Insulation and Screening of High Frequency Coaxial Cables

Depending on its final use, the construction of a cable can be very complex and may even require multiple processing phases on the same conductor; as in the case of taping process, where covering the conductor with different materials gives the final performances a different effect.

An effective example of this aspect can be experienced on coaxial cables for high frequency data transmission: a dielectric insulation is first obtained on the conductor using expanded PTFE tape and then its screening using silver-plated copper tape.

In the first step, through the careful application of various layers of expanded PTFE tape, the necessary dielectric insulation is obtained, which provides the cable with different characteristics depending on the thicknesses and densities of the tapes used. The importance of the precision of the taping machine used should not be overlooked, to ensure total uniformity and perfect concentricity of the cable after each application of tape, verifiable through process control and monitoring systems that certify the quality of the cable obtained.

In the subsequent screening process, the correct deposition of the silver-plated copper tape can make the difference in terms of the speed of the transmitted signal: for this reason, the specific WTM taping machine has been designed paying maximum attention to the specificity of this type of cable. On the one hand, optimizing the precision of the tape deposition, on the other, focusing on the control of the tension of the tape itself, to ensure the tight tolerances on the dimensions; all the aspects mentioned above make this machine extremely sophisticated and refined.

In this video, we show how our horizontal taping lines perform both the steps described: different construction phases but both necessary for the production of a high-frequency coaxial cable:

• the creation of the dielectric insulating layer, coating the metal core with expanded PTFE and
• the subsequent screening, applying silver-plated copper tape to the cable insulated in the previous step.

The difference between the two taping processes is evident from the notable differences between the two machines, each characterized by specificities and added values that our team will be happy to explain to you.

Here is the video, and don't hesitate to contact us!