Stainless steel bellows offer the best price to performance ratio of any material. Stainless steel bellows maintain their high strength capability and custom design with varying thicknesses.  BellowsTech has superior welding practices to ensure that the bellows assembly performs to our customers’ requirements. Within the stainless steel bellows family, BellowsTech offers AM350*, 316L, 347, 321 and 304L SS.

AM350 is a high-strength alloy that produces highly accurate and repeatable results with an operating range from -100°F to 800°F.  The metal is slightly magnetic and is used in non-acidic environments.

For cryogenic and non-magnetic applications, BellowsTech prefers 316L stainless steel material.  It operates from -420° up to 800°F.  316L material also offers better corrosion resistance for acidic applications.

321, 347 and 304L stainless steels are available through BellowsTech, yet are typically used for legacy, drop in replacement applications.

BellowsTech manufactures its bellows by stamping metal diaphragms, welding inside diameters to form convolutions, and finally welding the outside diameters.  This creates a very strong, yet flexible mechanical conduit compatible with liquids and gases.  Various diaphragm thickness are available as well as two-ply construction for higher pressures.

BellowsTech can build its assemblies using stainless steel from ultra-high vacuum (UHV) to positive pressures.  Whether our customer requires an actuator, volume compensator, expansion joint, or flexible seal, BellowsTech can design and manufacture to customer specifications.

With custom capabilities of size, shape, and connections, the flexibility of BellowsTech stainless steel bellows is endless.  BellowsTech can also offer designs configured from our standard sizes as well.  Over eighty standard diaphragm sizes makes finding the right fit is easy, timely, and cost-effective.  Add any type of machined flange or end piece connection to the bellows assembly in order to make installation simple.

Stainless steel bellows assembly

Specifications – Stainless Steel Bellows – PDF

Material AM350, 316L, 347, 321 or 304L SS
Thickness 0.002″ and up every 0.001″
Standard Leak Rate <1×10-9 std CC He/sec
Size Ranges
Outside Diameter 0.358″ (9.0932mm) to 22.205″ (564mm)**
Inside Diameter 0.198″ (5.029mm) to 19.921″ (505.99mm)**
Shapes Round standard. Non-Round Available; Contact Factory.
Length Up to 96 inches (244 cm)

* AM 350® is a registered trademark of Allegheny Technologies
** For other dimensional requirements, contact the factory

Examples of stainless steel bellows - high strength bellows assemblies
Typical Industries Benefits
Industrial & Semiconductor Price to Performance
Medical & Test Equipment Thickness and Multi-Ply Capability
Oil/Gas/Chemical Processing Complete Compression and 25% Extension

Stainless Steel Bellows Assembly

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