GL Valves
Slurry Knife Gate Valve – GL Series
Bidirectional wafer-type slurry knife gate valve with a monoblock cast body and twin rubber sleeves, engineered for highly abrasive mining and industrial slurries while maintaining full-bore, low-turbulence flow.
Bidirectional
DN50 – DN1500*
Heavy-duty slurry service
Two rubber sleeves
*Additional diameters and custom configurations available on request.
Overview
The GL Series is a bidirectional slurry knife gate valve with a one-piece “monoblock” cast body and stainless-steel gate. Two robust rubber sleeves form a push-through seat, enclosing the flow path so that the medium only contacts the sleeves and gate. The result is a full, continuous bore that minimises turbulence and pressure loss, even with dense slurries.
This design is ideal for African mining and process plants where reliability, high solids loading and abrasive conditions are part of everyday operation. The valve is equally suited to chemical and wastewater duties where a tight, bidirectional shut-off is required.
Key Features
- Bidirectional shut-off with equal pressure rating in both directions.
- Monoblock cast body to resist bending and vibration in slurry pipelines.
- Full bore, short pattern design for high flow and compact installation.
- Replaceable sleeves that protect the body from abrasion.
- Various elastomers available to match the process medium and temperature.
Technical Specifications
Sizes & Working Pressure
- Nominal sizes: DN50 – DN1500*
- DN50 – DN150: up to 16 bar
- DN200 – DN600: up to 10 bar
- DN700 – DN900: up to 8 bar
- DN1000 – DN1200: up to 6 bar
Working pressures apply in both flow directions. Higher ratings or larger sizes on request.
Design & Connections
- Bidirectional wafer / semi-lug slurry knife gate valve.
- Short-pattern monoblock body for compact face-to-face.
- Full port for high flow with low pressure drop.
- Standard flange drilling: EN 1092 PN10 and ASME Class 150.
- Other drilling standards (PN6, PN16, PN25, JIS, British, Australian) available on request.
Body, Gate & Sleeves
- Body: GJS-500 cast iron or CF8M stainless steel as standard.
- Optional bodies: carbon steel and special stainless alloys for aggressive media.
- Gate: AISI 304 or AISI 316 stainless steel, with smooth edges to protect the sleeves.
- Seat: two opposing rubber sleeves forming a push-through seal.
- Sleeve materials: natural rubber, EPDM, nitrile, polyurethane and other elastomers.
Sleeve & Sealing Design
- Each sleeve incorporates an internal metal ring to maintain roundness under compression.
- When the valve is open, the sleeves stay in contact, preventing pockets where solids could collect.
- When the gate closes, it pushes cleanly through the sleeves to create a tight, bubble-tight seal.
- No metal body surfaces are exposed to the slurry, extending valve life in abrasive services.
- Sleeves can be replaced without removing the valve body from the line (depending on size and layout).
Actuation & Accessories
- Manual handwheel (rising or non-rising stem).
- Gearbox operation for larger diameters.
- Pneumatic, hydraulic or electric actuators.
- Limit switches, solenoid valves and position indication.
- Supports, stem extensions and locking devices as required.
Applications in South Africa & Africa
The GL Series slurry knife gate valve is developed specifically for demanding mining and process applications found across South Africa and the African continent. Its full-bore, sleeve-lined design makes it well suited to high-solids, high-wear duties where uptime matters.
Mining & Slurry Pipelines
Transport of ore slurry, tailings, cyclone feed, mill discharge and thickener underflow on gold, platinum, coal, base metal and mineral sands operations.
Chemical & Energy
Abrasive and corrosive fluids in chemical plants, thermal power stations and energy projects where reliable isolation and full flow are required.
Water & Wastewater
Loaded wastewater, sludge and process effluent in municipal and industrial treatment plants, including return lines and recycle streams.
GL Series Datasheet & Documentation
Download the official GL Series datasheet for detailed dimensions, materials, pressure ratings and installation recommendations for your next project specification.
REQUEST A QUOTE
Share your pipeline size, pressure, slurry type, solids concentration, temperature and preferred materials. Our South African team will help you specify the correct GL Series configuration for your mining, energy or industrial plant in Africa.
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sales@cmoafrica.co.za