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Egmec Industry Co., Ltd.
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Hydraulic Cartridge Valves
1. The application of frame-shift speed based on analysis of low-yield mechanized mining has become a constraint is an important factor. To speed up the frame-shift speed, the stent system used hydraulic cartridge valve. Plug-in direction of the valve solenoid valve is used as a pilot valve, main valve (poppet valve) for pilot control, control theory is equivalent to electro-hydraulic control valve, but the cartridge valve flow capacity (up to 10000L/min above) large , fast response, reliable operation and other advantages, is unparalleled tubular valve to make it more suitable for stent use electro-hydraulic control system, without the use of electromagnetic pilot developed a special high flow main control valve, both meet the requirements, but also improve work performance, increase the degree of generalization, a fundamental solution to the inherent deficiencies by the tubular valve problems arising. In addition, the use of hydraulic cartridge valve designed bracket system also has the following advantages:
a) The advantages of hydraulic cartridge valves are very suitable for stent condition. Hydraulic support condition is characterized by: medium low viscosity, high working pressure, flow, poor working conditions, media, pollution. Cartridge strengths can be fully realized.
b) Comply with the fluid power technology trends. To reduce the cost, to eliminate environmental pollution, use of fluid power technology is toward the direction of water media. Hydraulic support is closer to nature with the same high-water water-based emulsion as the working medium is likely to become beneficiaries of the technology development results, tend to use pure water is the working medium.
As the low viscosity of water, requiring the valve sealing to improve the efficiency of the system, The hydraulic cartridge valves with sealing cone, with excellent sealing performance, but also for work in water media, should be preferred as the water valve bracket types.
c) Anti-pollution ability, reliable work. Stents work in the coal face, medium pollution level is high, the spool of serious wear and tear, shortening the life of the valve, which also led to a variety of stent failure, the work reduced reliability, increased maintenance time, reducing the work surface productivity. Cartridge valve spool and suites with no strict requirements, wear light, easy to plug, it does not produce the phenomenon of hydraulic clamping, even when the dirty in the medium bracket hydraulic system to ensure normal and reliable work.
d) To meet the needs of some special conditions, strong pressure for the cycle as the hard and difficult to take off the roof of the support bracket, to a sudden pressure in the roof, the columns under the control valve in the valve chamber, through the large instantaneous flow, ordinary safety valve pass flow through the flow capacity can not meet the requirements, which designed the inflatable high flow valve, to adapt to this condition.
But this kind of valve complex, difficult to manufacture, assembly, demanding work and poor reliability, it is difficult to meet the requirements. Moreover, the column of the inferior vena safety valve should be installed to meet the ordinary needs of normal operating conditions, which will undoubtedly increase the number of components and manufacturing costs. The use of cartridge-type relief valve, is able to easily solve this problem, will make the system simpler.
