20″-150LB 3-Piece Trunnion Mounted Ball Valve
Description
Technical Data Sheet
3-Piece Trunnion Mounted Ball Valve
Project/Item: 3-Piece Fixed Ball Valve
Valve Size: 20 inches (20″)
Pressure Rating: 150LB (Class 150)
Model: Q347F-150Lb (Example, confirm with manufacturer)
1. General Information
| Item | Technical Parameter | Remarks |
|---|---|---|
| Valve Type | 3-Piece Trunnion Ball Valve | Side Entry, Bolted Bonnet Construction |
| Nominal Bore | 20 inches (DN500) | Full Bore Design |
| Pressure Class | 150 LB (Class 150) | Corresponds to PN20 |
| Connection Type | Flanged Ends (RF) | Raised Face Flanges per ASME B16.5 |
| Operation Type | Worm Gear Operator | Suitable for large bore valves, low torque |
| Design Standard | API 6D / ASME B16.34 | Pipeline valve design specification |
| Face-to-Face | ASME B16.10 | For RF flanged ends |
| Flange Standard | ASME B16.5 | Flange dimensions and drilling |
| Inspection & Test | API 598 | Pressure test standards |
2. Main Technical Parameters & Performance
| Item | Technical Parameter | Remarks |
|---|---|---|
| Shell Test Pressure | 3.1 MPa | Hydrostatic, ambient temperature |
| High-Pressure Seal Test | 2.2 MPa | Hydrostatic, ambient temperature |
| Low-Pressure Seal Test | 0.5 – 0.7 MPa | Air or Nitrogen |
| Temperature Range | -29°C ~ +200°C | Depends on seat material selection (e.g., PTFE) |
| Applicable Media | Water, Oil, Natural Gas, Steam | WCB body suitable for non-corrosive & mildly corrosive media |
| Operator | Turbine (Worm Gear) | Standard |
| Fire Safe Design | API 607 | Optional; ensures sealing during fire conditions |
| Anti-Static Device | Yes | Springs and balls to dissipate static charge |
| Blow-out Proof Stem | Yes | Stem designed with an integral shoulder |
3. Main Material Specifications
Based on WCB Body + 316 Trim requirements:
| Part Name | Material Type | Material Grade | Standard / Remarks |
|---|---|---|---|
| Body / Bonnet | Carbon Steel | A216 WCB | Cast steel suitable for 3-piece design |
| Ball | Stainless Steel | A182 F316 | 316 SS, may be hardened (Chrome Plated) |
| Stem | Stainless Steel | A182 F316 | High strength, good corrosion resistance |
| Seat Insert (Ring) | Reinforced PTFE | RPTFE / Nylon | Or PPL (High temp version) |
| Seat Support / Holder | Stainless Steel | A182 F316 | Supports the soft seal ring |
| Springs | Alloy Steel | 17-7PH / Inconel | Preloads the seats for low-pressure sealing |
| Studs / Bolts | Alloy Steel | A193 B7 | High strength alloy steel |
| Nuts | Carbon Steel | A194 2H | Standard heavy hex nuts |
| Packing / Gasket | Flexible Graphite / PTFE | / | Optional Low-Emission packing available |
4. Main Dimensions (For 20″ Class 150)
Typical dimensions per ASME standards. Variations may occur between manufacturers.
| Description | Dimensions (mm) | Dimensions (inches) | Remarks |
|---|---|---|---|
| Port Diameter (d) | 489 | 19.25″ | Full bore (approx) |
| Flange O.D. (D) | 698 | 27.5″ | Per ASME B16.5 20″ Class 150 |
| Bolt Circle (D1) | 635 | 25.0″ | |
| Flange Thickness (b) | 42.9 | 1.69″ | |
| No. of Holes – Dia | 20 – Φ32 mm | 20 – 1.25″ | 20 bolt holes |
| Face-to-Face (L) | 914 | 36.0″ | Flanged RF to RF (ASME B16.10) |
| Center to Top (H1) | ~590 | ~23.2″ | Approx, from stem center to top of valve |
| Gearbox Height (H2) | ~840 | ~33.1″ | Total height with gearbox (approx) |
| Handwheel Dia (Do) | ~800 | ~31.5″ | Reference |
| Approx Weight (WT) | ~1190 kg | ~2620 lbs | Estimated, cast steel body |
5. Design Features & Requirements
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3-Piece Bolted Body: The body consists of three parts (Body + 2 End Caps) bolted together. This allows for easy maintenance (seat/ball replacement) without removing the entire valve from the pipeline.
-
Trunnion Mounted Ball: The ball is fixed and supported by upper and lower stems/bearings. This design is ideal for 20″ large bore applications, reducing operating torque and ensuring stable performance under high differential pressure.
-
Double Piston Effect (DPE) Seats: Standard seats provide bidirectional sealing. The valve typically features automatic cavity pressure relief (the upstream seat acts as a piston, allowing overpressure in the body cavity to vent into the pipeline).
-
Emergency Sealant Injection: The valve body is equipped with sealant injection fittings. In case of seat damage, sealant can be injected to temporarily restore sealing.
-
Anti-Static Device: A spring-loaded plunger/ball ensures electrical continuity between the ball, stem, and body to prevent static spark buildup.
-
Secondary Metal Seal: In the event the soft seat is destroyed by fire, the ball will contact the metal seat support, providing a metal-to-metal seal (Fire Safe feature).
Note:
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This data sheet is based on standard ASME/API specifications.
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The gearbox dimensions (height, handwheel size) and overall weight may vary depending on the manufacturer and gearbox model. Please refer to the final manufacturer’s drawing for certified dimensions.
