Heat fusion technology has existed for many years. Over time and with technological advancements, ordinary heat fusion joints have evolved into a more convenient electro-thermal fusion jointing technology. Heat fusion bonding is essentially a physical process. After heating the heat shrink sleeve for a certain period of time, the tightly packed molecular chains melt. Under the action of stable pressure, the two fittings are connected and fixed, and bonding pressure is established at the fusion point. However, due to the bonding pressure, the molten molecular chains reconnect at the cooling temperature, and the two components close together. In other words, temperature, joint pressure, and heating time are three very important factors in heat fusion bonding.