What is a Circular Feedthrough?

As the name suggests, a ‘feedthrough’ is a piece of equipment that acts as an airtight seal, feeding wires through from an external origin into a secure internal system without releasing air or gas out into the atmosphere.

There are literally thousands of designs, models, and specifications which are determined based on the types of wires, type of connector and the relative properties of the signals being carried. Feedthroughs are constantly adapted for an ever-growing range of applications.

Outlining Circular Feedthroughs

As with the term ‘feedthrough’, a ‘circular feedthrough’, is also pretty self-explanatory. It describes a circular mechanism designed to feed wires through to a high-vacuum or ultra-high vacuum (HV/UHV) environment. In this case, the descriptor refers to the connection, which is circular rather than D-shaped. As with the wider feedthrough production market, the scope of circular feedthrough designs and types boasts a broad variety of terminations, maximum voltages, and current-carrying capacities.

Highly effective in both, HV and UHV applications, voltages and carrying capacities can be customized to fit varying scales and intensities of job.

Circular Miniature Feedthroughs

Basic Materials Making up a Circular Feedthrough

The underlying materials used in circular feedthrough construction can be tailored to meet specific end-use demands. These are primarily dictated by conductivity and insulation requirements, alongside outgassing potential. Consequently, ceramics, glass, and stainless steel remain the most common materials used in electrical feedthroughs.

Common Composition of a Circular Feedthrough

A circular feedthrough is easily identifiable in its characteristic construction. Separated into two equally significant sections – the ‘air side crimp’ and the ‘vacuum side crimp’ – a circular feedthrough must achieve properties of absolute perimeter protection.

The air side crimp contains the space to accommodate the wires which enter a collaborative configuration of the clamp, the contact, and the plug. The contact connects to the wire and marries it to the plug. The clamp is tightened and fastened to keep everything in place.

The vacuum side crimp houses the wires as they pass through the mechanism with vacuum-side contacts and a contact retainer to restrict any potential movement of the wires. As an additional movement-limiting measure, the retainer is hugged tightly by a retaining ring which adds the extra assurance that even the most minor motion will be controlled.

Added Security Through Circular Feedthroughs

Providing a highly secure gateway that can constrict and control the carrying of a range of substances, circular feedthroughs are an unavoidable aspect of any vacuum-based activity.

Take a look at the impressive portfolio of circular feedthroughs that our team at Allectra can recommend and construct for your individual needs. Our Circular Miniature feedthrough air-side connectors are EMC compliant. Or, contact us with any questions.