AB Series
Bi-directional Knife Gate – AB Series
Bidirectional wafer knife gate valve with a monobloc machined body and soft U-shaped seat, designed for process water and general services containing up to 4% suspended solids.
Bidirectional
DN50 – DN600*
Liquids up to 4% solids
Monobloc machined cast body
*Other nominal diameters and pressure ratings available on request.
Overview
The AB Series is a bidirectional wafer knife gate valve with a one-piece machined cast body and wedges on both sides. This design allows the valve to work with fluid in either direction at the same working pressure. The full, straight-through port provides high flow with low pressure drop, ideal for process water and light slurries.
A soft U-shaped rubber seat surrounds the gate perimeter. An internal stainless-steel wire maintains the joint shape and position, ensuring a flat, continuous sealing surface that prevents cavities and reduces solid build-up around the seat area.
Utilisation
- General industry process lines
- Chemical plants
- Pumping and transfer duties
- Food industry utilities
- Water treatment – clean and waste water
In all these applications, the valve should be installed once the fluid has been filtered to remove coarse solids and larger particles.
Technical Specifications
Sizes & Working Pressure
- Standard sizes: DN50 – DN600*
- DN50–DN150: 10 bar
- DN200: 8 bar
- DN250–DN300: 6 bar
- DN350–DN400: 5 bar
- DN450–DN600: 3 bar
Working pressures are valid in both directions. Higher ratings and larger diameters available on request.
Design & Connections
- Bidirectional wafer knife gate valve
- Monobloc machined cast body with double wedges
- Full port for high flow and low pressure loss
- Flange drilling: EN 1092 PN10, ASME Class 150 (others on request)
- Face-to-face dimensions according to CMO standard
Body, Gate & Seat
- Body: GJS-250 cast iron or CF8M stainless steel
- Optional: GJS-500 ductile iron, carbon steel, special stainless steels
- Gate: AISI 304 or AISI 316 stainless steel, polished edges
- Seat: U-shaped elastomer sealing joint with internal stainless-steel wire
- Seat materials: EPDM, NBR, FKM and others to suit the medium
Sealing & Packing
Soft seat fully supported in the body and in contact with the gate perimeter.
Flat seal design prevents solid accumulation and internal cavities around the seat area.
Packing sets selected according to medium and temperature (PTFE, graphite, synthetic fibres, etc.).
Optional bonnet design for zero-emission sealing to atmosphere on demanding services.
Actuation & Accessories
- Handwheel (rising or non-rising stem)
- Gearbox for low-effort operation on larger sizes
- Lever (small diameters)
- Pneumatic, electric or hydraulic actuators
- Limit switches, solenoid valves and control accessories
- Extensions, locking devices and stroke limiters
Applications in South Africa & Africa
The AB Series knife gate valve is a versatile general-purpose slurry and process valve for installations across South Africa and the African region where reliable bidirectional shut-off is required on lightly loaded liquids.
Water & Wastewater
Process and service water, filtered effluent and lightly loaded wastewater in municipal and industrial treatment plants.
Chemical & Industrial
Chemical plants, dams and hydrological projects, industrial utilities and general plant services compatible with the selected materials.
Food & Pulp and Paper
Food industry process and utility lines, plus pulp and paper stock lines with limited solids content after filtration.
AB Series Datasheet & Documentation
Download the official AB Series datasheet to view detailed dimensions, pressure ratings, material options and installation recommendations for design and project specifications.
REQUEST A QUOTE
Send your required size, pressure rating, medium, temperature and preferred body and seat materials. Our South Africa team will help you specify the right AB Series configuration for your plant or project.
Call our team
Email sales
sales@cmoafrica.co.za