How to deal with the ball spray?

Sphere spraying treatment technology: WC- 12Co is sprayed on the surface of the sphere to form an erosion-resistant coating with a thickness of about 0.3mm and a hardness of 60 ~ 62 HRC. The base of the sealing surface of the valve seat is still processed into a scraper shape, and its surface is also sprayed with a coating with a thickness of 0.3 mm. By changing the spraying process, the hardness of the coating is 55 ~ 58 HRC, and the hardness of the sealing surface of the valve seat is different from that of the spherical surface. After spraying, grind the ball with a diamond grinder until the surface roughness Ra is 0.8 microns, and then match the sealing surface of the valve seat with the ball by hand. Natural diamond powder (particle size 1200 mesh) prepared by adding oleic acid was used as the research material. After grinding the surface roughness of the sealing surface to Ra0.2μm, the sealing is reliable at room temperature.

The products reach: super wear resistance, high temperature resistance (450-1200), erosion resistance, corrosion resistance (salt corrosion, acid corrosion, alkali corrosion, hydrogen sulfide corrosion, etc.) and high pressure resistance (70 Mpa-140Mpa). Bonding strength: more than 10000PSi pounds, smoothness: mirror surface after polishing (within Ra0.2), porosity less than 1%, Vickers hardness of coating about HV 1200 (Yorkshire HRC70), and Vickers hardness of ceramics (bars) about HV/kloc-0.

Use special heating equipment to heat the valve to the design upper limit temperature of 540℃ and keep it for 8 hours. The operation test shows that the valve can be opened and closed flexibly and the sealing test is normal. After repeated experiments, the spherical surface has no obvious change. Because the WC- 12Co coating sprayed on the ball has good thermal hardness and erosion wear resistance, it can still maintain good erosion resistance and scratch resistance even if the temperature rises above the design upper limit of 540℃. Moreover, there is a hardness difference of about 5HRC between the surface hardness of the scraper and the spherical surface. When the cutting edge of the valve seat scratches the coke on the surface of the ball, it will not damage the surface of the ball and the sealing surface of the valve seat, which can ensure the sealing performance and service life.

Commonly used materials such as: nickel-based alloy, cobalt-based alloy, tungsten carbide, various ceramics, high-temperature antioxidant materials, high-temperature thermal insulation materials, various special functional materials, etc.