ChinaGateValveSuppliers Carbon steel gate valve suitable for industrial, process, offshore and petrochemical use. Manually operated, supplied with a handwheel (gearbox). carbon steel bolted bonnet gate valve is suited for process, off shore and petro-chemical industry use. They are robustly constructed having a flexible wedge which gives a positive shut off even when the pipework in which the valve is fitted, is stressed. These valves are usually flanged to ANSI B16.5 standards but can also be supplied to BS4504 BS10 standards Features, Benefits Approvals 鈼?Outside screw yoke 鈥?Rising stem with flexible wedge 鈼?Handwheel operated as standard 鈼?Gearbox actuator options available - Carbon Steel Gate Valve Trim 8 ANSI Class 150 / 300 /600 RF - Also known as Cast Steel, WCB, CS Gate Valve. - Standard Graphite Packing. - Other gasket material can be made available. - Design and Manufacture according to API 600 or API 602. - Face-to-Face dimensions according to ASME B16.10 - 2009. - End Flange Dimension according to ASME B16.5 - 2009. - Inspection and Test according to API 598 - 2009. Technical Data Design StandardAPI600, API6D, DIN3352, EN10434 Body MaterialWCB, LCB, LCC, WC6, WC9 NACE MR-01-75/NACE MR-01-03 Special Requirements Pressures rangeANSI 150 ~ANSI 2500 ,PN10~PN420 Size rangeDN50(2") ~DN1200 (48") Face to FaceANSI1B 16.10 ,EN 558,DIN3202 Flanged RF, FF, RTJ EndsASME B16.5 鈮?DN600 (24") ASME B16.47 A 鈮?DN650 (26") BS 4504,DIN 2543-2545,EN1092 Butt-Weld BW EndsASME B16.25 ,DIN 3239,BS 2080, EN 12627 Temperature range-29掳~ 425掳C Design Feature ConstructionPressure seal锛孊olted Bonnet, Welded bonnet Wedge Typeflexible wedge, solid wedge, double wedge etc Stem DesignRising stem,Non-rising stem Seat SealingIntegral body seat ,seat welded and overlaid Valve OperationBevel gear, handwheel, bare shaft By passes,locking devices,extended stem,etc Fire Safe DesignAPI 607,BS 6755 Inspection and Test Visual InspectionMSS SP-55 Material InspectionPMI Test----Chemical Analysis HB Test---Hardness Test UT---Ultrasonic Test RT---RadiographicTest MT---Magnetic Test NDT Test Non-destructive Dimention inspcetionAccording to drawings Valve Inspection and TestAPI 598,DIN 3230,EN 12266,BS 5146 Summary of gate valve A gate valve is designed for a fully open and or a fully closed service. They act as an isolating valve since its only function is either to stop or to let the flow go through. It allows minimal dirt from entering the pipe. Gate valves have 2 main parts which are parallel and wedge-shaped. For the parallel shape, it鈥檚 a flat gate valve with 2 parallel seats that has a sharp edge at the bottom. The wedge shape valve has 2 inclined seats but the gate tends to mismatched. There are 3 types of gate valves: the solid taper wedge, the flexible wedge, and the split wedge or parallel disk valve. A solid tape wedge is the most common. Due to its simplicity and strength, it can be installed in any position. It's good for all types of fluid, but this type of design does have some leakage. A flexible wedge is a one piece solid disk with a cut around the perimeter, which is good for thermal binding. It has better seat alignment which helps prevent leaks and are mostly used in steam systems. A split wedge has 2 discs and holds together with a special mechanism which allows a disc that's out of alignment to adjust back into place while the other disc holds up everything. The parallel disk have 2 discs that are spring loaded.They are mostly used in non-condensing gasses and liquids at normal and high temperatures without the valve being affected. How to Use a Gate Valve Gate valve operation is simple, only requiring the user to turn the handwheel in the correct direction to open or close the valve as necessary. Closing or opening a gate valve involves rotating the wheel through 360 degrees in the required direction - this, in turn, rotates the threaded valve stem, and thus raises or lowers the attached gate disk. How to Tell If a Gate Valve is Open or Closed Unlike with certain other flow valve types, it is not always easy to tell whether a gate valve is open or not. Ball valves and butterfly valves, for example, will usually be closed when the handle is perpendicular to the pipeline or flow direction. Since gate valve wheels sit above or to the side of the pipe and rotate through 360 degrees to open and close, you cannot always tell which position they are in at a glance. In most cases, turning a gate valve anticlockwise will open it, while turning it clockwise will close it. These directions will normally be marked on the handwheel or elsewhere on the outer body of the valve. Unless you know for a fact that a gate valve is jammed or bound, you should always stop turning them when you start to feel significant resistance. Continuing to turn a gate valve against resistance can damage it, or the plumbing or ducting it is installed on. It may therefore be necessary to try turning a gate valve in either direction to ascertain which position it is currently in. What are Gate Valves Used for? Most types of gate valve can be thought of simply as a sluice valve or control valve for water supply. Gate valves are used for starting or stopping the flow of liquid (or steam/gas) through a section of pipeline, allowing that section to be completely shut off and isolated when necessary. They are among the most common sorts of valves and taps you will find in most pipeline applications, and are used in a wide range of industrial settings. These might typically include: 鈼?Oil and gas extraction 鈼?Processing plants and water treatment facilities 鈼?Various types of factories and production environments 鈼?Medical and laboratory uses 鈼?Food production and catering 鈼?Automotive and mechanical 鈼?Marine and offshore uses 鈼?Seawater desalination treatment Certain types of gate valves are often suitable choices for both high pressure and high temperature applications. Although quite a simple sort of valve in principle, they are highly effective when used in the right circumstances. Being fire-safe also means they are a suitable choice for high pressure-temperature scenarios. Unlike some other types of shutoff valves (such as globe valves), a gate valve is only intended to be used in its fully open or fully closed state. Leaving it in a partially raised or lowered position will not have much effect on controlling the flow rate of the medium in the pipe, and may risk moving or damaging the valve due to excessive vibration. Gate valve are characterized by a 鈥済ate鈥?that closes in a plane perpendicualar to the flow of fluid. They are used primarily for on/off, nonthrottling service. Shearing of high-velocity flow will cause a partially open disk to vibrate and chatter, which will damage the seating surfaces and prevent a tight seal. They are suitable for most fluids including steam, water, oil, air, and gas. Gate valves may have either a solid or flexible wedge disk. In addition to on/off service, gate valves can be used for regulating flow, usually in sizes 6 in. and larger, but will chatter unless the disk is fully guided throughout travel. Gate valves respond slowly, requiring numerous turns of the handwheel, to go from fully open to fully closed. The disks are made in either a solid or flexible wedge disk. Flexible disks were developed to overcome sticking on cooling in high-temperature service and minimize operating torque. High-pressure service of large sizes is usually cheaper than plug or ball. Gate valves are more commonly used in refineries and petrochemical plants where pressure remains relatively low, but temperature may be very high. Gate valves are used less in upstream oil and gas production facilities due to high operating pressures, long opening/closing times, and severe environmental conditions when operating in marine atmospheres. The gate valve is a block valve. Due to its design, it cannot control flow; even at the beginning of opening, erosion of the seat and disk occurs, resulting in the destruction of the tight faces.ChinaGateValveSuppliers website:http://www.highmpavalve.com/gate-valve/