Carbon Steel Knife Gate Valves, DN700, PN10, Pneumatic, RF

Product Name: Carbon Steel Knife Gate Valves
Type: Unidirectional Knife Gate Valve
Body Material: Carbon Steel
Nominal Size: DN700, 700 mm, 28 Inch
Nominal Pressure: PN10
End Connection: RF Flanged
Operation: Pneumatic Actuator
Temperature Range: -29°C to 150°C
Medium: Used for pulp, coal ash, sewage, food, etc

Unidirectional knife gate valves are designed so that the gate plate always faces the flow direction of the medium. This means the valve allows flow in only one direction. Therefore, correct installation is essential, and special attention must be paid to the flow direction. An arrow is typically marked on the valve body to clearly indicate the required flow direction. While this design limits installation flexibility, it simplifies the sealing structure and reduces overall valve complexity.

Unidirectional knife gate valves use a wedge block mechanism to press the gate plate against the sealing ring, thereby achieving effective shut-off. The sealing ring is typically made of materials such as rubber, PTFE, or metal. It is installed within a stepped groove in the valve body and secured by a metal retaining ring. During valve opening and closing, the sealing ring maintains close contact with the gate to ensure sealing integrity and prevent leakage.

Technical Specification

» Structure: Unidirectional wafer knife edge gate valve

» Nominal Diameter: NPS 2-24 Inch (DN50-DN600)

» Design Pressure: PN10, PN16, Class 150 LB

» Temperature Range: -29°C to 538°C

» Max Working Pressure:

  DN50-DN250: 10 bar

  DN300-DN450: 7 bar

  DN500-DN600: 4 bar

» Body Material: Carbon Steel, Stainless Steel, Special Alloy, etc.

» Disc Material: Stainless Steel Chrome Plated, Special Alloy, etc.

» Seat Material: Stainless Steel + STL, EPDM (120°C), Viton (200°C), PTFE (200°C), NBR (80°C)

» Flange Standard: GB/T 9113.1, JB/T 79.1, HG 20592, ASME B16.5, EN 1092-1

» Face to Face: MSS SP-81

» Medium: Pulp, Coal Ash, Sewage, Food, etc.

» Applications: Pulp & Paper, Water Treatment, Beverage & Food, Fine Chemicals, Power Plants, Steel Industry, etc.

Product Features

» Cast-in guide claws at the port bottom secure the gate without a groove, preventing shutoff clogging and ensuring a tight seal. These claws push the gate toward the seat for optimal sealing in the closed position.

» Integral body design allows easy assembly and ensures zero shell leakage.

» Full-port configuration minimizes pressure drop and maximizes flow capacity.

» PTFE resilient points on the gate prevent metal-to-metal contact between the gate and body.

» Slim body and compact construction for easy installation.

» Beveled knife edge delivers strong cutting force and tight sealing.

» Optional increased gate thickness for higher pressure applications.

» Replaceable side-entry seat reduces maintenance costs.

» L-shaped seat retainer locks the seat into the valve body and shields the seat side from direct flow impact.

» Optional stem cover extends stem service life.

» Dual thrust bearings minimize operating torque.

» Grease nipple for easy bearing lubrication.