It is noteworthy that in order to ensure that the tubes can be molded to the soldering points and to the mooring of the coil head, they must be flexible. In electric motors, three types of tubes are used. They are: shrinkable polyester tube, tube with polyester weave coated with acrylic resin, and tube with fiberglass weave covered with silicone rubber. To ensure the effectiveness of some applications, such as submersible pumps, it is recommended that the cable also be chemically resistant to the pump oil. In this way, the flexible tubes have among their main functions to isolate and electrically cover the welds of the connections between the connection cable and the coil wires, as well as the other wires.
In this way, it is worth mentioning that the coupling elements are designed rigorously from specific components, elastomeric insulation and always have to be of the same thermal class of 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.