3/4″-2500LB Welded Bonnet Globe Valve
Description
TECHNICAL DATA SHEET
Product Name: 3/4-inch 2500LB Welded Bonnet Globe Valve
Model/Specification: 3/4″-2500LB-WELDED-GLOBE
Valve Type: Welded Bonnet Globe Valve (Forged)
Connection Type: Socket Weld (SW) / Butt Weld (BW) / Threaded (NPT) User specified
1. Basic Design Parameters
| Parameter | Standard/Specification |
|---|---|
| Size | 3/4 inch (DN20) |
| Pressure Class | Class 2500 LB (PN420 / 6000 PSI) |
| Body Material | Forged Carbon Steel (A105) / Forged Stainless Steel (A182 F304/F316) / Alloy Steel (F22) User specified |
| Manufacturing Process | Close Die Forged Steel |
| Design Standard | API 602 / ASME B16.34 / BS 5352 |
| Bonnet Type | Welded Bonnet (Threaded-in and strength-welded) |
| End Connection Standard | ASME B16.11 (SW) / ASME B16.25 (BW) / ASME B1.20.1 (NPT) |
| Face to Face Standard | ASME B16.10 |
| Test & Inspection Std. | API 598 |
2. Technical Specifications
| Parameter | Details |
|---|---|
| Valve Type | Straight Pattern Globe Valve, Forged Construction |
| Bonnet Type | Welded Bonnet – Threaded-in and seal welded for zero leakage |
| Stem Type | Outside Screw and Yoke (OS&Y), Rising Stem |
| Disc Type | Parabolic / Needle-type Disc (for throttling) |
| Seat Type | Integral Seat (hardfaced optional) |
| Applicable Media | Steam, Water, Oil, Gas, Corrosive Fluids (depending on material) |
| Temperature Range | -29°C to +550°C (depending on material) |
| Flow Direction | Flow under disc (standard) |
| Operation | Handwheel (standard) / Gear / Actuator |
| Backseat Design | Standard (protects packing when fully open) |
3. Material of Construction (Recommended – Carbon Steel A105)
| Part Name | Material | Standard/Grade |
|---|---|---|
| Body | Forged Carbon Steel | ASTM A105 |
| Bonnet | Forged Carbon Steel | ASTM A105 |
| Disc / Valve Plug | Stainless Steel + Hardfacing | 13Cr / F304 + Stellite (optional) |
| Seat Ring | Integral Seat (Hardfaced optional) | 13Cr / F304 |
| Stem | Stainless Steel | ASTM A182 F6a (13Cr) / F304 |
| Gasket | None (Welded Bonnet – no gasket) | — |
| Packing | Flexible Graphite / PTFE | Low sulfur graphite |
| Stem Nut | Aluminum Bronze | C95400 / CuAl10Fe3 |
| Body Bolts/Nuts | None (Welded Bonnet) | — |
| Handwheel | Malleable Iron / Carbon Steel | ASTM A197 |
*For Stainless Steel version (A182 F304/F316): body/bonnet to SS, disc/stem to SS.*
4. Main Dimensions & Connection Details
*Note: Dimensions for 3/4″ Class 2500 Welded Bonnet Globe Valve with Socket Weld Ends. Based on API 602 and industry standards .*
4.1 End-to-End Dimensions (Face-to-Face – Socket Weld)
| Size | Pressure Class | L (mm) | L (in) | H (Open) mm | H (Open) in | W (Handwheel) mm | Weight (kg) | Weight (lbs) |
|---|---|---|---|---|---|---|---|---|
| 3/4″ | 2500LB | 92 | 3.62 | ~171 | ~6.73 | 100 | ~1.9 | ~4.2 |
Note: Welded bonnet version is slightly lighter than bolted bonnet (approx 0.2 kg less) .
4.2 End Preparation Details (Per ASME Standards)
| Connection Type | Standard | Details |
|---|---|---|
| Socket Weld (SW) | ASME B16.11 | 3/4″ Socket Weld, bore to match pipe schedule (Sch. 160 / XXS) |
| Butt Weld (BW) | ASME B16.25 | Bevel: 37.5°, Root face: 1.6 mm |
| Threaded (NPT) | ASME B1.20.1 | 3/4″ NPT Female |
4.3 Welded Bonnet Design Details
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Bonnet Attachment: Threaded-in to precise torque, then seal welded
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Weld Type: Full penetration strength weld
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Leakage Protection: Dual protection – threads + strength weld
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Gasket: None (eliminates gasket leak path)
5. Pressure-Temperature Rating (ASME B16.34 / Class 2500)
Material Group: Carbon Steel (ASTM A105)
| Temperature (°C) | Working Pressure (bar) | Working Pressure (psi) | Notes |
|---|---|---|---|
| -29 to 38 | 420 | 6090 | Maximum Rating (Class 2500) |
| 100 | 395 | 5730 | |
| 200 | 360 | 5220 | |
| 300 | 320 | 4640 | |
| 400 | 285 | 4135 | |
| 425 | 245 | 3550 | Max for A105 |
*For Stainless Steel (F304/F316): similar ratings up to 550°C with derating .*
6. Test Pressure (API 598)
| Test Type | Medium | Pressure (bar) | Pressure (psi) | Acceptance Criteria |
|---|---|---|---|---|
| Shell Test (Hydrostatic) | Water | 630 | 9135 | 1.5 x 38°C Rating (no visible leakage) |
| High-Pressure Seat Test | Water | 462 | 6700 | 1.1 x 38°C Rating (Rate A/B per API 598) |
| Low-Pressure Seat Test | Air / N2 | 5.5 – 7.0 | 80 – 100 | Bubble-tight |
| Welded Joint Test | Water/Helium | Full shell pressure | — | 100% inspected, no leakage |
7. Flow Characteristics (3/4″ – Class 2500)
| Parameter | Value |
|---|---|
| Flow Coefficient Cv (approx) | ~2.5 – 4.0 (typical for 3/4″ globe valve) |
| Flow Coefficient Kv (approx) | ~2.2 – 3.5 |
| Flow Characteristic | Linear / Equal Percentage (depending on trim) |
| Seat Leakage Class | Class IV (Metal Seat) per ANSI/FCI 70-2 |
| Bore Type | Full Bore / Reduced Bore (optional) |
8. Welded Bonnet Advantages
| Feature | Benefit |
|---|---|
| No Gasket | Eliminates potential leak path at body-bonnet joint |
| Threaded + Welded | Dual protection against leakage |
| Compact Design | Lighter than bolted bonnet (approx 0.2 kg less) |
| High Integrity | Suitable for high pressure, high temperature, and hazardous services |
| Maintenance | Non-repairable bonnet – but highly reliable |
| Zero Fugitive Emissions | Ideal for critical service applications |
9. Features & Applications
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Key Features:
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Welded Bonnet Construction: Threaded-in and strength-welded bonnet eliminates gasket and provides zero leakage at body-bonnet joint .
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High Pressure Capability (2500LB): Designed for extreme high-pressure applications up to 420 bar (6000 PSI) .
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Forged Body Construction: Close die forged steel provides superior strength, uniform grain flow, and absence of porosity .
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Integral Seat: Machined directly into body for maximum strength and reliability .
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API 602 Design: Meets stringent industry standards for forged steel valves .
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Excellent Throttling Control: Globe valve design provides precise flow regulation .
-
Backseat Design: Protects stem packing when valve is fully open .
-
OS&Y Design: Rising stem provides visual indication of valve position .
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High Temperature Capability: Suitable for temperatures up to 550°C with appropriate materials .
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Compact & Lightweight: Welded bonnet design reduces weight compared to bolted bonnet .
-
Multiple End Options: Available in socket weld, butt weld, or threaded connections .
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Fugitive Emission Control: Welded bonnet eliminates potential leak path, ideal for critical service .
-
-
Main Applications:
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High-Pressure Steam Systems: Power plants, boiler systems .
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Refineries & Petrochemical: Hydrocarbon processing, high-pressure fluid control .
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Oil & Gas Production: Wellhead control, high-pressure gathering systems .
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Chemical Processing: Corrosive fluid handling (with SS materials) .
-
High-Temperature Applications: Up to 550°C with alloy materials .
-
Critical Service: Where zero leakage and maximum reliability are required .
-
Instrument Connections: Small bore high-pressure isolation .
-
10. Comparison: Welded Bonnet vs. Bolted Bonnet (3/4″ Class 2500)
| Parameter | Welded Bonnet | Bolted Bonnet |
|---|---|---|
| Weight | 1.9 kg | 2.1 kg |
| Leak Path | None (welded) | Gasket (potential leak) |
| Maintenance | Non-repairable bonnet | Repairable/removable |
| Fugitive Emissions | Zero | Potential (gasket/packing) |
| Cost | Slightly lower | Slightly higher |
| Application | Critical service, high pressure | General service |
11. Ordering Information
Please specify when ordering:
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Valve size: 3/4″ (DN20)
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Pressure class: 2500LB
-
Body material: A105 / F304 / F316 / F22
-
Bonnet type: Welded Bonnet
-
End connections: SW / BW / NPT
-
Seat type: Metal (standard)
-
Disc/seat hardfacing: Stellite (optional)
-
Operation: Handwheel / Gear / Actuator
-
Special requirements: NACE, oxygen cleaning, low temperature, etc.
*Disclaimer: The above data is prepared based on common industry standards (API 602, ASME B16.34, API 598) for welded bonnet globe valves . The welded bonnet design provides maximum integrity for high-pressure and critical service applications by eliminating the body-bonnet gasket. Specific dimensions, materials, and pressure ratings may vary by manufacturer. The final technical agreement and certified drawings shall prevail.*
