Braiding & Shielding
The braiding and shielding for a cable determine the conditions it can withstand: low temperature, high-temperature, differing atmospheric pressures, even outer space. Calmont works closely with your team to determine your product’s requirements – such as level of EMI, flexibility, and angled applications to improve flexibility – and designs custom braiding and shielding to maximize efficiency and the life of the product.
Braiding is not a new technology. Braiding machines were invented in the 1850s to manufacture shoelaces. Fifty years later, as electricity became available to customers far and wide, engineers realized that they needed braiding for electrical wires. The machines originally used to manufacture shoelaces were converted to work on braiding for insulation.
A shield is a conducting envelope that encloses a wire or cable and may perform many functions – some electrical, some mechanical. The primary electrical function is to prevent interference with surrounding wires or electrical components by confining the electrical signal within the wire or cable. This protection also guards your wire or cable from outside electrical signals and interference. Medical and aerospace applications are particularly susceptible to outside interference. Mechanically, shields are used to protect the wire from physical damage, like abrasion.
Types of shields
Round Wire: Calmont shields can be made of bare copper, tinned copper, or any number of alloys. Most of our wire shields are made from 32-44 AWG wires, but for custom designs Calmont can use wire as large as 28 AWG.
Braided shield: A wire braid is formed the same way as a textile braid, with an overlapping, interwoven pattern. Calmont can design the angle and density of the braid to meet the flexibility coverage requirements of the application.
Spiral shield: A spiral shield is composed of wire strands that are applied helically in one direction around a wire or cable. The advantage to a spiral shield is its flexibility compared to a braided shield. However, they remain less effective at containing high frequencies. For additional coverage and protection, Calmont can apply a reverse spiral shield – layered on top, instead of interwoven – of the original spiral shield running in the opposite direction.
Foil Tape: Copper or Aluminum tape is often used as a shield because of its economic advantages over all forms of wire shielding. While not quite as flexible as a wire braid or spiral shield, tape shields have excellent electrical shielding characteristics and work extremely well for many applications.
If you have any questions about our cable or wire products, or if you’re looking for a quote, contact us at (800) 905-7161 or through our online form.