A cable extrusion process

Abstract

The invention discloses a cable extrusion technology, which comprises the following steps: selecting corresponding screw diameters according to cables with different specifications, carrying out warming and preheating after determining machine equipment to be intact, heating various parts of an extruder to corresponding temperatures according to the screw diameters and different materials, detecting the temperatures every two hours, and beginning to charge and start up the machine; placing a filter plate and two wire meshes in front of a machine head, and using a copper mesh and one wire mesh when impurities are excessive; ensuring that the added plastic is clean and dry during charging, starting a main engine, penetrating into a conducting wire core, starting traction, correcting a shifting core according to the trend of a rubber compound, and then measuring the wire diameter for more than six times every 30 minutes by a vernier caliper, and loading a spool for start-up when conforming to a tolerance range of the process; and simultaneously, starting a spark inspection machine, fully cooling an insulating wire core, and frequently adjusting the tension of a pay-off spool. According to the cable extrusion technology, the temperatures of different parts of the extruder are adjusted, so that the hot-shrinkage rate of the cable is reduced; the physical property is improved; and the quality of the cable is ensured.

Description

technical field [0001] The invention relates to the technical field of cables, in particular to a cable extrusion process. Background technique [0002] At present, cables play an irreplaceable role in power systems, information transmission and instrumentation systems, and can transmit power or information from one end to the other. The cable has the advantages of excellent electrical performance, good operation safety performance and thermal overload mechanical characteristics, and easy installation, operation and maintenance. In recent years, the state has paid unprecedented attention to the quality of wires and cables, and organizes relevant supervision inspections every year. The pass rate of cross-linked and cross-linked polyethylene insulated power cables is usually maintained between 75% and 85%, and unqualified Among the samples, most of them failed the thermal shrinkage test, and the thermal shrinkage performance has become the third index that is not easy to cont...

AI Technical Summary

Problems solved by technology

The thermal shrinkage performance of the cable is a value that characterizes the insulation shrinkage ratio of the polyethylene insulation of the finished cable under heating. The general inspection conditions are set at a heating temperature of 130°C for one hour. After heating and cooling, observe the shrinkage of the cable insulation. And calculate its shrinkage rate, check its thermal stress residue and change; excessive thermal stress will cause stress cracking of cross-linked insulating crystal structure, in addition to shrinkage, it may also cause partial discharge failure; thermal stress residue or uneven release It will lead to the failure of the heat shrinkage test, and its consequences may cause major safety accidents; the failure of the heat shrinkage heat will also lead to the exposure of various joints, or poor contact between the joints and the wires, causing various electrical accidents and even safety hazards. ACCIDENT

The poor temperature control of the existing cables in the extrusion process leads to unqualified thermal shrinkage performance of the cables and poor plasticization effect, which poses a huge hidden danger to the quality and safety of the cables

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