Knife Gate Valve -- MSS SP-81 SS316
Technical Datasheet -- Bidirectional Knife Gate Valves for Slurry and Pulp Service
Document No.SV-DATA-KGV-001
RevisionA
DateMay 2026
ManufacturerSupreme Valves India, Ahmedabad, Gujarat, India
Bidirectional knife gate valves for slurry, pulp, paper, mining, and wastewater applications. Sharp-edged SS316 knife gate cuts through suspended solids and fibrous media without jamming. MSS SP-81 / EN 12334 compliant. Wafer or lug body with replaceable soft seat and gate.
Technical Specifications
| Parameter | Specification |
|---|
| Product Type | Knife Gate Valves |
| Category | Gate Valves |
| Size Range | 2" to 48" (DN50 to DN1200) |
| Pressure Rating | PN10 / PN16 / Class 150 |
| End Connections | Wafer type or Lug type per MSS SP-81 |
| Body Material | ASTM A351 CF8M (SS316) / ASTM A216 WCB with SS316 gate |
| Gate Material | SS316 knife-edge gate with Stellite or chrome plating on cutting edge |
| Seat Material | EPDM / NBR / Viton (FPM) / PTFE / metal seat (bi-directional sealing) |
| Stem Material | SS316 rising stem with two-piece stem coupling for in-line replacement |
| Face-to-Face | MSS SP-81 short pattern (compact wafer design) |
| Operation | Handwheel (standard) / Bevel gear (large sizes) / Pneumatic cylinder / Electric actuator |
| Leakage Class | MSS SP-81 / EN 12334 -- zero visible leakage for soft-seated valves |
| Temperature Range | -20 deg C to +120 deg C (EPDM) -- up to +200 deg C (PTFE/metal seat) |
Materials of Construction
| Component | Material |
|---|
| Stainless Steel | ASTM A351 CF8M (SS316) body and gate -- corrosion and abrasion resistant |
| Carbon Steel | ASTM A216 WCB body with SS316 gate and liner (economical option) |
| Seat Elastomers | EPDM (water / slurry), NBR (oil), Viton FPM (chemical), PTFE (high temp / chemical) |
| Gate Overlay | Stellite 6 or hard chrome plating on cutting edge for extended wear life in abrasive service |
Testing & Inspection
| Test | Requirement |
|---|
| Testing | Hydrostatic shell test 1.5 x WP per API 598 / EN 12266-1; Seat leakage test per API 598 / EN 12266-1; Functional test -- full stroke, torque; Material certificates per EN 10204 3.1 |
| Certification | ISO 9001:2015 QMS, EN 10204 3.1 material certificates, hydrostatic and seat test reports |
Applicable Standards
| Standard | Description |
|---|
| Design Standard | MSS SP-81 Steel Knife Gate Valves, EN 12334 |
Notes
- Slurry concentration, particle size, and abrasiveness must be specified by the purchaser for correct seat and liner material selection.
- For highly abrasive service, Stellite overlay on gate edge and polyurethane body liner are strongly recommended.
- For high-temperature service (> 200 deg C), PTFE or metal seat is required.
- All valves are manufactured by Supreme Valves India as per our standard specifications.
