The aerospace industry demands products that withstand rigorous conditions while maintaining high reliability — because failure is not an option. In addition, aerospace engineers often require extensive support from manufacturers (in the form of analysis and product testing) because many parts are designed specifically for these applications. Finally, all components used in NASA, U.S. military, or FAA applications, regardless of size, must meet stringent requirements.

Rising to these challenges are miniature metal bellows from Servometer/PMG LLC, Cedar Grove, N.J. These sometimes miniscule parts are particularly suitable for aerospace applications because they are far lighter than comparable machined components. In addition, the miniature metal bellows can be made as small as 0.5 mm in diameter, to fit into the smallest of design envelopes.

Mechanical redundancy for electronics

Increasingly, emerging products of all industries are being governed by digital electronic systems … aerospace included. Metal bellows add mechanical redundancy to electrically based aerospace components to ensure safety and reliability. A variety of devices — from flight controls to breathing apparatus — incorporate mechanical bellows technology, because it is unaffected by electrical signal spikes or EMPs. In short, Servometer bellows and applications are mechanical alternatives to digital platforms. A digital application will fail if the electricity fails; in contrast, bellows applications will fail only if the laws of physics fail.

Information provided by engineers Paul Hazlitt and Brent Caldwell of Servometer/PMG LLC. For more technical information, call (973) 785-4630 or visit servometer.com.

Bellows for speed detection

Metal bellows are used in pressure sensing for speed detection. For this application, leak-tight electrodeposited nickel bellows are made with very thin walls — on the order of 0.013 mm — to create sensitive bellows and assemblies capable of responding to minute changes in pressure, even with small effective diameters.

Bellows for communication devices

New communications technologies require careful management of signals in high-frequency connections. Servometer gold-plated bellows contacts are used in these devices because they exhibit low dB losses, plus flexibility and inherent reliability.

In addition, many aerospace communication technologies use convoluted Servometer electroforms as flexible, low-loss waveguides.