Rubber Seated Dual Plate Check Valve
Description
Technical Datasheet: Dual Plate Wafer Check Valve
(Ductile Iron Body / Nickel Plated Discs / SS Stem & Springs / EPDM Seat)
Project Name: ____________________ Item No.: ____________________
Tag No.: ____________________ Quantity: ____________________
1. General Information
| Item | Standard Configuration | User Specification / Remarks |
|---|---|---|
| Valve Type | Dual Plate Wafer Check Valve (Spring Assisted) | |
| Body Material | Ductile Iron (ASTM A536 Grade 65-45-12 / GGG-50) | Epoxy coated |
| Disc / Plate Material | Ductile Iron + Nickel Plated (Electroless Nickel Plating – ENP) | Corrosion resistant finish |
| Stem / Hinge Pin Material | Stainless Steel (AISI 304 / 316) | |
| Spring Material | Stainless Steel (AISI 302 / 304 / 316) | |
| Seat Material | EPDM (Ethylene Propylene Diene Monomer) | Bonded / Lined type |
| Design Standard | API 594 / API 6D / ASME B16.34 / ISO 5752 | |
| Face-to-Face | API 594 Short Pattern / ISO 5752 Series 20 | |
| Flange Drilling | ASME B16.1 (Class 125) / ASME B16.5 (Class 150) / EN 1092-2 | |
| Inspection & Test | API 598 / ISO 5208 / EN 12266-1 | |
| Pressure Rating | Class 125 / Class 150 / PN10 / PN16 | |
| Size Range | 2″ – 24″ (DN50 – DN600) | |
| Temperature Range | -30°C to +120°C (EPDM Seat) | |
| End Connection | Wafer Type (Fits between flanges) | |
| Installation Position | Horizontal or Vertical Upwards |
2. Design Features
| Feature | Description | Benefit |
|---|---|---|
| Dual Plate Design | Two spring-loaded plates hinged on a central pivot | Compact, lightweight, quick closing |
| Spring Assisted Closing | Stainless steel torsion springs force plates closed when flow stops | Prevents slamming and water hammer |
| Nickel Plated Discs | Electroless nickel plating on ductile iron plates | Excellent corrosion resistance, smooth surface reduces friction |
| Short Face-to-Face | Very compact body length per API 594 | Saves space, reduces installation cost |
| Non-Slam Operation | Plates close before flow reversal | Eliminates damaging pressure surges |
| Low Cracking Pressure | Lightweight plates require minimal pressure to open | Suitable for low flow applications |
| Full Opening | Plates open to 85°-90° | Low pressure drop |
| EPDM Soft Seat | Resilient EPDM seat for bubble-tight shut-off | Zero leakage, excellent for water service |
3. Bill of Materials (Main Components)
| No. | Part Name | Material | Remarks |
|---|---|---|---|
| 1 | Body | Ductile Iron (ASTM A536 65-45-12) | Epoxy coated (Internal/External) |
| 2 | Plates / Discs (2 pcs) | Ductile Iron + Nickel Plated (Electroless Nickel Plating) | Smooth finish, corrosion resistant |
| 3 | Seat | EPDM (Ethylene Propylene Diene Monomer) | Bonded to body / Replaceable type |
| 4 | Springs (2 pcs) | Stainless Steel (AISI 302 / 304) | Torsion springs |
| 5 | Hinge Pin / Stem | Stainless Steel (AISI 304 / 316) | Central pivot pin |
| 6 | Stop Pin / Limiter | Stainless Steel (AISI 304) | Limits plate travel |
| 7 | Bushings / Bearings | PTFE / Bronze backed PTFE | For smooth plate rotation |
| 8 | Nameplate | Stainless Steel / Aluminum | |
| 9 | Fasteners | Stainless Steel (304) | For nameplate / accessories |
4. Technical Parameters & Performance
| Item | Specification |
|---|---|
| Medium | Water, Wastewater, Seawater, Cooling Water, Mild Chemicals (____________________) |
| Operating Temperature | -30°C to +120°C (EPDM Seat) |
| Max Operating Pressure | Up to 200 psi / 16 bar (De-rate at high temps) |
| Seat Type | Soft Seat – EPDM (Resilient) |
| Sealing Performance | Zero Leakage (Bubble tight) – API 598 / ISO 5208 Rate A |
| Flow Direction | Unidirectional (Arrow marked on body) |
| Cracking Pressure | Very low (2-5 psi / 0.14-0.34 bar typical) |
| Flow Characteristic | Low pressure drop, plates open fully at low velocity |
| Spring Material | Stainless Steel – Corrosion resistant |
| Sour Service | Not applicable (EPDM not suitable for hydrocarbons) |
| Backflow Prevention | Instantaneous closure upon flow reversal |
5. Test Pressure (Reference: Class 150 / PN16)
| Test Type | Pressure | Standard |
|---|---|---|
| Shell (Hydrostatic) | 1.5 x Rated Pressure (425 psi / 2.9 MPa for Class 150) | API 598 / ISO 5208 |
| Seat (Hydrostatic) | 1.1 x Rated Pressure (315 psi / 2.2 MPa for Class 150) | API 598 / ISO 5208 |
| Low Pressure Seat (Air) | 80 psi / 0.6 MPa | Bubble tight (Rate A) |
6. Dimensions & Weight (Reference: API 594 / Class 150 / Wafer Type)
| NPS | DN (mm) | L (Face-to-Face) mm | Weight (kg) approx |
|---|---|---|---|
| 2″ | 50 | 43 | 1.5 |
| 2-1/2″ | 65 | 46 | 2.4 |
| 3″ | 80 | 64 | 3.6 |
| 4″ | 100 | 64 | 5.7 |
| 5″ | 125 | 70 | 7.3 |
| 6″ | 150 | 76 | 9.0 |
| 8″ | 200 | 89 | 17.0 |
| 10″ | 250 | 114 | 26.0 |
| 12″ | 300 | 114 | 38 |
| 14″ | 350 | 127 | 55 |
| 16″ | 400 | 140 | 75 |
| 18″ | 450 | 152 | 105 |
| 20″ | 500 | 152 | 115 |
| 24″ | 600 | 178 | 170 |
| (Note: Dimensions are for reference only. For exact dimensions, refer to certified GA drawing.) |
7. Special Requirements / Options
-
Seat Material: EPDM (Standard) / Buna-N (NBR) / Viton (FKM) / Silicone
-
Disc Material: Nickel Plated Ductile Iron (Standard) / Stainless Steel 304/316 / Nylon Coated
-
Stem Material: Stainless Steel 304 (Standard) / 316 / 17-4PH / Monel
-
Spring Material: Stainless Steel 302 (Standard) / 316 / Inconel
-
Body Coating: Epoxy coating (Min. 250 microns) – Color: Blue / RAL 5015 / Custom
-
Test Certificate: EN 10204 Type 2.2 / 3.1
-
Special Cleaning: For Potable Water (NSF/ANSI 61) / Food grade
-
Lifting Lug: Yes / No (For larger sizes)
-
Vertical Down Installation: Consult manufacturer (spring modification may be required)
-
NACE Compliance: MR0175 / ISO 15156 (For modified materials)
Material Notes:
-
Ductile Iron (ASTM A536 65-45-12): High strength, excellent impact resistance, commonly used in water and wastewater applications.
-
Nickel Plated Discs (Electroless Nickel Plating – ENP): Provides uniform corrosion resistance, hardness, and lubricity. Ideal for water, seawater, and mild chemical service.
-
Stainless Steel Springs & Stem: Ensures long-term reliability and corrosion resistance in aqueous environments.
-
EPDM Seat: Excellent resistance to hot water, steam, ozone, UV, and mild chemicals. Not recommended for oils, hydrocarbons, or solvents.
Application Notes:
-
Suitable for: Water distribution, wastewater treatment, cooling water systems, fire protection, irrigation, and pumping stations.
-
Not suitable for: Hydrocarbon fuels, oils, solvents, or high-temperature steam (>120°C).
-
Installation: Install with flow direction matching arrow on body. For vertical installation, ensure upward flow direction.
Note: This datasheet is prepared for a Dual Plate Wafer Check Valve with Ductile Iron body, Nickel Plated discs, Stainless Steel internals, and EPDM seat per API 594 / API 598. Ensure selected materials and seat are compatible with the specific service medium and temperature range.
