General Purpose UL Heat Shrink Tubing UL 224 VW1/CSA Flexible Flame Retarded Polyolefin Heat Shrinkable Tubing SPUL heat shrink is a flexible flame retarded heat shrink tubing fully marked to UL (UL 224 VW1) and CSA requirements. SPUL Heat Shrink Tubing - Specification 135°C Flexible Heat Shrink Flame Retarded Tubing UL/CSA approved. Shrink Ratio: 2:1. Operating Temperature: -55°C to 135°C. Shrink Temperature : 100°C. Heat shrink colours - black. Thorne & Derrick are the largest UK distributor of heat shrink tubings and sleevings including 3M, Panduit, Hellermann Tyton, DSG Canusa, Shrinktek and Thomas & Betts. Stock lines include thin, medium and thick wall adhesive lined heat shrink sleeves and moulded shapes (heat shrink cable caps, cable breakouts and cable boots) - insulate, seal, protect with heat shrinkable tubing. Heat Shrink Tubing - Installation Always select the heat shrink tube in such a manner that the diameter following full recovery (post-heating) is only slightly less than the object that it is intended to cover - this will allow for maximum heat shrink wall thickness and therefore optimum electrical insulation and protection. When applying a heat shrink tube, cut the tube to the length required (if not already precut), making sure that the cut has a straight edge. A poor or jagged cut may result in the heat shrink tubing to split during application. Slide the heat shrink over the application to be covered i.e. cables (low or high voltage), pipes, conduits, electrical equipment, wire harness etc. Metal objects with a large mass should be heated prior to application to avoid uneven shrinkage of the product, or areas of poor shrinkage (called “cold spotting”). Shrink the heat shrink onto the object to be covered, starting at one end using a heating appliance for this procedure, for example a heat gun. The optimal heat shrinking temperature is detailed in the product specification and is vital to assure a short shrinking period and even shrinkage of the product. Thinner wall heat shrink products will shrink faster than those with a heavier wall, and the object to be covered will be heat affected less during the process. Ensure even heat distribution in order to prevent overheating. Overheating of the heat shrink tube will cause bubbles, discolouration or even splitting of the tubing. Heat shrink with adhesive lining may have a discharge at the open end of the tubing - this is normal and creates an environmental water-proof heat shrink seal. After application, always allow the heat shrink to cool before bending or installing the final unit.