As industries increasingly demand higher standards for valves, achieving zero leakage under rigorous operating conditions has become a widely accepted requirement. Thanks to their zero-leakage capability, robust structure, and exceptional durability, bellows-sealed gate valves are a safe and reliable choice for critical applications.
Features of Bellows-Sealed Gate Valves
- Bellows sealing element. The core component is a metal bellows; connected to the bonnet and stem via an automatic roll-welding process, it effectively ensures zero leakage at the stem.
- Dual-seal design (bellows + packing). The combination of the bellows and packing prevents leakage while delivering superior sealing performance.
- Grease injection port. Allows for direct lubrication of the stem, nut, and sleeve.
- Ergonomic handwheel. Designed for ergonomics, it ensures easier operation and a longer service life.
Differences between ANSI and DIN Bellows-Sealed Gate Valves
| Comparison dimensions | ANSI Bellow Gate Valve | DIN Bellow Gate Valve |
| Affiliation of the Standard System | ANSI bellows gate valves comply with the American National Standards system. | DIN bellows-sealed gate valves comply with the German national standard system. |
| Unit of measurement | The ANSI series exclusively utilizes Imperial units, with nominal diameters specified in inches. | The DIN series utilizes metric units, with nominal diameters designated as DN. |
| Pressure Marking | Uses the Class (LB) rating system, covering the range from Class 150 LB to Class 900 LB. | Utilizes the PN nominal pressure designation, covering the range from PN10 to PN320. |
| Suitable Scenarios | High-end industrial applications such as petrochemicals, nuclear power, and high-pressure, high-temperature steam systems. | Applications such as food processing, general chemical processing, and hot oil systems. |
Applications of Bellows Valves
The bellows gate valve is a specially designed valve featuring a sealing structure that permits unidirectional fluid flow. These valves are widely used in high-pressure and vacuum applications.
To ensure optimal performance under harsh operating conditions, manufacturers typically select materials based on the specific application; for instance, stainless steel is a common material used to fabricate the bellows.
Bellows valves are an ideal choice for applications where leakage poses a significant concern. Furthermore, they enhance personnel safety by protecting workers from exposure to hazardous gases and fumes.
AIV bellows valve adopts cone-disc design, including double sealing structure of bellows and packing. Research and development of new materials to provide excellent wear and corrosion resistance.