Most of you are familiar with heat shrink tube Today we will introduce its production flow, which mainly consists of five procedures: compounding and pelletizing, extrusion molding, irradiation cross-linking, expansion and packaging. The details are as follows.

1. Masterbatch Pelletizing

Weigh polyolefin base materials and functional additives in accordance with the formula ratio, then blend them thoroughly. The mixed materials are fed into an extruder to produce masterbatch pellets.

2. Extrusion & Molding

Two processing methods are adopted based on product types: single-screw extrusion and injection molding.Single-screw extrusion is mainly used for tubular products, including single-wall heat shrinkable tubing, dual-wall adhesive-lined tubing, medium-wall tubing and high-voltage busbar tubing.Injection molding is applied to produce heat shrink accessories, such as end caps, sheds and finger sleeves.

3. Irradiation Cross-linking

Products after extrusion or injection molding feature linear molecular structure without shape memory property, and their overall performance needs further improvement. Irradiation cross-linking is the core procedure of the whole production. A proper cross-linking degree is essential for qualified finished products. Excessively high cross-linking degree will make expansion impossible; while insufficient cross-linking will lead to limited expansion range, potential cracking and unsatisfactory shrinkage performance.

4. Expansion

After irradiation cross-linking, the products gain shape memory effect. The materials are heated at high temperature, expanded and shaped via vacuum inflation, and then cooled down to form finished tubing.

5. Packaging

Products are wound into coils according to specifications. We can also provide customized services such as cutting and printing as requested by clients.

The above is the complete production process of heat shrinkable tubing. In case of stock shortage, we appreciate your patience. We will arrange production and delivery as soon as possible.