Production process of heat shrinkable pipe

Today, let's talk about the production process of heat shrinkable tubes:

Heat shrinkable tube manufacturing:

1. Masterbatch granulation;

2. Pipe extrusion;

3. Irradiation crosslinking;

4. Pipe expansion;

5. Printing packaging composition.

1. The raw materials with the set formula are batched, and then the master batch particles required for the heat shrinkable tube are produced by mixing with an internal mixer.

2. Put the above masterbatch into the mixer and extrude qualified pipes according to a certain process. During the extrusion process, the wall thickness and wall deviation of pipes have a great impact on the quality of heat shrinkable casing.

3. The above-mentioned pipes are irradiated by an electron accelerator to increase the cross-linking degree of polymer materials inside the pipes and form a network like structure. There are chemical bond phase links between the chain segments and strong interaction forces. Irradiation crosslinking process is the most critical process in the manufacture of heat shrinkable tubes. Qualified heat shrinkable tubes can be manufactured only if the irradiation crosslinking degree is appropriate. If the irradiation crosslinking degree is too large, the tubes cannot be expanded. The industry commonly known as "irradiation is dead". If the crosslinking is too small, the tubes can not be expanded, or can not be expanded to a larger multiple, which is easy to crack. Moreover, the shrinkage force of the heat shrinkable tubes manufactured is not enough, and the shrinkage effect is not good. Therefore, it is necessary to formulate appropriate irradiation process parameters for each product in order to manufacture qualified heat shrinkable tubes.

4. After irradiation crosslinking, the diameter of the pipe can be enlarged by preheating to a higher temperature and expanding by external force, and then it can be rapidly cooled to normal temperature, so that the shape of the expanded pipe will be finalized. The main principle of this process is that the activity of the high molecular weight chain segment of the pipe after irradiation crosslinking is greatly related to the temperature. Within a certain high temperature range, the resistance of the chain segment to stretch and bend is very small, and the whole pipe is like an elastic net, which can be stretched by external force, so when heated to this temperature range, the pipe can be easily expanded. When the temperature drops rapidly, usually around room temperature, this activation phenomenon will be lost. The resistance of the chain segment to stretch and bend is very large, and the internal stress of retraction is not enough to overcome this resistance, so it will maintain the expanded shape in the natural state.

5. After the heat shrinkable casing is produced, it can be sold after pipe cutting and packaging printing.

This production process greatly reduces the investment cost, energy consumption and production cost, and improves the production efficiency and product quality. The products produced have high mechanical strength, long service life, corrosion resistance, aging resistance and environmental pressure resistance.