DN100-PN25 Bellow Seal Globe Valve
Description
Technical Data Sheet (English Version)
Product: Bellows Seal Globe Valve
Size / Rating: DN100 – PN25 – RF (Flanged)
1. General Description
This bellows seal globe valve features an advanced double sealing system consisting of a metal bellows and a back‑up packing, completely eliminating stem leakage. It is the ideal choice for critical applications such as steam, thermal oil, toxic or hazardous fluids, and valuable media. With its DN100 size, it meets the demands of high‑flow process pipelines and is widely used in petrochemical, power, pharmaceutical, and metallurgical industries as a direct upgrade from conventional packed globe valves.
2. Basic Specifications
| Parameter | Specification |
|---|---|
| Size | DN100 (4”) |
| Pressure Rating | PN25 (Class 150) |
| Design Type | Bellows Seal Globe Valve |
| End Connections | Flanged (RF, Raised Face) |
| Flange Standard | EN 1092-1 / ASME B16.5 (optional) |
| Temperature Range | -29°C up to +425°C (depending on bellows & packing material) |
| Media | Steam, hot water, thermal oil, toxic gases, corrosive fluids |
3. Material Specification
| No. | Part Name | Standard Material | Upgrade Option |
|---|---|---|---|
| 1 | Body | WCB (CS) / CF8 (SS304) | CF8M (SS316) / WC6 (Alloy Steel) |
| 2 | Disc | 2Cr13 / 304 SS | 316L SS / Stellite hardfaced |
| 3 | Stem | 2Cr13 / 304 SS | 17-4PH / Inconel |
| 4 | Bellows Assembly | 304 / 316L SS (multi‑ply) | Inconel 625 / Hastelloy |
| 5 | Packing | Flexible Graphite | High‑temperature graphite + anti‑extrusion rings |
| 6 | Bonnet | Same as body | Same as body |
| 7 | Operator | Handwheel with gearbox (standard) | Electric / Pneumatic actuator (optional) |
4. Key Features
4.1 Zero Leakage Bellows Seal
-
Double sealing safety – The bellows + packing configuration provides a primary seal (bellows) that eliminates stem leakage, plus a secondary packing seal for added protection.
-
Long fatigue life – Bellows are tested for over 10,000 cycles to ensure reliable performance under frequent operation.
-
Environmental compliance – Achieves zero stem leakage, meeting ISO 15848 fugitive emission standards for safer, more environmentally friendly operation.
4.2 Large‑Diameter Globe Valve Advantages
-
Flow direction “low in, high out” – Media enters below the disc, ensuring tight shut‑off as system pressure assists sealing.
-
Throttling capability – Suitable for both isolation and flow regulation.
-
Gearbox operation – Standard gear operator reduces handwheel torque for easy operation on DN100 and larger sizes.
-
Easy maintenance – Top‑entry design allows internal components to be serviced without removing the valve from the pipeline.
4.3 Flanged Connection
-
Flanged ends provide easy installation and removal, suitable for medium‑to‑high pressure systems.
-
Raised face (RF) sealing surface with spiral wound gasket ensures reliable sealing performance.
5. Testing & Standards
| Test / Standard | Reference |
|---|---|
| Design & Manufacture | BS 1873 / ASME B16.34 |
| Flange Standards | EN 1092-1 / ASME B16.5 |
| Pressure Testing | API 598 / ISO 5208 |
| Shell Test | 1.5 × PN25 (3.75 MPa) |
| Seat Leakage Test | 1.1 × PN25 (2.75 MPa) |
| Bellows Endurance Test | 10,000 cycles with zero leakage |
| Fugitive Emission (optional) | ISO 15848‑1 / TA‑Luft |
6. Installation & Maintenance Notes
-
Flow direction – Globe valves are directional. Install according to the flow arrow on the body (flow under the disc).
-
Flange installation – Use appropriate gaskets (spiral wound recommended). Tighten bolts evenly in a cross pattern to avoid flange leakage.
-
Operating torque – For DN100 with gearbox, do not use extensions or excessive force. When closing, turn the handwheel until resistance is felt; for high‑temperature service, re‑tighten slightly after the system reaches operating temperature.
-
Periodic inspection – Although the bellows is designed for long life, regularly inspect the packing area for any signs of leakage and check gearbox lubrication.
7. Approximate Dimensions (for reference)
| Dimension | Value (mm) |
|---|---|
| Face‑to‑Face Length (L) | ~350 (flange to flange) |
| Flange Outer Diameter | Per EN 1092-1 / ASME B16.5 |
| Flange Bolt Circle | Per applicable flange standard |
| Overall Height (H) | ~650 (including gearbox) |
| Handwheel / Gearbox Diameter | ~300 |
Note: Final dimensions are subject to the specific design; certified GA drawings should be referenced for engineering purposes.
Remarks:
-
This valve is recommended for steam, thermal oil, toxic, and valuable media. Material selection should be verified based on actual service conditions.
-
For actuated versions (electric or pneumatic), an ISO 5211 top mounting flange is available upon request.
