Due to the technical principles and structural characteristics of the piston-type single hydraulic props, a weak arc welding seam is provided on the column. The quality of the arc welding seam is difficult to guarantee in technology, although it is in the 5.3.2.5 of the MT112-93 standard. The specific requirements for the tensile strength σb≥500Mpa and elongation δs≥10% of the weld are specified in the article, but the problem of how to detect it at the production site has not been solved, so it often causes failure accidents of the weld, such as: column welds Fractures, leaks in welds, leaks in welds, etc. cause failure of pillars or accidents caused by roof fall. Therefore, the piston single hydraulic prop also has serious safety risks.
At present, the single hydraulic props at home and abroad are welded to the movable column with a three-purpose valve. When the movable column is raised, the operator must rise with it, especially for higher working surfaces, the operator is very uncomfortable. Convenient and unsafe; and the DWX series prop three-purpose valve is set on the handle body. When the liquid is injected, the three-purpose valve will not rise with the rise of the movable column, and is easy to operate, safe and reliable. Each seal point adopts seal compensation and seal tightening technology. When the seal is worn, it can effectively compensate. When the top plate is pressed, it can still maintain the tightening state, reducing the replacement rate of seals and reducing maintenance costs.
Adopt advanced technology for special surface treatment process, so that the prop has the characteristics of anti-corrosion, abrasion resistance and anti-blasting. The working medium uses the underground neutral water of the coal mine, which ensures that the working environment and groundwater are not polluted, and the drinking water in the mining area is also guaranteed. The quality of the product guarantees the health of the people living in the mining area. It is an ideal environmental protection product for coal mining face support. The single hydraulic prop adopts the domestic advanced EDA anticorrosive technology, which doubles the anticorrosive ability of the surface of the living cylinder. In use, even if the surface of the living cylinder is punctured or severely bumped, exposing the substrate will not cause large-area corrosion of the substrate or peeling of the coating. Developed by Beijing Academy of Coal Science and used in our factory for many years, this process has reached the domestic leading level. Zinc-nickel is used, the surface is green-passivated and coated with silicone, and its anti-corrosion ability is more than three times that of galvanizing and phosphating process. Due to the use of zinc-nickel composite coating, the potential difference between the active prop and the coating is reduced, which is not easy to form. The primary battery, when the coating is damaged by impact, produces self-protection ability, which is suitable for use in blasting working faces.
