It should be noted that the coupling components are accurately designed from specific components, elastomeric insulation and must always be of the same thermal class as the motor. These components have a high electrical resistance, which is coupled with the appropriate flexibility, so that simple handling can occur in the course of processes of extreme importance, such as manufacturing, maintenance and installation of the motor.
That is, in order to ensure that the tubes used throughout the bonding process can be molded to the weld points and to the mooring of the bobbin head, they must be flexible. In the case of electric motors, three different types of tubes are used, which consist of the shrinkable polyester tube, polyester weave tube covered with acrylic resin, and tube with glass fiber weft covered with silicone rubber. In order to guarantee the effectiveness of some applications, it is indicated that the cable is also chemically resistant to the pump oil. Therefore, the flexible tubes have among their main functions electrically insulating and covering the welds of the connections between the connecting cable and the coil wires, as well as the other wires.