The name of piston-ring valves is derived from the design characteristics of the valves themselves. Piston-ring valves are mainly used in systems where large pressure differences and high flows occur.
Their application is mainly in water supply systems, power plants, industrial and process technology and other branches of economic activity.
According to a large number of design variants, piston-ring valves have multiple roles in pipe systems and are used as shut-off devices, measuring devices, pressure and flow regulators, safety devices, safety devices with check valve functions, and valves with drain and flush outlets.
The flow cross-section of the piston-ring valves is in the shape of a ring, and the moving part through which the regulation is realized is in the shape of a piston. The outer housing is formed in such a way that the cross-sectional flow from the entrance to the annular seat is continuously reduced.
The valve piston inside the housing has two annular guides and can be moved in the axial direction via a curving mechanism. Complete closing of the valve is achieved by resting the piston sealing ring on the annular seat of the valve. The annular seat is detachable from the housing and changing the type of annular seat allows you to change the hydraulic characteristics of the piston-ring valve without changing the pipeline. Depending on the function and conditions in which the piston-ring valves will be used, different types of ring seats are used.
Connection dimensions are according to SRPS M.B6.011 and DIN 2501, nominal pressures 10, 16, 25 and 40 (bar), and nominal diameters from DN 150 to DN 1200 (mm).
The housing, piston and curving mechanism of the piston-ring valves are made of structural steel by welding, provided that the sealing surfaces are made of appropriate stainless steel, and the sealing rubber is made of EPDM. The shaft of the piston-ring valves is made of stainless steel, and the plain bearings are made of special grey cast iron.
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