Today, quality demands on manufacturers and tailors of automotive and data cables as well as products for the aerospace sector are very complex. The products are used for different applications and need to withstand all kinds of strains. In order to guarantee flawless functionality and safety of the cables in all areas of application, manufacturers need to deliver their products with the highest quality.
The use of technologies for the production and quality assurance of cables, as well as a flexible location corporate policy is indispensable in order to be able to transfer optimized processes fast and easy to subsidiaries. For example, in the production of automotive cables, the optimal wire temperature is an important criteria for an end product of the highest quality and the further processing: from wiring harnesses for ABS and airbag systems to light systems and sensors.
Ensuring a stable conductor temperature
Many manufacturers of automotive cables work with devices for the preheating of the conductor in order to create a better adhesion of the insulation to the conductor. In order to achieve a defined adhesion of the insulation to the conductor, it is important to set the conductor temperature according to the insulating material prior to the feeding into the extruder. Only when the conductor temperature is kept constant within a small tolerance during the entire production run, it can be expected that the withdraw forces meet the specifications (Picture 3). Inadmissible scattering regarding the adhesion complicate the process considerably and often lead to claims.
For devices without a continuous measurement and control, the desired conductor temperature has to be measured manually and selectively with external sensors in order to set the power of such a preheating according to these measuring results. Environmental and production related influences have an unforeseeable effect on the obtainable conductor temperature. First of all, this includes the different temperatures of the entering copper wire (day/night/summer/winter), the changeable production speed and the gradual heating or cooling of the short circuit wheel of a preheating device. When cheaper conductor preheating devices are used, different supply voltages can also cause a change in the conductor temperature.
At this point, it is to mention that especially for the production of data cables with foamed insulation, the foam grade is largely dependent on the temperature of the preheated conductor. A constant temperature of the conductor is an important requirement for a stable foaming process.
The innovative technology of the SIKORA PREHEATER 6000 TC bypasses those risks by measuring the temperature permanently. An innovative camera captures the temperature of the conductor after the heating and controls the power of the preheating device automatically and continuously. The device is installed directly in front of the extruder and therefore, is able to react to changing environmental conditions as well as line speeds.
The result is a stable conductor temperature independent of the material. This is especially interesting for the production of automotive cables as the conductor material is not only made of copper anymore but also of aluminum.
Repeatability in all plants
For a supplier it is often of utmost importance to adapt the production to the market geographically. As the export of cable products would cause an enormous cost increase, many automotive cable manufacturers establish their plants close to the automobile plants. In order to guarantee a stable quality worldwide, the same technologies, respectively the same technical equipment should be available everywhere to specialists and operators – an automatically regulating technology at best. Industry 4.0 is the keyword in order to link production plants internationally. The PREHEATER devices of the series 6000 TC are therefore, equipped with comprehensive interfaces.
The PREHEATER 6000 TC from SIKORA can be integrated into both, new and existing production lines. The PREHEATER is able to measure continuously the temperature of the conductor and control the preheating due to the innovative IR (infrared) camera. Therefore, the PREHEATER 6000 TC works independently of external influences. This makes the devices from SIKORA the foundation for one of the most important pillars within cable production – stable process repeatability and a guarantor for a sustainable and future-oriented production.