JIS Gate Valve

JIS Gate Valve

Gate valves made to the specifications and standards from JIS - the Japanese Standards Association are called JIS gate valves. JIS gate valves are made up of body, disc, stem, inner parts, seal, packing and gasket. The material for body and disc is WCB, ZG1Cr18Ni9Ti, CF8 (304), CF3 (304L), ZG1Cr18Ni12Mo2Ti, CF8M (316). As for the material for stem and inner parts, they are 2Cr13, 1Cr18Ni9Ti, 0Cr19Ni9 (304), 00Cr19Ni11 (304L), 1Cr18Ni12Mo2Ti, 0Cr17Ni12Mo2 (316). Seal surface uses the material named Cr13 or cemented carbides. Or sometimes it will use the same as body material. Flexible graphite material is used for the packing. The gasket is a stainless steel spiral wounded gasket. JIS gate valves are widely used in petroleum, chemical engineering, pharmacy and power stations.

With nominal pressure of 2~63K and temperature under -110~600℃, JIS gate valves have the main design features: firstly, they have reasonable construction, reliable sealing, excellent performance and nice appearance. Secondly, they own sealing overlaid with Co kentanium, which is resistant in abrasion, corrosion friction and can be used for a long time. thirdly, Stems of JIS gate valves are hared ,tempered and nitrogen treatment. They get functions of corrosion resistant and fraction resistant. Fourthly, the dual seals makes sure the performance is more reliable. Last but not least, spare material, flange and Bw ends dimensions/sizes are available according to actual conditions or customer’s requirements. As for the nominal diameters of JIS gate valves, they are DN50-DN800. JIS gate valves can be driven by manual/electric/conical gear/pneumatic, etc.

As for the working principle, JIS gate valves have the same principle as valve gate, because it is a kind of gate valves. On opening the JIS gate valve, the flow path is enlarged in a highly nonlinear manner with respect to percent of opening. This means that flow rate does not change evenly with stem travel. Also, a partially open gate disk tends to vibrate from the fluid flow. Most of the flow change occurs near shutoff with a relatively high fluid velocity causing disk and seat wear and eventual leakage if used to regulate flow. When fully open, the typical gate valve has no obstruction in the flow path, resulting in very low friction loss.