Conductive PTFE hose modified with conductive filler is often used for electrical control in high-temperature environments, especially the protective sleeve of aircraft engine partially shielded cables and cable bundles, which can shield the magnetic field generated by the current through the cable The role of access to the ground network in the cable and along with this layer. However, the single-layer conductive PTFE tube is potentially dangerous as a protective sleeve for shielded cables and cable bundles due to its surface conductivity. It is best to design an insulating layer on the outer layer of the conductive double-layer PTFE tube to electrically isolate the PTFE conductive layer from the surrounding environment, so as to ensure the power transmission and protect the cable from damage.
Conductive PTFE hose modified with conductive filler is often used for electrical control in high-temperature environments, especially the protective sleeve of aircraft engine partially shielded cables and cable bundles, which can shield the magnetic field generated by the current through the cable The role of access to the ground network in the cable and along with this layer. However, the single-layer conductive PTFE tube is potentially dangerous as a protective sleeve for shielded cables and cable bundles due to its surface conductivity. It is best to design an insulating layer on the outer layer of the conductive double-layer PTFE tube to electrically isolate the PTFE conductive anti-static liners from the surrounding environment, so as to ensure the power transmission and protect the cable from damage.
At present, most of the double-layer PTFE tubes with outer insulation and inner conductivity on the market are prepared by referring to the paste extrusion process of traditional single-layer PTFE tubes. The traditional paste extrusion method is specified as follows: 1. Add an organic solvent as an extrusion auxiliary to the dispersed PTFE powder to obtain a paste, which is preformed into a cylindrical shape to obtain a tube blank, Put the tube blank in an extruder, pressurize by a pressure head, and extrude it into a tube shape through a die; 2. Afterward, remove the extrusion auxiliary by heating, etc., and fire to obtain a predetermined tube. When using this method for double-layer PTFE pipes, a double-layer pipe can be obtained by performing a blank and then extrusion molding, or a PTFE single-layer pipe is manufactured first, and then several single-layer pipes are processed. This method is not easy to control in actual operation, and black spots are prone to appear on the outer surface of the tube, which seriously affects the product quality, and the yield rate is low.
After many times of debugging, our company has made improvements in the original production process. The PTFE paste extruder machine has successfully produced a double-layer PTFE hose (the inner layer is carbon, and the outer layer is PTFE dispersion). According to the number of layers of the PTFE tube, the original one-time pre-forming is changed to multiple pre-forming. After one-time extrusion, drying, sintering, and shaping, a multilayer PTFE tube is formed; There is no mutual contamination between them, which improves the product quality, guarantees the yield rate, and the process is controllable; because it is a single extrusion molding, there will be no problem of blocking the pipe with composite scraps after molding.
Post time: Jun-30-2020