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It is necessary to improve the anti-corrosion and anti fouling capabilities of valves

  • 5251 Views
  • 2014-10-07
At present, the injection one-way valve of the three purpose valve for single hydraulic props in China has been equipped with a ball valve structure for many years. In underground use, it is easy to accumulate coal powder in the injection hole of the one-way valve seat, which is carried into the single hydraulic props during injection. At the same time, the concentricity of the ball valve core is poor, and during liquid injection, the position of the ball will rotate, causing coal dust to be trapped on the sealing surface, leading to slow leakage. The unloading valve adopts a flat convex structure sealing type, resulting in a lower strength of the left valve barrel of the three purpose valve. After the valve barrel is corroded, repairing the convex will weaken the strength of the valve barrel. The safety valve has a small flow rate and poor adaptability to the top plate.

In foreign countries, research and improvement on the three purpose valve for single hydraulic props have been relatively rapid. For example, the new generation of single hydraulic prop three way valves produced by German company Danmas have made significant improvements in both performance and structure. In October 1993, Danmas demonstrated its newly developed three way valve, which uses a new anti-corrosion material treatment process for its valve shell, stainless steel material for its valve core, valve seat, and spring, which has good anti-corrosion ability. Its structure adopts a large flow safety valve structure. The safety valve spring adopts a gas spring, which reduces the spring stiffness and improves the performance of the safety valve. The air chamber adopts an adjustable structure and has excellent performance. All of its seals adopt new polyurethane seals, greatly improving their service life. The performance parameters are shown in the table. Therefore, it is necessary to develop a new type of anti-corrosion and anti pollution three-way valve to improve the service life of single hydraulic props and three-way valves in China, and to enhance the anti-corrosion and anti pollution capabilities of the valve.
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