rapid development of the national economy, and its own situation can no longer meet the complex market competition, leading to the high-end market being monopolized by foreign enterprises. With the deepening of the 12th Five Year Plan, how to improve the localization of compensator products in the new era is a problem that every compensator consumer needs to think about.
However, since the end of 2014, the road of compensator localization has become very smooth. At present, the compensator industry has become a catalyst for the high-end development of domestic pipeline accessories manufacturing industry. During the 12th Five Year Plan period, China will further strengthen the localization of pipeline accessories. At present, there are a large number of domestic compensator enterprises, and the development of the compensator industry is relatively mature, especially the compensator (contraction joint), non-metallic compensator, constant force support and hanger, spring support and hanger, pneumatic butterfly valve, non-metallic contraction joint and other products have been well developed.
With the competition between enterprises in the compensator industry and the competition between production, quality and safety, the compensator products will be developed in the direction of high technology, high parameters, strong corrosion resistance and long life. Under the huge demand environment, the domestic compensator manufacturing industry will also show a better development prospect.
Precautions for forming operation of corrugated compensator:
1. Positioning support height
The spacing approximately equal to the single wave development length is taken as the positioning support height along the axial direction of the outer wall of the tube blank.
2. Reinforced bellows
The outer reinforcing ring can be formed together with the outer reinforcing ring. The outer reinforcing ring can play the role of a local die. After forming and demoulding, the ring becomes a part of the bellows.
3. Moving speed of hydraulic press
The moving speed is too fast, the forming quality is poor, and the springback is large, which is easy to produce waste products; If it is too slow, the consumption efficiency will be low. Generally, the moving speed of the hydraulic press should be controlled according to the nature of the data and the structure of the bellows.