Typical Dual Plate Check Valve Wafer Type
Description
DUAL PLATE WAFER CHECK VALVE – TECHNICAL DATA SHEET
(Ductile Iron Body / Rubber Seat)
Project Name: ________________________
Item No.: ________________________
Tag No.: ________________________
Quantity: ________________________
Date: ________________________
1. VALVE GENERAL INFORMATION
| Parameter | Specification |
|---|---|
| Valve Type | Dual Plate Wafer Check Valve (Spring Assisted) |
| Body Construction | Wafer Type – Fits between pipe flanges |
| Body Material | Ductile Iron (ASTM A536 Grade 65-45-12 / GGG-50) |
| Seat Material | EPDM (Ethylene Propylene Diene Monomer) – Bonded/Lined type |
| Disc / Plate Material | Ductile Iron + Nickel Plated (Electroless Nickel Plating – ENP) |
| Stem / Hinge Pin Material | Stainless Steel (AISI 304 / 316) |
| Spring Material | Stainless Steel (AISI 302 / 304 / 316) |
| Nominal Size (DN / NPS) | 2″ – 24″ (DN50 – DN600) / Up to 48″ (DN1200) available |
| Pressure Rating | Class 125 / Class 150 / PN10 / PN16 |
| End Connection | Wafer Type |
| Design Standard | API 594 / API 6D / ASME B16.34 / ISO 5752 |
| Face-to-Face Standard | API 594 Short Pattern / ISO 5752 Series 20 |
| Flange Drilling Standard | ASME B16.1 (Class 125) / ASME B16.5 (Class 150) / EN 1092-2 |
| Inspection & Test Standard | API 598 / ISO 5208 / EN 12266-1 |
| Temperature Range | -30°C to +120°C (EPDM Seat) |
2. MATERIALS OF CONSTRUCTION
| No. | Component | Material | Remarks |
|---|---|---|---|
| 1 | Body | Ductile Iron (ASTM A536 65-45-12 / EN-GJS-450-10) | Epoxy coated (Internal/External) |
| 2 | Plates / Discs (2 pcs) | Ductile Iron + Electroless Nickel Plating (ENP) | Smooth finish, corrosion resistant |
| 3 | Seat | EPDM Rubber | 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 |
Alternative materials available upon request (NBR, Viton, Silicon, PTFE for seat; various disc materials available).
3. 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 |
4. APPLICABLE STANDARDS & SPECIFICATIONS
| Item | Standard |
|---|---|
| Design & Manufacturing | API 594 / API 6D / ASME B16.34 |
| Face-to-Face Dimensions | API 594 Short Pattern / ISO 5752 Series 20 |
| Flange Connection | ASME B16.5, ASME B16.47, EN 1092, JIS |
| Inspection & Testing | API 598 / ISO 5208 / EN 12266-1 |
| Coating Standard | WRAS approved epoxy powder at minimum 300 micron thickness |
5. PRESSURE TEST (PER API 598)
| Test Type | Description |
|---|---|
| Shell (Hydrostatic) | 100% hydraulic test with shell and seal |
| Seat Test | 100% hydraulic test and low pressure air test |
100% hydrostatic shell and seat test, plus low pressure air test performed on every valve.
6. PERFORMANCE DATA
| Parameter | Specification |
|---|---|
| Service Medium | Water, Wastewater, Oil, Gas, Non-Corrosive Fluids |
| Design Temperature | -30°C to +120°C (EPDM Seat) |
| Max. Working Pressure | Class 125 / Class 150 / PN10 / PN16 |
| Leakage Class | Bubble-tight shut-off (Zero leakage) |
| Cracking Pressure | Low – suitable for low flow applications |
| Installation Position | Horizontal or Vertical Upwards |
| Flow Direction | Uni-directional (marked on body) |
7. DIMENSIONS (Reference Only – EN 12334 PN10/PN16)
| DN (mm) | NPS (inch) | Face-to-Face L (mm) | Flange ØD (mm) | Flange ØD1 (mm) | Flange ØD2 (mm) |
|---|---|---|---|---|---|
| 40 | 1½″ | 54 | 92 | 58 | 46 |
| 50 | 2″ | 54 | 107 | 64 | 46 |
| 65 | 2½″ | 54 | 127 | 79 | 60 |
| 80 | 3″ | 57 | 142 | 94 | 70 |
| 100 | 4″ | 64 | 162 | 117 | 84 |
| 125 | 5″ | 70 | 192 | 145 | 115 |
| 150 | 6″ | 76 | 218 | 170 | 134 |
| 200 | 8″ | 95 | 273 | 224 | 184 |
| 250 | 10″ | 108 | 328 | 265 | 220 |
| 300 | 12″ | 143 | 378 | 310 | 260 |
| 350 | 14″ | 184 | 438 | 360 | 302 |
| 400 | 16″ | 192 | 489 | 410 | 350 |
| 450 | 18″ | 203 | 539 | 450 | 385 |
For detailed dimensional data per specific pressure rating and standard, please refer to API 594 or contact the manufacturer.
8. OPTIONAL UPGRADES
| Option | Description |
|---|---|
| Seat Material | NBR, Viton, Silicon, PTFE |
| Disc Material | CF8, CF8M, CF3, CF3M, 2205, 2507, C95400, C95800 |
| Body Material | Cast Iron, Carbon Steel WCB, Stainless Steel CF8/CF8M |
| Spring Material | Inconel X-750 |
| Coating | Epoxy coating (minimum 300 micron, WRAS approved) |
(FM and UL certification options have been removed per request.)
9. QUALITY CONTROL
-
100% chemical analysis and mechanical test with raw materials of each heat number
-
100% DPT test with castings; partly MT or UT test; RT always available if required
-
100% hydraulic test with shell and seal and low pressure air test
10. WARRANTY
12 months service life at minimum; free spares and maintenance instruction provided when required.
This technical data sheet is for reference purposes only. All specifications are subject to change without prior notice. For specific project requirements, please consult the manufacturer.







