Heatshrink
Heatshrink tubing is crosslinked plastic tubing that shrinks in diameter when it is heated. It is used in electrical engineeering to insulate wires, conductors, connections, joints and to bundle wires together. It can also be used to provide seals through bulkheads and into junction boxes. The purpose of the heatshrink is to provide electrical insulation, abrasion resistance and environmental protection.
In operation, the expanded tubes are slipped over the component to be protected and heat applied which causes the tube to shrink tightly down onto the component. The difference between expanded and contracted size is called the expansion ratio and is how heatshrink can be classified. It can be classified further by the wall thickness of the tube and is often referred to as thin, medium and thick walled.
Silane crosslinking technology (Sioplas) offers a low cost production route for the producer of heat shrink tubing. Processing of these Sioplas materials is very straightforward on standard polyethylene and PVC extruders and crosslinking of the extruded tube is achieved through exposure to warm moist conditions. This eliminates the usual and costly electron beam irradiation process required to crosslink the polymer.
Using Sioplas technology can give products with expansion ratios of up to 4 to 1. We have made thin and thick wall heatshrink products for a number of years now. More recently however, the range has expanded to include a halogen free flame retardant grade SX738 with exceptionally low flame propagation and very low smoke evolution.
Other grades include those with track resistance for medium voltage cable joints and wrap-around products for low voltage and telecommunications applications.
Grades Available
|
Density |
Tensile |
Elongation |
Volume |
Dielctric |
Power |
Permittivity |
Data |
| SX716:CM401 Silane crosslinkable polyethylene for heatshrink wrap-around applications | |||||||
|
0.93 |
18 |
350 |
>1.0x1016 |
21 |
0.0003 |
2.0 |
|
| SX738:CM424 Flexible silane crosslinkable HFFR for heatshrink wrap-around applications | |||||||
|
1.40 |
10 |
200 |
1.0x1013 |
14 |
- |
- |
|
Please note that silane crosslinkable grades are shown as a system with a graft and a catalyst. These are normally used in the ratio of 95:5. The most common catalyst masterbatch is shown in the table but there are others available which helps us to more accurately match your property requirements and processing conditions.
