Steam Trap -- Thermodynamic SS316
Technical Datasheet -- Disc-Type Thermodynamic Steam Traps for High-Pressure Steam Systems
Document No.SV-DATA-ST-TD-001
RevisionA
DateMay 2026
ManufacturerSupreme Valves India, Ahmedabad, Gujarat, India
Thermodynamic (disc-type) steam traps for high-pressure steam systems. Operate on the thermodynamic principle of flash steam velocity difference between condensate and live steam -- no external power, floats, or levers required. Compact, lightweight, and resistant to water hammer and freezing. SS316 or WCB body with Stellite-seated hardened disc. In-line repairable by removing the bolted cover. Suitable for steam distribution, process heating, tracing, and refinery applications up to 80 bar.
Technical Specifications
| Parameter | Specification |
|---|
| Product Type | Thermodynamic Steam Traps |
| Category | Steam Traps |
| Product Type | Thermodynamic Steam Trap (Disc Type) |
| Category | Steam Traps |
| Size Range | 1/2" to 2" (DN15 to DN50) -- other sizes on request |
| Pressure Rating | PN16 / PN40 / Class 150 / Class 300 / Class 600 -- up to 80 bar (1160 psi) |
| End Connections | Threaded NPT / BSP, Socket Weld, Flanged RF per ASME B16.5 / EN 1092-1 |
| Body Material | ASTM A351 CF8M (SS316) / ASTM A216 WCB / ASTM A105 (forged carbon steel) |
| Disc Material | SS316 hardened disc with Stellite 6 or chrome plating on seating surface |
| Seat Material | SS316 with Stellite 6 overlay -- ground and lapped to mirror finish |
| Cover / Bonnet | SS316 or WCB bolted cover with spiral wound SS316/graphite gasket |
| Operation Principle | Thermodynamic -- flash steam velocity lifts the disc off the seat; condensate velocity is insufficient to lift disc, allowing discharge |
| Discharge Mode | Intermittent -- disc opens and closes cyclically based on steam/condensate mix at the trap inlet |
| Back Pressure Tolerance | Up to 80% of inlet pressure (standard thermodynamic disc trap) |
| Air Venting | Automatic air venting on start-up -- cold air and condensate discharge freely until steam reaches the trap |
| Freeze Protection | Disc-type design is inherently resistant to freezing damage because the body is self-draining when installed vertically |
| Temperature Range | Up to +425 deg C (WCB / SS316) -- up to +540 deg C (WC6 body on request) |
Materials of Construction
| Component | Material |
|---|
| Stainless Steel | ASTM A351 CF8M (SS316) body, disc, and seat (corrosive / hygienic service) |
| Carbon Steel | ASTM A216 WCB body or ASTM A105 forged body (standard industrial steam) |
| Alloy Steel | ASTM A217 WC6 body (high-temperature steam > 425 deg C on request) |
| Seat Overlay | Stellite 6 on SS316 seat for erosion and wear resistance at high-velocity steam flash |
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 | ISO 6552 (reference), BS 6023, manufacturer's standard |
Notes
- Operating pressure and condensate load must be specified by the purchaser for correct disc sizing and capacity verification.
- Thermodynamic traps are not recommended for applications with significant back pressure (> 80% of inlet pressure) or where continuous condensate discharge is required -- consider float-type or inverted bucket traps for these services.
- For superheated steam service (> 200 deg C superheat), contact engineering for special disc material and seat design.
- Install with body vertical and flow direction downward for proper self-draining and freeze protection.
- All valves are manufactured by Supreme Valves India as per our standard specifications.
