- Gate valve
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- DIN f4 di flange resilient epdm gate valveDN450-1200 Resilient Seated Gate ValveDIN F5 Non-rising stem Resilient gate valveDIN F5 Socket connection soft seal gate valveUnderground cap soft seal gate valveBS5163 Rising stem Resilient soft seal gate valveBrass Threaded Gate ValveHard seal gate valveAPI Slab Gate ValveStainless Steel Gate ValveStainless Steel Knife Gate ValvePneumatic gate valve Control valveSoft Seal Gate ValveExtension stem gate valveNon rising stem Groove Soft Sealing Gate ValveRising stem Forged steel gate valveAPI carbon steel gate valveThreaded Gate ValveDin rising Stem And Non-Rising Stem Gate ValveUL-FM Rising stem flanged fire fighting system gate valveANSI Cast Iron Gate ValveBritish Standard Soft-Sealing Gate Valve
- Butterfly valve
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- DN2000 Double Eccentric Butterfly ValveFlange butterfly valveLug butterfly valveWafer Butterfly Valve With HandleWorm Gear Operated Wafer Butterfly ValveWafer lined fluorine butterfly valvestainless steel wafer butterfly valveStainless Steel Flanged Butterfly ValveEccentric soft sealing flange butterfly valveElectric three-eccentric metal hard seal butterfly valvePneumatic Flanged Butterfly ValvePneumatic Wafer Butterfly ValveThree eccentric metal seals wafer butterfly valveULC butterfly valve reportInflatable Butterfly ValveHigh Performance Butterfly ValveGrooved butterfly valvesElectric soft sealing wafer butterfly valveDouble flange fluorine lined butterfly valveHandle Aluminum Butterfly ValveWorm Gear Aluminum Butterfly ValveFull PTFE lined wafer butterfly valveOne stem no-pin wafer butterfly valveMulti standard Aluminum handle wafer butterfly valveMulti standard soft seat aluminum lever coated discwafer type butterfly valveResilient Seated Butterfly ValveMulti standard soft seat wafer type butterfly valveWafer PTFE seat butterfly valveWorm Gear Operated Lug Butterfly ValveStainless Steel wafer Butterfly ValvePneumatic Wafer Butterfly ValveWafer Type Metal Seat Butterfly ValveLug type manual wafer butterfly valve without pinAluminium Handle Lug Butterfly ValveWorm Gear Operated Flange Butterfly ValveLever Operated Flange Butterfly ValveButterfly valve stemButterfly valve discButterfly valve seat
- Ball valve
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- High platform flange ball valveCast Iron Ball ValveSS Thread Ball ValvesThree Piece Type Ball ValveAPI Ball ValveStainless Steel 3PC Ball ValvePTFE Seat Flanged Ball ValveForge Steel Fully Welded Ball ValveMetal Seat Ball Valvesfixed ball valveFlange connection ball valve3PC Type Ball Valve With Internal Thread Q11F/H-1000WOGThree Way Ball ValveANSI API Cast Steel And Stainless Steel Flange Ball valveTwo-PCS Type Thread Ball Valve
- Globe Valve
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- API Carbon Steel Globe ValveBellows Globe ValveStainless steel flange globe valveStainless steel thread S type globe valveStainless steel thread B type globe valveCast Steel Globe ValvePiston Globe ValveWCB Carbon Steel Globe Check Valveelectric motorized control stainless steel SS316 globe valveBrass Globe ValveCryogenic Globe valveHT200 Globe ValveThreaded Stainless Steel Globe ValveGG25 Globe ValveANSI API Cast Steel And Stainless Steel Globe valve
- Check valve
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- DN800 Slow Closing Check ValveDN800 Rubber Disc Check ValveButterfly Buffering Check Valvecheck valve with counter weightSilent Check ValveStainless Steel flange Check ValveSwing Check ValveSingle Chip Check Valve H74WStainless Steel Wafer Check ValveSwing Start Check ValveFoot check valveAPI Swing Check ValveWCB Swing Check ValveCheck ValveLifting Check ValveBottom ValveHammer Diminish Noises Check ValveWafer Check ValveDuctile Iron Check Valve
- Water Meter
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- Vertical Type Water MetersStainless steel threaded water meterPiston water meterPlastic water meterMore flow rotor dry water meterspiral vane flange water meterCI wotlman water meter with pulse outputLXCLG(R) Vertical removable element woltman cold (hot) water meterSingle flow rotor dry water meterPrepaid Token Water MeterElectromagnetic flowmeterRotary Piston Liquid Sealed Water MeterRotary Piston Liquid Sealed Water Meter
- Air valve
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- Double ball exhaust valveDoubleair Air Valve SaudiDoubleair Air Valve Southeast AsiaDoubleair Air Valve South AmericaDouble Air ValveThreaded Air ValveSingle Air ValveTriple Functions Air ValveAutomatic Air Release ValveAutomatic release valveAutomatic exhaust valveComposite Exhaust Air ValveBrass exhaust valveDouble Ball Air Valve
- Pipe Repair & Coupling
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- Flexible Multi-Function Pipe Coupling ZFJ-SSS Semi-Circle Pipe Repair Clamp SJW-HDuctile Iron Band Repair ClampStainless Steel Band Repair ClampDouble-Section Pipe Repair CouplingFolding Type Pipe RepairSingle-Section Multi-Function Pipe Coupling MF-SGear-Ring Type Multi-Function Pipe Coupling GR-SZBW Damping Corrugated Hose
- Dismantling Joint
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- VSSJAFC(CC2F) Detachable Flange Transmission JointVSSJA-2(B2F) Double Flange Limited Expansion JointVSSJA-1(BF) Single Flange Limited Expansion JointVSSJA(AF) Flange Loose Expansion JointJGD-B Threaded Rubber JointZBW Damping Corrugated HoseKXT-S Flexible Dual-Spherical Rubber JointKXT Rubber Soft JointFlange Adaptor
Advantages and disadvantages of gate valves
Overview of gate valves:
Gate valves are one of the most common types of valves in the isolation category. They can be found in every refinery, chemical plant, power station, and industrial production facility, and can be manufactured in sizes ranging from DN6 to 4200. gate valves are chosen for the primary purpose of fluid shutoff. It is for this reason that gate valves are often referred to as "cut-off" or "blocking" valves.
Gate valves are generally used in the fully open or fully closed operation. When fully open, the pressure drop through the gate valve is very small; when fully closed, the pressure sealing performance is very good. Due to the fit of the gate and seat ring, there is almost no leakage when the gate valve is closed. However, in the case of very low back pressure (generally not less than 0.34 bar, 1 bar = 105 Pa), some leakage may occur.
Another advantage of gate valves is that they usually open and close very slowly, a feature that prevents fluid water hammer effects from damaging the piping system.
The main limitation of gate valves is that they cannot be used in throttling conditions. When gate valves are used in dry throttling service, the fluid often has a high flow rate near the seat, which can cause erosion. Also in the partially open state, the gate will swing under the impact of the medium, which will cause damage to the seal. Usually, gate valves are more prone to seat and gate seal surface wear than globe valves, and the repair of such wear is difficult to be accomplished by means of grinding and polishing.
Because the structural characteristics of the gate valve are very suitable for large-scale devices, its application range is expanding, and to high temperature and high-pressure development. The maximum diameter of the gate valve has reached DN4200, in the ammonia plant has been a large number of high-pressure gate valve PN320, for oil and gas drilling wellhead gate valve working pressure up to 138MPa. manufacturing a high-temperature and high-pressure gate valve is the key to solving the problem of wedging the gate plate due to temperature changes, as well as ensuring its reliable sealing performance. To this end, the gate and seat sealing structure should be studied and improved. Resilient seats and resilient floating seats have begun to be applied to enable the gate valve to achieve inlet sealing, outlet sealing, or double sealing of import and export.
Composition of gate valve:
Gate valve, also called the gate valve, mainly consists of the valve body, bonnet, gate, stem, seat and seal packing, and other parts.
The gate valve is the opening and closing member (gate), driven by the valve stem, along the seat (sealing surface) to do a linear movement of the valve. Generally, the gate valve can not be used to regulate the flow, only a cut-off device can be used, either completely open or completely closed. Among the various types of valves, the gate valve is the most widely used one. It is suitable for both normal temperature and pressure conditions, as well as high and low temperature and high and low-pressure conditions, and can be applied to a variety of different media through the selection of different materials.
The advantages of the gate valve:
①Small fluid resistance. Gate valve body's internal media channel is straight, the media flow through the gate valve does not change its flow direction, so the fluid resistance is small.
② structure length (the distance between the two ends connected to the pipe) is small. As the gate is disc-shaped, is placed vertically in the body of the valve, and the globe valve flap (also disc-shaped) is placed parallel to the body of the valve, so compared with the globe valve, its structure length is smaller. Such as the PN16, and DN150 globe valve, the structure length of 480mm, while the same parameters of the gate valve structure length are only 350mm.
③ opening and closing less effort. When opening and closing the gate movement direction is perpendicular to the direction of media flow, while the shut-off valve flap is usually closed in the direction of movement and seated in the opposite direction of media flow, and therefore must overcome the force of the medium. Therefore, compared with the shut-off valve, the opening, and closing of the exposition valve is more labor-saving.
④ Media flow direction is not restricted. The medium can flow from both sides of the gate valve in any direction through the gate valve and can achieve the purpose of connection or cut off. Easy to install, suitable for the flow direction of the medium may change in the pipeline.
⑤ When fully open, the sealing surface is subject to minimal erosion of the working medium.
⑥The structure of the body is relatively simple, and the manufacturing process is good.
Disadvantages of the gate valve:
①Sealing surface is easy to produce abrasions. When opening and closing the gate and the valve seat in contact with the relative sliding between the two sealing surfaces, under the action of the medium thrust easy to produce abrasion, thus destroying the sealing performance, and affecting the service life.
② more parts, the structure is more complex, manufacturing and maintenance are more difficult, compared with the cost of the globe valve are higher.
③ shape size and opening height are larger, and the space required for installation is larger.
④Generally gate valves have two sealing pairs, which adds some difficulties to processing, grinding, and maintenance.
⑤ The operating stroke is large, and the opening and closing time is long. Since the gate needs to be completely lifted to the top of the seat channel when opening, and all the gate needs to fall down to block the seat channel when closing, so the opening and closing stroke of the gate is large, and the opening and closing time is long.