12″-150LB Wafer Knife Gate Valve – Technical Data Sheet
- General Description
Product Name: Wafer Type Knife Gate Valve
Model: 12″-150LB
Nominal Diameter: 12 inches (NPS 12, DN 300)
Clase de presión: Class 150 (ANSI 150LB)
Connection Type: Wafer type
Product Introduction:
The knife gate valve is a shut‑off valve specifically designed for slurries, granular materials and fibrous media. Its key closure member is a gate with a sharp knife edge. When fully open, the gate is completely lifted above the valve body, allowing the medium to pass straight through with a smooth, unobstructed flow path, minimizing sediment accumulation. During closing, the sharp lower edge of the gate easily cuts through solid particles and fibrous debris in the flow channel, ensuring a tight shut‑off. The 12″-150LB wafer knife gate valve is suitable for low to medium pressure applications and is widely used in mining, metallurgy, papermaking, chemical industry, power generation, wastewater treatment and food processing.
- Estándares de diseño
Item | Estándar |
Design & Manufacture | MSS SP‑81, JB/T 8691 |
Face‑to‑Face (Structure Length) | MSS SP‑81, TAPPI TIS 405.8, GB/T 15188.2 |
Flange Connection Dimensions | ANSI B16.5 Class 150 |
Inspection & Testing | MSS SP‑81, API 598, GB/T 13927 |
Pressure‑Temperature Rating | ASME B16.34 |
MSS SP‑81 applies to bonnetless, metal‑seated knife gate valves from NPS 2 to NPS 36 and specifies pressure limits and material requirements. For sizes 2″ to 24″, the maximum working pressure is 150 psi.
- Main Technical Parameters
Parámetro | Value |
Nominal Pipe Size (NPS) | 12″ (DN 300) |
Pressure Class | Class 150 (150 LB) |
Maximum Working Pressure | 150 psi (10.3 bar) |
Face‑to‑Face Dimension L | 8″ (approx. 203 mm)* |
Flange Standard | ASME B16.5 Class 150 |
Flange Facing | RF (Raised Face) / FF (Flat Face) |
Connection Type | Wafer type |
Actuación | Handwheel (manual) / Pneumatic / Electric / Electro‑hydraulic |
Temperature Range | -29°C to +425°C (depending on seat material) |
Suitable Media | Pulp, sewage, coal slurry, ash, gypsum slurry, powder, etc. |
Tipo de válvula | Bonnetless, rising stem |
*Note: Face‑to‑face dimensions may vary slightly. For 12″ size, typical dimension is 8″ (203 mm). Full open height approx. 45″ (1143 mm), handwheel diameter approx. 18″ (457 mm).
- Dimensional Data (Reference for 12″ Class 150 Wafer Knife Gate Valve)
NPS | Face‑to‑Face L (mm) | Flange OD D (mm) | Bolt Circle D1 (mm) | No. of Bolt Holes | Bolt Hole Dia. (mm) |
12″ | approx. 203 | approx. 505 | approx. 470 | 12 | approx. 25 |
Note: Flange dimensions strictly conform to ASME B16.5 Class 150.
- Main Component Materials
Componente | Available Materials |
Cuerpo | Carbon steel WCB, CF8 (304 SS), CF8M (316 SS), Ductile iron, Duplex stainless steel |
Gate | 304 SS, 316 SS, 2205 Duplex SS, 17‑4 PH SS |
Provenir | 304 SS, 316 SS, 17‑4 PH SS |
Asiento | EPDM (-50°C ~ +150°C), NBR (-40°C ~ +100°C), PTFE, Polyurethane (PU), Metal hard‑seat |
Packing Gland | 304 SS, 316 SS, Ductile iron |
Packing | PTFE, Graphite, Lubricated packing |
Fasteners | Stainless steel A4‑70 / A2‑70 |
Material Notes:
- Body material: MSS SP‑81 requires ASTM A216 WCB cast steel for corrosion resistance and pressure integrity.
- Seat material: Resilient seats (EPDM, NBR, polyurethane) are suitable for slurry media and provide bubble‑tight shut‑off; metal seats are for high temperature or dry media with better wear resistance.
- Gate material: Stainless steel gate is polished on both sides to prevent clogging and protect the seat.
- Structural Features & Advantages
No. | Feature | Descripción |
1 | Wafer design | Compact, lightweight, space‑saving – the valve body has no integral flanges and is clamped between pipeline flanges. |
2 | Bonnetless design | The gate lifts completely above the body, preventing media accumulation and clogging. |
3 | Sharp knife edge | The gate bottom has a blade that cuts through solids and fibers during closing, ensuring reliable shut‑off. |
4 | U‑cup seal | Newly developed U‑cup seal design provides excellent sealing performance. |
5 | Replaceable seat | Resilient seats can be easily replaced on‑site, reducing maintenance cost. |
6 | Bidirectional sealing | Optional bidirectional sealing design meets different pressure requirements. |
7 | Body guide | Guides in the body ensure accurate and stable gate movement. |
8 | Self‑adjusting packing | Self‑adjusting packing gland provides effective stem sealing while also cleaning the gate. |
- Performance Data
Test | Test Pressure | Acceptance Criteria |
Shell (Strength) Test | 1.5 × rated pressure (225 psi) | No visible leakage per MSS SP‑81 / API 598 |
High‑Pressure Seat Test | 1.1 × rated pressure (165 psi) | No visible leakage per MSS SP‑81 / API 598 |
Low‑Pressure Seat Test | As per standard | API 598 |
Stem Seal Test | As per standard | No visible leakage |
Clase de fuga:
- Resilient seats (EPDM/NBR/PU): Bubble‑tight shut‑off (zero leakage)
- Metal hard seat: ANSI/FCI 70‑2 Class III or Class IV
MSS SP‑81 requires a hydrostatic test at 1.5 times the rated working pressure to verify pressure‑containing integrity and sealing performance.
- Applications & Industries
Industry | Typical Media | Remarks |
Mining / Metallurgy | Ore slurry, tailings, coal slurry, ash | Knife edge cuts solid particles; wear‑resistant |
Paper & Pulp | Pulp, white water, black liquor | Gate easily cuts fibrous pulp without wrapping |
Wastewater Treatment | Raw sewage, sludge, sand | Handles fibrous and solid‑laden wastewater |
Power Generation | Fly ash, bottom ash, limestone slurry (FGD systems) | Wear‑resistant, suitable for FGD slurry |
Chemical Industry | Corrosive slurries, powders | Option of stainless steel, duplex or special alloys |
Food Industry | Food slurries, syrups | Hygienic design, easy to clean |
- Actuation Options
Actuación | Descripción | Typical Application |
Manual (Handwheel) | Rising stem handwheel, low torque, easy operation | General service, no automation |
Manual (Chainwheel) | Chain operation for high or hard‑to‑reach locations | Overhead installations |
Pneumatic Actuator | Double‑acting or spring‑return, fast stroke | Automated lines, explosion‑proof areas |
Electric Actuator | Remote control capability | Centralized control, intelligent systems |
Electro‑hydraulic Actuator | Smooth operation, low impact | High‑pressure service, precise positioning |
- Installation & Maintenance Instructions
- Installation direction: For uni‑directional valves, follow the flow arrow on the body. Bi‑directional valves have no orientation restriction.
- Flange alignment: Ensure the pipe flanges are precisely aligned to avoid uneven loading and leakage.
- Bolting: Use long bolts passing through the valve body and both pipe flanges. Tighten diagonally and evenly.
- Packing maintenance: If packing leaks, tighten the packing gland bolts. Replace packing if worn out.
- Seat maintenance: Clean the sealing area or replace the seat if damaged or contaminated.
- Not for throttling: Knife gate valves are designed for fully open or fully closed service only – not for flow regulation.
- Regular lubrication: Lubricate the actuation mechanism and stem periodically to ensure smooth operation.
- Quality Assurance & Inspection
Inspection Item | Details |
Shell (Strength) Test | 100% at 1.5× rated pressure, no visible leakage |
Seat Leakage Test | 100% at 1.1× rated pressure, leakage meets standard requirements |
Material Verification | Material certificate provided (EN 10204 3.1 or 3.2) |
Visual Inspection | 100% – no defects, uniform coating |
Dimensional Check | 100% inspection per drawing |
Functional Test | Smooth opening/closing, no sticking or binding |
All tests are performed in accordance with MSS SP‑81 and API 598.
GARANTÍA:
SAVVY VALVES se compromete a ofrecer una calidad de producto excepcional y un servicio posventa sin complicaciones. Nuestras válvulas tienen una vida útil mínima garantizada de 12 meses, durante los cuales suministraremos todos los repuestos necesarios e instrucciones detalladas de mantenimiento de forma gratuita. Durante el período de garantía, si se produce algún daño no provocado por el hombre, reemplazaremos los componentes sin coste alguno y ofreceremos soporte técnico profesional. Una vez vencida la garantía, los clientes solo deberán pagar el coste de los repuestos y seguirán beneficiándose de descuentos en los servicios de mantenimiento. Nuestro objetivo es ayudar a los clientes a reducir los costes operativos y mejorar la eficiencia de la producción mediante una calidad fiable y un soporte posventa integral. Ya sea para consultas técnicas o necesidades de mantenimiento, nuestro equipo de expertos responderá con prontitud para garantizar que su sistema de válvulas mantenga un rendimiento óptimo en todo momento.