Composition and Classification of Bellows-Sealed Globe Valves

As a type of industrial valve, bellows-sealed globe valves are highly favored in sectors such as the chemical, oil and gas, and petrochemical industries. They are used to regulate and control the flow of fluids, gases, and other media within pipelines or systems. Due to their unique design, they are frequently employed in applications involving the transport of corrosive or toxic media.

Components of Bellows-Sealed Globe Valves

A bellows-sealed globe valve consists of a valve body, disc, stem, bonnet, bellows seal assembly, and packing. The valve body houses the disc, which controls the flow of the medium. The stem connects the disc to the actuator or handwheel, enabling the opening and closing of the valve. The bonnet encloses the stem and packing, while the bellows seal structure serves to prevent leakage.

Differences Between Standard Globe Valves and Bellows-Sealed Globe Valves

Both standard globe valves and bellows-sealed globe valves fall under the category of globe valves. The primary distinction is that the bellows-sealed version incorporates a bellows sealing structure. The bellows seal is a flexible metal component that provides a leak-proof seal while protecting the stem from corrosion; this makes bellows-sealed globe valves better suited for applications demanding high performance and reliability.

Types of Bellows-Sealed Globe Valves

Y-Pattern Bellows Globe Valve

The Y-pattern bellows globe valve is a high-performance, positive-sealing valve that combines a Y-shaped straight-through flow path with a metal bellows seal. The Y-shaped angled flow path allows the fluid to pass in a nearly straight line, reducing flow resistance by 30% to 50% compared to standard globe valves, while also offering a short opening/closing stroke and ease of operation.

ANSI Standard Bellows Globe Valve

The ANSI standard bellows globe valve is an industrial-grade shut-off valve designed in strict accordance with standards such as ANSI/ASME B16.34. It utilizes an all-welded metal bellows to create a sealing barrier, achieving zero external stem leakage; combined with redundant packing to form a dual-protection system, it fully complies with ISO 15848 low-leakage requirements. The valve body is primarily manufactured using precision investment casting. The stem undergoes nitriding for wear and seizure resistance, while the sealing surfaces are hard-faced with cemented carbide to resist erosion; the valve is suitable for steam as well as flammable, explosive, and toxic hazardous media.

Forged Steel Bellows Globe Valve

The core component of the bellows globe valve is the metal bellows, which connects the bonnet and the stem via an automated roll-welding process, ensuring zero leakage at the stem. It features a dual-sealing design (bellows plus packing); the bellows and packing work in tandem to effectively prevent leakage and provide superior sealing performance. Thanks to its conical and streamlined structural design, the valve disc offers reliable sealing and an extended service life.

Angle-Pattern Bellows Globe Valve

The angle-pattern bellows globe valve is a specialized sealing valve featuring a right-angle flow path. It utilizes a metal bellows as the primary sealing element—replacing traditional packing to achieve zero stem leakage—and incorporates a dual-sealing structure (bellows plus packing) that fully complies with international zero-leakage standards. The 90-degree angle design allows for a change in flow direction without the need for additional elbows, significantly saving installation space while offering lower flow resistance and facilitating easier piping layout.

DIN Standard Bellows Globe Valve

The valve body features a new structural design produced using the German resin-coated sand casting process; this significantly improves surface finish and mechanical properties while minimizing defects such as porosity, sand holes, and cracks.

In the closed position, the conical sealing surface—which possesses a scraping action—automatically clears away surface impurities, ensuring reliable sealing and extending the service life of the valve disc. Under the same closing force, the conical disc generates higher specific sealing pressure, making the valve easier to close while delivering superior sealing performance.

AlV bellows valves utilize a conical disc design and a dual-sealing structure comprising both bellows and packing. Through the development of new materials, the products offer exceptional wear and corrosion resistance. We employ advanced hydraulic simulation software to optimize the valve’s flow path design, helping customers achieve safe operation, improved energy efficiency, and reduced operating costs.