Stainless steel bellows are designed to withstand high pressure, high temperatures, or critical media.


Choosing the correct material for your metal bellows is essential. Non-ferrous metals, for example, are suitable for many sensing and actuation applications, but cannot be used for the handling of aggressive chemicals or production lines that place a very high emphasis on cleanliness, such as the food industry. Also for applications in vacuum chambers, such as vacuum valves, pumps or vacuum interrupters, the best solution is to use one of our high-quality stainless steel bellows.


Where hydroformed stainless steel bellows are used


Mera Bellows produces stainless steel bellows for international customers, operating in industries such as automotive, aviation, or energy distribution. They are used, for example, as volume compensators, pressure- and temperature sensors, or flexible connectors (expansion joints). For instance, in the field of renewable energies, such as solar thermal systems, Mera Bellows stainless steel bellows are widely implemented to absorb vibrations and thermal expansion between the solar panels. Used as metal bellows couplings, torsional (turning) moments can be compensated. Ensuring stability for this application, the length of bellows is of particular interest in the development phase to avoid torsional buckling.

Hydroformed stainless steel bellows are furthermore used to seal problematic media. For example, in the field of bellows-sealed valves, such as gate valves, safety valves, or check valves. For these applications, a hermetic stem sealing is needed that simultaneously compensates the relative movements between the valve plate and housing that are caused by opening and closing of the valve system. Our stainless steel precision bellows or those made of nickel based alloys (e.g. Monel400) are 100% leak tested (absolute tightness), are media resistant and persuasive under many load cycles. They protect the spindle while being resistant to corrosion – used for higher pressure and extreme temperature requirements, often in a double-walled design.


The advantages of Mera Bellows stainless steel bellows


We have a long-standing expertise in the manufacturing of hydraulically formed seamless stainless steel bellows. Stainless steel bellows are made in the same way as other high-quality Mera Bellows products. Generally, we manufacture deep-drawn seamless tubes first before using a special hydroforming tool. This cassette is customized for every bellows and is responsible for the amount and depth of convolutions, having profound effects on how the metal bellows will perform in terms of stroke, pressure capabilities, spring rate, and temperature response.

The production method of using deep-drawn tubes for hydroforming increases the design possibilities. It allows to fabricate stainless steel bellows with closed ends. The bellows’ bottom can be supplied in a customized shape which may, in many cases, lower the installation expenses further. It often allows to implement the metal bellows into applications without the complicated and expensive soldering or welding of flanges, e.g. for force transmission. Another advantage of seamless steel bellows is that in comparison to welded constructions they have lower variances and thus a more stable performance. As metal bellows have key positions in many systems, bursting of them would be disastrous. Beside of danger, a replacement would be extremely cost-intensive. In the field of medium voltage energy distribution for example, vacuum circuit breakers contain a stainless steel bellows that allows movements of the contact while maintaining vacuum inside the interrupter. For such vacuum applications, also the surface is of particular importance in order to guarantee a secure performance. Using seamless stainless steel bellows is lowering the probability of contamination around the weld-seam. They impress as ultra-clean, safe and long-lasting components.

Mera Bellows is a long-established metal bellows manufacturer – in Business since 1956. After the acquisition by a German group in 2000, quality standards are continuously improving, while being able to offer competitive prices. A modern large-scale production was opened in 2007. The company is certificated according to ISO 9001 and ISO 14001. A highly-experienced Quality Manager is monitoring all manufacturing steps. FMEA, MSA, PPAP, SPC, 5S and other core tools of ISO TS-16949 have been implemented during the last years in order to meet all our customer’s expectations. If you are in need of hydroformed stainless steel precision bellows you can always rely on Mera Bellows as an experienced manufacturer.