Knife gate valves
Seven knife gate designs, cast in stainless from 2 in and fabricated to 120 in. Metal, resilient and polymer seats. Uni-directional, bi-directional and double block and bleed. Ratings from 150 psi to 600 psi.
A full port, metal seated knife gate for one-way isolation. The heavy cast body and machined gate shear through solids and seat cleanly. Add a backing ring for reverse flow or horizontal mounting, or an elastomer O-ring seat for tighter shutoff.
- Body, gland, yoke
- Cast CF8 (304) stainless
- Gate
- ASTM A240 304, machined, beveled, surface ground
- Sizes
- Cast through 24 in, fabricated above 24 in
- Rating
- 150 psi CWP (10.3 bar)
- Optional O-ring seats
- Buna-N, EPDM, UHMWPE, FKM
- Standards
- MSS SP-81, ASME B16.5
A rubber seated knife gate with a perimeter seal, so it shuts off in either flow direction. A strong fit for water, wastewater and pump station isolation where flow can reverse.
- Body
- Cast CF8 (304) stainless
- Seat
- Buna-N standard, to 180 °F
- Seat options
- EPDM 300 °F, FKM 400 °F, PTFE 500 °F
- Sizes
- Cast through 24 in, fabricated above 24 in
- Rating
- 150 psi CWP (10.3 bar)
- Standards
- MSS SP-81, ASME B16.5
Two replaceable polymer seals give drip-tight shutoff both ways. The 316 stainless body suits corrosive and chemical service. Seals replace without replacing the valve.
- Body and gland
- Cast CF8M (316) stainless
- Seals
- Dual replaceable, PTFE standard
- Sizes
- Confirm size range
- Rating
- 150 psi CWP (10.3 bar)
- Standards
- MSS SP-81, ASME B16.5
Three replaceable polymer liners and a T-shaped seat insert that locks into them keep the media off the body. Built for abrasive slurry, tailings and sludge, where the wear parts should wear and the body should not.
- Body, gland, yoke
- Fabricated ASTM A36 carbon steel
- Gate
- ASTM A240 304, machined, surface ground
- Liners
- UHMWPE standard, to 180 °F
- Liner options
- Polyurethane, polypropylene, high temp UHMWPE, PTFE
- Sizes
- 2 to 48 in (DN50 to DN1200)
- Rating
- 150 psi CWP (10.3 bar)
A bonneted knife gate that contains the packing and keeps media off the stem. Choose metal-to-metal, metal with O-ring, or dual polymer seats.
- Body
- Cast CF8 (304) or CF8M (316)
- Sizes
- Cast 2 to 36 in, fabricated 42 in and up
- Seat options
- Metal, metal with O-ring, dual polymer
- Shutoff
- Uni-directional, backing ring for reverse flow
- Rating
- 150 psi CWP (10.3 bar)
- Standards
- MSS SP-81, ASME B16.5
The FIG 145 design built for higher pressure. Use it for slurry pipelines, pumped tailings and any lined service above 150 psi. Higher ratings are available on request.
- Body
- Fabricated ASTM A36 carbon steel
- Liners
- UHMWPE standard, T-shaped seat insert
- Sizes
- 2 to 48 in (DN50 to DN1200)
- Rating
- 300 psi CWP (20.7 bar), higher on request
- Standards
- MSS SP-81, ASME B16.5
Two polymer lined gates in one body with a drain and plug between them. It works as a double block and bleed valve and as a line blind, for maintenance isolation where people work downstream. Offered in FIG 145-UHMW, 40-MM and 50-PS configurations.
- Body
- Fabricated ASTM A36 carbon steel
- Seats
- Dual T-shaped inserts locked to polymer liners
- Sizes
- Up to 48 in
- Rating
- 150 psi CWP, higher available
- Standards
- MSS SP-61, ASME B16.5
When the line is too big, too hot, too abrasive or too high pressure for a catalog valve, we fabricate one. Past builds include a 72 in metal seated gate for an industrial facility in Texas and an all-titanium 8 in metal seated gate.
- Sizes
- To 120 in (DN3000)
- Rating
- To 600 psi (41.4 bar)
- Alloys
- 304, 316, 317L, duplex 2205 and 2507, 904L, Hastelloy, titanium
Options that come up on real jobs
Available across the line. Operators mount without welding, so you can change actuation later.
Operation
- Handwheel, with ball bearing yoke bushing on 14 in and larger
- 3:1 and 4:1 bevel gear, chainwheel, lever
- Pneumatic, spring return and hydraulic cylinders
- Electric motor actuators
- Stem extensions
Controls and safety
- Limit and proximity switches
- Solenoid valves, positioners, air sets
- Air tank fail-safe systems
- Mechanical lockouts
- OSHA gate guards
Wear and flow
- V-port inserts for throttling
- Deflector cones and hardsurfacing
- Purge and flushing ports
- Live-loaded packing, PTFE, graphite, Kevlar, food grade
- Specialty gate and exterior coatings
More from the Longview shop
Fabricast also builds the valves that usually sit next to a knife gate.
Slide gate valves
FIG 202 and FIG 215 slide gate valves. Add one line on typical service.
Check valves
Swing checks (FIG 7/27, FV 150-SC) and the FIG 6 tilting disc check in fabricated 304 or 316.
Wedge gate and sampling
FV 150-WG cast CF8M wedge gates, 1/2 in to 12 in. FIG SAM-15/20 sampling valves.
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