The auxiliary equipment of a plastic extrusion unit mainly includes a wire feeding device, a straightening device, a preheating device, a cooling device, a traction device, a meter counter, a spark tester, and a take-up device. The auxiliary equipment selected varies depending on the application of the extrusion unit; for example, it may also include a cutter, a dryer, and a printing device.
One of the most common types of waste products in plastic extrusion is eccentricity, and various types of bending of the wire core are one of the important causes of insulation eccentricity. In sheath extrusion, scratches on the sheath surface are often caused by bending of the cable core. Therefore, a straightening device is essential in various extrusion units. The main types of straightening devices include: roller type (divided into horizontal and vertical types); pulley type (divided into single pulley and pulley block types); winch type, which combines multiple functions such as driving, straightening, and stabilizing tension; and pressure roller type (divided into horizontal and vertical types), etc.
