Gate Valve Manufacturer in USA for Full-Flow Isolation

Gate valves are linear-motion isolation valves designed to provide a substantially unobstructed flow path when fully open. The closure element moves vertically into or out of the flow passage, making the design suitable for applications where low pressure drop and full-line isolation are important.

SVR Global is a gate valve manufacturer in USA producing gate valves for oil and gas, petrochemical, refinery, power, water, wastewater, mining and general industrial applications.

What is the main purpose of a gate valve?

A gate valve is normally used in the fully open or fully closed position. It is not generally selected for prolonged throttling because partial opening can expose the wedge and seating surfaces to high-velocity flow, vibration, erosion and unstable operation.

When fully open, the closure element is withdrawn from the flow path. This provides a relatively straight passage and low pressure loss compared with many throttling-valve designs.

Common gate valve designs

Industrial gate valves include:

  • Solid wedge gate valves
  • Flexible wedge gate valves
  • Split wedge gate valves
  • Parallel-slide gate valves
  • Slab gate valves
  • Expanding gate valves
  • Through-conduit gate valves
  • Knife gate valves
  • Pressure-seal gate valves
  • Forged steel gate valves

Flexible wedge designs can accommodate limited seat misalignment caused by pipeline loads and temperature changes. Parallel-slide designs use two parallel closure surfaces and are commonly used in steam and power applications. Slab and expanding gate valves are frequently selected for pipeline service where full-bore flow and pigging may be required.

Valve manufacturers’ official product catalogues describe flexible wedge, split wedge, slab gate and double-disc configurations for services ranging from general process isolation to severe thermal and high-pressure duties.

API 600 and API 6D gate valves

API 600 is commonly applied to bolted-bonnet steel gate valves used in petroleum and related industries. API 6D covers pipeline valves and includes requirements relevant to slab and expanding gate designs.

Additional standards may include ASME B16.34 for pressure-temperature ratings, ASME B16.10 for face-to-face dimensions, ASME B16.5 for flanges and API 598 for inspection and testing.

Forged steel gate valves for smaller sizes and higher pressures are commonly designed around API 602. Pressure-seal bonnet construction may be used in high-pressure and high-temperature services because internal pressure assists the bonnet sealing arrangement.

Construction materials and trim

Common gate valve body materials include ASTM A216 WCB carbon steel, ASTM A217 alloy steels, ASTM A351 stainless steels, ASTM A352 low-temperature steels and ASTM A105 forged carbon steel.

Seat rings and wedge surfaces may use 13% chromium stainless steel, hard-facing alloys or other project-specific trim combinations. Graphite packing and gaskets may be specified for elevated temperatures, while low-emission packing arrangements can be required where fugitive-emission control is important.

Rising stem and non-rising stem

An outside screw and yoke rising-stem design allows the operator to see whether the valve is open or closed. The stem threads are positioned outside the pressure boundary and away from direct contact with the line medium.

Non-rising stem construction can reduce the required installation height and is commonly associated with waterworks and underground service. The selection depends on available space, maintenance access, environment and application.

Operation and testing

Gate valves may be operated by handwheel, bevel gearbox, electric actuator, pneumatic actuator or hydraulic actuator. Large sizes and high differential pressures can require substantial operating torque or thrust.

Manufacturers should calculate actuator or gearbox requirements from the valve design and maximum service conditions rather than relying only on nominal valve size.

Testing commonly includes hydrostatic shell testing and high- or low-pressure seat testing. Additional fire-safe, fugitive-emission, cryogenic, sour-service or non-destructive testing may be specified by the project.

SVR Global manufactures gate valves in different body materials, trim arrangements, pressure classes and end connections. By reviewing flow medium, differential pressure, temperature, orientation and operating frequency, a gate valve manufacturer in USA can recommend a design that provides dependable isolation with low flow resistance.
https://www.svrglobal.net/product-category/gate-valve/