Advanced Polymers' clear polyester heat shrink tubing can be used effectively in
fusing tubes together. Typically, tubes of dissimilar properties - one stiff and
one flexible - are joined. An easy way to accomplish this is to insert a mandrel
in the tube ends to keep them from collapsing, butt the two ends together, and shrink
a piece of tubing over them. Since polyester tubing has a low shrink temperature,
the parts do not distort during this initial process.
In tube joining, clear polyester heat shrink tubing is used
to hold a low durometer clear tube and high durometer white tube tightly together
for fusing (top). The heat shrink tube is shown partially removed (middle)and completely
removed from the joint (bottom). Thumb tack is for size reference.
The shrinking process squeezes the tubes and holds them together tightly during
fusing. Because of polyester's high melt temperature, the high heat applied to fuse
the tube ends does not melt the shrink tubing. After the tubes are joined, the shrink
tubing can be left on or peeled off to leave an ultra smooth surface finish. Nicking
the shrink tubing at one end before shrinking facilitates removal. Since the polyester
tubing is clear, the operator can see when the tubes are fused. The ability to "see"
the process is very useful in product development and production to avoid applying
too much or too little heat.