Test & measurement
Heatshrinks are shrinkable plastic tubes used in electrical work to insulate wires (e.g., speaker wires), providing abrasion resistance and environmental protection for stranded and solid wire conductors, connecting joints, and terminals. It can also be used to replace or bundle wire insulation, protect wires or small pieces from abrasion, and build cable entry seals that provide environmental sealing protection. Heat-shrink tubing is often composed of polyolefin, which shrinks radially (rather than longitudinally) when heated to half to one-sixth of its original diameter.
Before establishing the connection, the unshrunk tubing is put on the cable (e.g., audio cables) and then slid down to cover the joint. Silicone lubricant can be used if the fit is tight without jeopardising the heat-shrink material. The tubing is then heated in an oven or with a hot air cannon or other sources of hot gas flow to shrink it to wrap firmly around the joint. A soldering iron held close to but not touching the tube or the heat from a lighter are two convenient but less consistent methods for reducing the tube. However, we do not endorse these procedures since they can cause uneven shrinking, physical damage, and insulation failure if it becomes too hot.