In industrial valve applications, understanding the differences between bellows-sealed globe valves and standard globe valves is crucial for selecting the solution that best meets specific needs. While both types of valves serve similar purposes in controlling fluid flow, they differ significantly in design, sealing mechanisms, and performance.
Bellows-sealed globe valves feature a metal bellows welded between the valve stem and the bonnet. This design creates an airtight seal between the fluid medium and the external atmosphere, ensuring zero leakage at the stem.
Standard globe valves utilize a conventional stuffing box (typically employing graphite or PTFE) to seal the stem. Although suitable for general operating conditions, they are prone to wear and leakage over time, particularly under extreme temperatures or high-pressure conditions.
Key Differences
Beyond structural differences, bellows-sealed globe valves and standard globe valves also differ markedly in the following areas.
| Features | Bellows-sealed globe valve | Globe valve |
| Sealing performance | Achieves true zero leakage | Minor leakage may occur after prolonged, frequent opening and closing |
| Service life | The overall service life is 2–3 times longer than that of standard globe valves. | Packing materials are wear parts; they age rapidly when exposed to high temperatures or corrosive media. |
| maintain | Significantly reduce the frequency of maintenance shutdowns. | The packing requires periodic tightening or replacement; under certain operating conditions, maintenance is necessary on a monthly basis. |
| Applicable Scenarios | Widely used in industries such as chemicals, pharmaceuticals, nuclear power, and petrochemicals; capable of withstanding temperatures up to 425°C and nominal pressures up to PN 4.0 MPa. | It is primarily used for general industrial piping and civil water supply and drainage systems with low leakage requirements, and is unsuitable for high-risk or specialized operating conditions. |
| cost | High purchase cost, but low maintenance cost. | The purchase cost is low, but maintenance costs gradually increase over time. |
When choosing between bellows-sealed globe valves and standard globe valves, consider your specific requirements: opt for bellows-sealed globe valves if the operating environment is harsh and sealing performance is critical; consider standard globe valves if cost is a primary concern and the operating environment is relatively mild.
As a professional OEM manufacturer of bellows valves—featuring an in-house foundry and fully automated precision machining lines—AIV delivers optimal, comprehensive OEM services. We leverage strong R&D capabilities, robust production and quality control systems, and advantages such as short lead times, competitive pricing, and excellent value.
AIV Bellows-Sealed Globe Valves
Product Advantages
- The valve body is manufactured using precision casting technology, which significantly improves surface finish and mechanical properties, minimizes defects such as porosity, sand holes, and cracks, and enhances the casting’s tensile strength.
- High-precision conical sealing surfaces, machined on specialized CNC equipment, ensure excellent concentricity and create a linear seal with the valve seat. The design features a “scraping effect” upon closure that automatically removes surface impurities and shears through coking deposits in the medium, ensuring reliable sealing and an extended service life for the valve disc.
- A dual-sealing design combining bellows (static seal) and packing (dynamic seal) fully meets operational sealing requirements and extends service life. This design resolves the common issue of packing wear and subsequent leakage found in traditional packed globe valves, while complying with both domestic and international sealing standards.
- All bellows undergo 100% helium leak testing, and every valve is 100% tested using intelligent inspection equipment in accordance with standards to ensure zero leakage.
- Valves sized 6 inches and above are equipped with a special mechanism that accommodates various installation angles and effectively prevents vibration during operation, providing protection and noise reduction. This is particularly effective for applications such as thermal oil pump outlets or high-velocity steam pipelines, where it prevents internal component damage caused by intense noise and vibration, effectively more than doubling the service life.
- Various disc designs can be provided based on operating conditions and medium requirements, such as throttling discs, flat soft-sealing discs, and stop-check discs.