The difference between valve and gate valve and selection

Gate valve opening and closing pieces is the gate, the direction of movement of the gate and fluid perpendicular to the gate valve can only be fully open and closed, unsuitable for regulation and throttling. The gate has two sealing surfaces. The two most commonly used wedge gate valves form a wedge on the two sealing faces. The wedge angle varies with the valve parameters, typically 5 °. Wedge gate valve gate can be made as a whole, called the rigid gate; can also be made to produce a small amount of deformation of the gate, to improve its technology to make up for sealing surface angle in the process of deviation, this gate The board is called a flexible gate. Gate valve is closed, the sealing surface can only rely on medium pressure to seal, that is, rely on media pressure to the sealing surface of the gate pressure to the other side of the valve seat to ensure that the sealing surface of the seal, which is self-sealing. Most of the gate valve is forced seal, that is, when the valve is closed, it must rely on external force to force the gate to the valve seat to ensure the sealing surface of the seal. Gate valve has the following advantages: 1. Fluid resistance is small, the sealing surface by the media erosion and erosion of small. 2. Opening and closing more effort. 3 medium flow unrestricted, no spoiler, does not reduce the pressure. 4. Simple shape, short structure length, good manufacturability and wide range of application. Nominal pressure or pressure level: PN1.0-16.0MPa, ANSI CLASS 150-300LB, JIS10-20K Nominal diameter or diameter: DN10 ~ 1000, NPS 1/2 ~ 36 "Connection: flange, butt welding, thread, etc. Applicable temperature: -196 ℃ ~ 700 ℃ Driving mode: manual, bevel gear, pneumatic, electric, hydraulic, gas-liquid linkage, electro-hydraulic linkage Valve body material: WCB, ZG1Cr18Ni9Ti, ZG1Cr18Ni12Mo2Ti, CF8 (304), CF3 ), CF8M (316), CF3M (316L), Ti. Choose different materials, can be applied to water, steam, oil, nitric acid, acetic acid, oxidizing media, urea and other media. (Valve) moves along the valve seat center line valve.According to the valve disc in this form of movement, valve seat opening changes in proportion with the valve stroke is proportional to the valve stem opening or closing stroke relative to Short and very reliable cut-off, and because valve seat openings vary in direct proportion to valve flap travel, making it ideal for regulating flow rates.Thus, this type of valve is ideally suited for shut-off or adjustment as well as section Flow use. The original selection Is: 1, high temperature, high pressure medium pipe or device should be used on the globe valve, such as thermal power plants, nuclear power plants, petrochemical systems of high temperature, high pressure pipeline .2, pipeline convection resistance requirements on the pipeline. Pressure loss is not considered a small place.3, small valve needle valve, instrument valve, sampling valve, pressure gauge valve, etc .. 4, flow adjustment or pressure adjustment, but less demanding on the adjustment accuracy, and the pipe diameter Relatively small, such as the nominal pass through the pipeline less than or equal to 50mm, should be selected .5, synthetic industrial production of small chemical fertilizers and large chemical fertilizer should use nominal pressure PN160 nominal pressure 16MPa or PN320 nominal pressure 32MPa high pressure angle type valve or high pressure angle Throttle valve .6, alumina Bayer process in the production of desiliconization workshop, easy to coking pipe, easy to choose the valve body separate, the valve seat can be used, the cemented carbide seal of the DC globe valve or DC Throttle .7, urban construction in the water supply, heating engineering, nominal pass through the smaller pipe, the choice of cut-off, balance valve or plunger valve, such as the nominal pass through less than 150mm of the pipeline. The most obvious Point is: in the opening and closing process, due to the valve disc sealing surface than the friction between the valve smaller than the wear-resistant. Open the height of the valve seat is usually only a quarter of the channel diameter, so much smaller than the gate valve Normally there is only one sealing surface on valve body and valve disc, so manufacturing technology is better and maintenance is easy. Nominal pressure or pressure level: PN1.0-16.0MPa, ANSI CLASS 150-900, JIS10-20K Nominal diameter or Diameter: DN10 ~ 500, NPS 1/2 ~ 36 "Connection method: Flange, butt welding, thread, etc. Applicable temperature: -196 ℃ ~ 700 ℃ Drive: Manual, bevel gear, pneumatic, electric, hydraulic, gas Hydraulic linkage, electro-hydraulic linkage Valve body material: WCB, ZG1Cr18Ni9Ti, ZG1Cr18Ni12Mo2Ti, CF8 (304), CF3 (304L), CF8M (316), CF3M (316L) Selection of different materials, can be applied to water, steam, oil, nitric acid, acetic acid, oxidizing media, urea and other media. More keyword search: cut-off valve, gate valve

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