Heat shrinkable polymer hose and tubing clamp

A self-adjusting hose and tubing clamp for providing a clamping force about connection ends of elastomeric hose and tubing and stems associated with automotive coolant systems comprising an oriented polymer in the form of a ring sized and shaped to be radially disposed about said connection end of said elastomeric hose and tubing to create a clamping force by heat shrinkage, said clamping force urging said elastomeric hose and tubing toward tight and sealing engagement with said stem, and acting to resist axial movement of said elastomeric hose and tubing relative to said stem, said shrinkage first occurring at an appreciable rate at a preset diameter reducing release temperature, said ring having a first nominal inside diameter defined as the diameter said ring assumes upon being shrunk in free space and being smaller than the outside diameter of said hose connection end, a second nominal inside diameter defined as the diameter said ring assumes upon being shrunk about said connection end, and a third nominal inside diameter defined as the diameter of said ring after polymer orientation and before shrinkage, said third inside diameter being greater than the outside diameter of said connection end, said first outside diameter being no greater than about 80 percent of said third inside diameter wherein said oriented polymer tends to continue to shrink upon each occurrence of said polymer reaching said release temperature, said polymer having a coefficient of expansion greater than 0.2 millimeters per meter per degree Celsius, so as to cause said clamp to self-adjust about said connection end.