Original Raychem patent for heat-shrinkable tubing

Original Raychem patent for heat-shrinkable tubing. 

Thin-walled (approximately 0.010-0.040 in., or 0.25-1.0 mm) tubing is usually selected by continuous service temperature, which may range from 90°C (194°F) for some PVC tubing up to 250°C (482°F) for tubing made from PTFE. The main use of thin shrink tubing is in electrical and electronic applications. 

METHOD AND APPARATUS FOR EXPANDING PLASTIC TUBING Filed May 29,1963 2 Sheets-Sheet 1 

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