When completed and operating, Qatargas' four new LNG liquefaction and mega trains, at Ras Laffan, are expected to create the world's largest capacity for LNG, each delivering at an annual rate of 7.8 million tons. The Sustainable Manufacturing Summit Europe will bring together top global manufacturers to discuss carbon reduction and climate impact strategies. Circle Oil Plc, the international oil and gas exploration and Development Company, is pleased to announce that the exploration well ONZ6 has been drilled, logged and successfully tested in the Ouled N'Zala Permit, Morocco. # Plastic pressure pipe systems are used for the conveyance of drinking water, waste water, chemicals, heating and cooling fluids # Industrial valves, historically, contributed to environmental pollution and resource waist due to fugitive emissions # Valve Fire Safe Design and Validation # Cryogenic Valve can be cryogenic inspected and tested in accordance with BS 6364 to certify sealing performance in cryogenic conditions # Triple Offset Butterfly Valve Made in China ,which are designed in accordance with API 609, featuring a blow-out proof stem with a visible position indicator # High Temperature & High Pressure Power Valves A brief introduction # Fugitive Emission Control for valve manufacturer # Through conduit gate valves for oil & gas pipeline service # China API Pressure Seal Valve Feature and Application # About Conventional Gate Globe Check Valve Feature and Application
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What is gate valve
    A Gate Valve, or Sluice Valve, as it is sometimes known, is a valve that opens by lifting a round or rectangular gate/wedge out of the path of the fluid. The distinct feature of a gate valve is the sealing surfaces between the gate and seats are planar. The gate faces can form a wedge shape or they can be parallel. Gate valves are sometimes used for regulating flow, but many are not suited for that purpose, having been designed to be fully opened or closed. When fully open, the typical gate valve has no obstruction in the flow path, resulting in very low friction loss. Gate valves are characterised as having either a rising or a nonrising stem. Rising stems provide a visual indication of valve position. Nonrising stems are used where vertical space is limited or underground. Bonnets provide leakproof closure for the valve body. Gate valves may have a screw-in, union, or bolted bonnet. Screw-in bonnet is the simplest, offering a durable, pressure-tight seal. Union bonnet is suitable for applications requiring frequent inspection and cleaning. It also gives the body added strength. Bolted bonnet is used for larger valves and higher pressure applications. Another type of bonnet construction in a gate valve is pressure seal bonnet. This construction is adopted for valves for high pressure service, typically in excess of 15 MPa (2250 psi). The unique feature about the pressure seal bonnet is that the body - bonnet joints seals improves as the internal pressure in the valve increases, compared to other constructions where the increase in internal pressure tends to create leaks in the body-bonnet joint. Gate valves normally have flanged ends which are drilled according to pipeline compatible flange dimensional standards. Gate valves are typically constructed from cast iron, ductile iron, cast carbon steel, gun metal, stainless steel, alloy steels, and forged steels.
How to install Gate Valve
    Always follow standard safety procedures when working on a valve. The valve should be welded onto the line with the wedge in the fully closed position. Leaving the valve even partially open can cause distortion and leaking. Verify the drawings to make sure that the valve has bi-directional sealing capability. If the valve only has unidirectional sealing capability, make sure it is installed into the pipeline in the correct orientation. Single direction sealing gate valves have a nameplate on the side of the valve that has a relief hole or pressure equalizer. This should be the high pressure side when the valve is closed.
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