1. about the heat shrinkable tubethe heat shrinkable tube is a tube specially made of polyolefin material which will shrink when heated. the surface layer is made of high-quality soft chemically cross-linked polyolefin raw material and the inner layer of hot sol composite production and processing. the surface material has the corrosion resistance on insulating layer, wear resistance and other characteristics, and the inner layer has low melting point, moisture-proof sealing and high adhesion and other advantages.the heat shrinkable tube has the functions of high temperature shrinkage, soft flame retardancy, and anti-corrosion of the insulating layer. as the temperature changes from low to high, the fiber material will experience the state of laminated glass—high elastic state. the properties of fiber material in the laminated glass state are close to those of plastic, and the properties of it in the high elastic state are close to those of vulcanized rubber. the commonly used raw materials of heat shrinkable tubes are in the state of laminated glass at room temperature, and become highly elastic after heating.so does electrical tape shrink when heated? during manufacture, the heat shrinkable tube is heated to a high elastic state, the load is released to make it expand, and it is rapidly cooled while maintaining the expanded state, so that it enters the state of laminated glass, and this state is fixed. as soon as it is heated during application, it becomes highly elastic, but when the load is gone, it shrinks.2. how to choose the heat shrinkable tube?(1) the heat shrinkable tube and the heating equipment do not need to be too close together. be sure to pay attention to the distance between the fire and the heat shrinkable tube, that is, move 4 to 5cm evenly. when heating up, there is no need to exceed the high temperature resistance limit of the heat shrinkable tube. for the heat shrinkable tube, if the temperature exceeds the high temperature resistance limit, it will make people's goods "melt" and return to the original state.(2) select a suitable special heating tool. in the case of heating and baking, the outer flame of the flame and the surface of the heat shrinkable tube form an included angle of 45°. be sure to pay attention to the reciprocating movement to ensure the heat shrinkable tube is heated as a whole. gradually move it from one end to the other end, and the heating should be uniform to prevent air bubbles, so as to ensure the appearance design of the heat shrinkable tube after being folded. and unfold and adjust it after cooling.(3) the heat shrinkable tube including