Silent Check Valve -- Spring-Assisted Pump Discharge
Technical Datasheet -- Silent Non-Slam Spring-Assisted Check Valves for Pump Discharge
Document No.SV-DATA-SCV-001
RevisionA
DateMay 2026
ManufacturerSupreme Valves India, Ahmedabad, Gujarat, India
Silent (non-slam, spring-assisted) check valves for pump discharge, compressor, and water hammer-sensitive systems. Centrally-guided disc with calibrated spring return provides rapid, controlled closure before flow reversal, eliminating water hammer and pipeline vibration. Wafer, lug, or flanged design. Horizontal, vertical, or inclined installation. Low cracking pressure (0.02--0.05 bar). SS316, WCB, or ductile iron body with Stellite seat overlay. API 594 / ASME B16.34 / AWWA C508 compliant.
Technical Specifications
| Parameter | Specification |
|---|
| Product Type | Silent Check Valves |
| Category | Check Valves |
| Size Range | 2" to 48" (DN50 to DN1200) |
| Pressure Class | Class 150 / Class 300 / Class 600 / PN10 / PN16 / PN25 / PN40 per ASME B16.5 / EN 1092-1 |
| End Connections | Wafer type (fits between flanges) or Lug type (through-bolted) or RF flanged per ASME B16.5 / EN 1092-1 |
| Body Material | ASTM A216 WCB / ASTM A351 CF8M (SS316) / ASTM A217 WC6 (high temp) / Ductile Iron EN-GJS-500-7 (GGG50, water service) |
| Disc Material | SS316 with Stellite 6 overlay / SS316 with ENP or chrome plating / Ductile iron with EPDM/NBR coating (water service) |
| Guide / Bushing Material | SS316 with bronze or PTFE-lined bushing / SS410 with Stellite bushing |
| Spring Material | SS316 (standard) / Inconel X-750 (high temp) / Elgiloy (corrosion resistant, seawater) |
| Seat Material | SS316 with Stellite 6 overlay / SS316 with ENP -- integral or renewable seat ring |
| Face-to-Face | API 594 wafer pattern or ASME B16.10 short pattern / manufacturer's standard for silent check design |
| Orientation | Horizontal or vertical (spring-assisted closure works in all orientations) |
| Cracking Pressure | 0.02 to 0.05 bar (spring pre-load) -- dependent on spring rate and disc weight |
| Leakage Class | API 598 / EN 12266-1 -- metal seated standard leakage acceptable; soft seat option: Class A |
| Temperature Range | -29 deg C to +425 deg C (WCB/SS316) -- up to +540 deg C (WC6/Inconel spring) |
Materials of Construction
| Component | Material |
|---|
| Carbon Steel | ASTM A216 WCB body and disc (standard industrial) |
| Stainless Steel | ASTM A351 CF8M (SS316) body, disc, guide, and seat (corrosive / standard service) |
| Alloy Steel | ASTM A217 WC6 body and disc (high temperature > 425 deg C) |
| Ductile Iron | EN-GJS-500-7 (GGG50) epoxy-coated body and disc with EPDM/NBR coating (economical water / HVAC) |
| Seat Overlay | Stellite 6 on SS316 seat for erosion and wear resistance |
| Spring | SS316 (standard), Inconel X-750 (high temp > 400 deg C), Elgiloy (seawater / corrosion resistant) |
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 | API 594 Check Valves, ASME B16.34, AWWA C508 (resilient-seated check valves, reference), EN 12334 |
Notes
- Pump flow rate, head, pipe size, and flow reversal characteristics (centrifugal vs reciprocating pump) must be specified by the purchaser for correct spring rate and closure timing calculation.
- For high-temperature steam service (> 425 deg C), material upgrade to WC6 body with Inconel X-750 spring is required.
- For seawater or brine service, SS316 or duplex stainless steel body with Elgiloy spring is recommended; WCB will corrode without protective coating.
- For frequent flow reversal or pulsating flow (reciprocating pumps, compressors), centrally-guided design with heavy-duty spring and Stellite seat overlay is strongly recommended.
- All valves are manufactured by Supreme Valves India as per our standard specifications.
