News Center

News Center

One-stop Solution for Valve Products

**Knife Gate vs. Plug Gate vs. Sluice Gate: 9 Ways to Tell Them Apart**

Release time:

Nov 24,2025

Knife gate valves, Plug gate valves and sluice gates all fall under the category of shut-off valves, primarily used to isolate or connect the medium within pipelines. However, they exhibit significant differences in structure, operating principles and application scenarios. The following provides a detailed comparison:

  • Knife Gate Valve

（一）Structural Features

1、Gate plate: Thin and sharp, blade-shaped (resembling a knife edge), capable of cutting through media containing solid particles, fibres, or viscous substances (such as slurry, pulp, sewage).

2、Valve body: Typically straight-through design with unobstructed flow path, minimising pressure loss at full opening.

3、Sealing:

Soft seal: Utilises rubber or polyurethane seats, suitable for low-pressure, ambient-temperature applications.

Metal seal: Employed for high-temperature or abrasive media, though offering inferior sealing performance.

4、Actuation: Manual, pneumatic or electric (large diameters require gearbox assistance).

（二）Application Scenarios

1、Media: High viscosity, containing solid particles (e.g., sewage, ore slurry, pulp, sludge).

2、Industries: Wastewater treatment, mining, papermaking, chemical processing, food processing.

3、Pressure/Temperature: Low pressure (typically ≤ PN16), ambient temperature (soft seal ≤ 80°C).

（三）Advantages

1、Simple construction with minimal flow resistance, suitable for media with high solids content.

2、Thin gate plate provides strong shutoff capability and is less prone to sticking.

（四）Disadvantages

• Generally unsuitable for high pressure or high temperature applications; metal seals are prone to leakage.

  • Plug Valve

（一）Structural Features

1、Gate plate: Flat plate (not blade-shaped), inserted vertically or at an angle into the valve seat, sealed by pressure.

2、Valve body: Square or circular flange connection, commonly used in powder and granular material conveying systems.

3、Sealing:

Soft seal: Rubber or polyurethane, employed where high airtightness is required (e.g., dusty environments).

Hard seal: Metal-to-metal contact, offering wear resistance but inferior sealing performance.

4、Actuation: Manual, pneumatic, or hydraulic (large sizes require high-torque drives).

（二）Application Scenarios

1、Media: Dry powders, granules, bulk materials (e.g. cement, grain, pulverised coal, plastic pellets).

2、Industries: Cement, grain storage, chemical, metallurgical, pneumatic conveying systems.

3、Pressure/Temperature: Low pressure (≤PN10), temperature dependent on sealing material.

（三）Advantages

1、Suitable for powder material isolation, resistant to blockage.

2、Simple structure, easy maintenance.

（四）Disadvantages

1、Unsuitable for liquids or viscous media (prone to gate plate adhesion).

2、Poor sealing performance under high pressure differentials.

  • Sluice Gates

（一）Structural Characteristics

1、Gate plate: Heavy rectangular or circular slab, typically metallic (cast iron, stainless steel), sealed by self-weight or external force.

2、Valve body: No conventional valve structure; installed directly within channels, reservoirs, or pipelines.

3、Sealing: Metal-to-metal or rubber-lined, relying on external pressure (e.g., water pressure) for auxiliary sealing.

4、Actuation Methods: Manual screw, electric actuator, or hydraulic cylinder (for large gates).

（二）Application Scenarios

1、Medium: Water, sewage, liquids (free of solid particles).

2、Industries: Hydraulic engineering (waterways, reservoirs), municipal drainage, wastewater treatment plants.

3、Pressure/Temperature: Low pressure (relying on liquid column pressure), corrosion resistance sufficient.

（三）Advantages

1、Robust construction, suitable for large diameters (up to several metres wide).

2、High flow-interception capability, commonly used for flood control or flow regulation.

（四）Disadvantages

1、Bulky, slow opening/closing speed.

2、Unsuitable for media containing solids (prone to jamming).

keywords

Previous Page:

Analysis of the Differences and Applications Between Partial Lift and Full Lift Safety Valves

Golden Maintenance Period for Valves

:Next Page

Previous Page:

Analysis of the Differences and Applications Between Partial Lift and Full Lift Safety Valves

Next Page:

Golden Maintenance Period for Valves