DN25-PN25 Close Die Forged Plunger Valves
Description
TECHNICAL DATA SHEET
Product Name: DN25 PN25 Close Die Forged Plunger Valve
Model/Specification: DN25-PN25-PLUNGER
Valve Type: Plunger Valve (Piston-Type Stop Valve)
Connection Type: Flanged (RF) / Threaded (NPT) / Socket Weld / Butt Weld User specified
1. Basic Design Parameters
| Parameter | Standard/Specification |
|---|---|
| Size | DN25 (1 inch) |
| Pressure Class | PN25 (25 bar / 360 PSI) |
| Body Material | Forged Carbon Steel (A105) / Forged Stainless Steel (A182 F304/F316) User specified |
| Manufacturing Process | Close Die Forged (Precision Forging) |
| Design Standard | DIN 3356 / EN 13709 / ASME B16.34 (adaptable) |
| End Connection Standard | EN 1092-1 (Flanged) / ASME B1.20.1 (NPT) / ASME B16.11 (SW) / ASME B16.25 (BW) |
| Face to Face Standard | EN 558-1 / DIN 3202 F1 (for flanged) |
| Test & Inspection Std. | EN 12266-1 / API 598 |
| Leakage Class | Zero leakage (soft seal) |
2. Technical Specifications
| Parameter | Details |
|---|---|
| Valve Type | Plunger Valve (Piston Valve) – Guided plunger design |
| Bonnet Type | Bolted Bonnet |
| Stem Type | Outside Screw and Yoke (OS&Y), Rising Stem |
| Plunger Type | Polished cylindrical plunger, one-piece forged |
| Sealing Principle | Elastic sealing rings (graphite/PTFE) compressed by plunger – metal-to-soft seal |
| Sealing Rings | Two-piece set (upper & lower) for positive shut-off |
| Applicable Media | Steam, Hot Water, Oil, Gas, Corrosive Fluids (depending on material) |
| Temperature Range | -29°C to +300°C (with PTFE rings) / up to 450°C (with flexible graphite) |
| Operation | Handwheel (standard) / Gearbox / Actuator |
3. Material of Construction (Recommended – Carbon Steel)
| Part Name | Material | Standard/Grade |
|---|---|---|
| Body | Forged Carbon Steel | ASTM A105 |
| Bonnet | Forged Carbon Steel | ASTM A105 |
| Plunger | Stainless Steel (Hardened) | ASTM A276 420 / A182 F304 (Chrome plated optional) |
| Sealing Rings | Flexible Graphite / PTFE | Graphite for high temp, PTFE for chemical service |
| Stem | Stainless Steel | ASTM A182 F6a (13Cr) / A276 420 |
| Gland Packing | Flexible Graphite / PTFE | As backup seal |
| Bonnet Gasket | Spiral Wound | Stainless Steel + Graphite |
| Stem Nut | Aluminum Bronze | C95400 / CuAl10Fe3 |
| Body Bolts/Nuts | Alloy Steel | ASTM A193 B7 / A194 2H (for CS) or A193 B8 / A194 8 (for SS) |
| Handwheel | Malleable Iron / Carbon Steel | A197 / A216 WCB |
*For Stainless Steel version (A182 F304/F316), bolting changes to B8/8, body/bonnet to SS.*
4. Main Dimensions & Connection Details
*Note: Dimensions for Flanged Ends (RF) according to EN 1092-1 and EN 558-1. Other end connections vary.*
4.1 End-to-End Dimensions (Face-to-Face)
| Size | PN Rating | L (mm) | H (approx. mm) | W (Handwheel mm) | Weight (approx. kg) |
|---|---|---|---|---|---|
| DN25 | PN25 | 160 | ~180 | 125 | ~4.5 |
4.2 Flange Details (Per EN 1092-1 – Type 11 / PN25)
| Parameter | DN25 Flange |
|---|---|
| Flange Outside Diameter (D) | 115 mm |
| Bolt Circle Diameter (PCD / k) | 85 mm |
| Number of Bolt Holes | 4 |
| Bolt Hole Diameter (d2) | 14 mm |
| Bolt Thread Size | M12 |
| Raised Face Height | 2 mm |
| Flange Thickness (C) | 16 mm |
4.3 End Preparation (Alternative Connections)
| Connection Type | Standard | Details |
|---|---|---|
| Threaded (NPT) | ASME B1.20.1 | 1″ NPT Female |
| Socket Weld (SW) | ASME B16.11 | 1″ Socket Weld per standard |
| Butt Weld (BW) | ASME B16.25 | Bevel prepared ends |
5. Pressure-Temperature Rating
*Material Group: Carbon Steel (A105) or Stainless Steel (F304/F316) – Sealing rings limit temperature.*
| Temperature (°C) | Max. Working Pressure (bar) | Notes |
|---|---|---|
| -29 to 120 | 25 | Full rating (PTFE rings) |
| 150 | 24 | |
| 200 | 23 | (Graphite rings) |
| 250 | 22 | (Graphite rings) |
| 300 | 20 | (Graphite rings) |
| 350 | 18 | (Graphite rings – high temp) |
| 400 | 16 | (Graphite rings) |
Note: With PTFE rings, max temperature 200°C. With graphite rings, max 450°C (but PN rating derated at higher temps).
6. Test Pressure (EN 12266-1 / API 598)
| Test Type | Medium | Pressure (bar) | Acceptance Criteria |
|---|---|---|---|
| Shell Test (Hydrostatic) | Water | 38 | 1.5 x PN (no visible leakage) |
| Seat Test (High Pressure) | Water | 27.5 | 1.1 x PN (zero leakage) |
| Seat Test (Low Pressure) | Air / N2 | 5.5 – 6 | Bubble-tight |
7. Features & Applications
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Key Features:
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Zero Leakage Design: Elastic sealing rings compressed by the polished plunger ensure bubble-tight shut-off, exceeding metal-seated valve performance .
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Close Die Forged Body: Provides superior strength, uniform grain flow, and absence of porosity – ideal for demanding service .
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Self-Adjusting Seals: The sealing rings compensate for wear and thermal variations, maintaining a tight seal over extended life .
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Easy Maintenance: Sealing rings can be replaced without removing the valve body from the pipeline (with top-entry bonnet) .
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Excellent Throttling Capability: The plunger design allows for smooth flow control with minimal erosion .
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Double Seal Protection: Two independent sealing rings provide redundancy .
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Corrosion & Wear Resistance: Hardened stainless steel plunger resists scratching and corrosion .
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Backseat Design: Protects stem packing when valve fully open .
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OS&Y Design: Visual indication of valve position .
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Main Applications:
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Steam Systems: Steam distribution, boiler blowdown, tracer lines .
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Thermal Oil / Heat Transfer Fluids: High-temperature liquid services .
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Chemical Processing: Handling corrosive fluids with PTFE sealing rings .
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Water & Wastewater: Isolation and control where zero leakage is required .
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Oil & Gas: Light hydrocarbon services .
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General Industrial Piping: Reliable shut-off for gases and liquids .
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Disclaimer: The above data is prepared based on common industry standards (DIN/EN) for forged plunger valves. Specific dimensions, materials, and pressure ratings may vary by manufacturer. The final technical agreement and certified drawings shall prevail.