Basic Requirements of Cable Extrusion Process

Cable Sheathing

The surface of the plastic extruded wire jacketing should be smooth and round. There should be no defects such as bubbles, inclusions and trachoma visible to the naked eye on the cross section of the wire jacket.

The extruded jacket layer should be continuous and complete, and the thickness of the extruded cable sheathing should meet the nominal thickness specified by the process. Meanwhile nominal thickness of the sheath should meet the requirements of various national standards for wires and cables.

Technology data

Screw diameter:   Φ45mm   Φ75mm

Screw L/D ratio:    25：1

Extrusion output:  PVC：200±5%kg/h

Core diameter before extrusion:   Φ1-Φ10mm

During cable extrusion process, the outer cable sheathing surface of the plastic wire and cable must be printed with permanent identification marks such as the manufacturer's name, model, specifications, manufacturing length, and manufacturing year. . The printing method of the identification mark can be embossed on the cable sheathing by the word wheel block, or printed on the surface of the sheath by the ribbon block, or printed by ink. The printing should be clear and continuous.

Cable sheathing directly squeezed on a smooth surface, such as a single-core cable, without plastic film wrapping, the average thickness of the cable sheath should not be less than the nominal value, and the minimum thickness measured at any point should not be less than the nominal value 85%-0.1mm.

The key of extrusion machine is the extruder screw.

1. The extruder in the absorption of advanced technology and design ideas from local and abroad, it has many advantages, avoids disadvantages of the design. The frame adopts the integral structure, and there is no need to install the motor separately. It is made of large diameter rectangular tube welding machine, easy to install, stable and reliable structure.

2.Screw structure refers to the most advanced foreign screw structure, with large extrusion volume and good plasticizing effect; Screw material using high quality materials, professional screw factory processing, 3D CNC machine processing, with high precision, high linearity;

3. Screw, material cylinder by two times nitrification process, nitrification time >100 hours, nitrification depth >0.5 mm, with long service life. The gearbox adopts 250 hard tooth gearbox, and widens the tooth face of the gearbox to improve the strength and operation stability of the gearbox. Increase the type of screw thrust bearing, that isto increase the safety factor of equipment use and improve the stability of screw running speed, ensure the uniformity of screw discharge, so as to ensure the uniformity of cable extrusion thickness.

Main Technical data