FAQ – Frequently Asked Questions

FAQ – Frequently Asked Questions

Frequent questions regarding choice and use of the heatshrinkable tubes

SELECTION OF THE INTERNAL DIAMETER FOR HEATSHRINKABLE TUBING

Question: How I can calculate the optimal internal diameter for heatshrinkable sleeve?
Reply: There are different possibilities in order to find the optimal diameter for covering an object:
1) In general the internal diameter is chosen in the way that, after vacuum shrinkage, it will be 20% inferior compared to the object to be coated.
2) Having available the diameter of the object to be covered, it’s possible to find width of the flat heatshrinkable sleeve using the formula 1,57079 x diameter.
 3) Having available width of the flat heatshrinkable tube, it’s possible to find the diameter of the object to be covered using the formula 0,6366 x sleeve’s width.

UNITS OF MEASURE CONVERTION TABLE

Question: How I can convert the internal diameter dimension of a heatshrinkable sleeve from Inch to mm.?
Reply: In this case you can use the here below table:

LONGITUDINAL VARIATION RELATED TO HEATSHRINKABLE SLEEVES

Question: How can I calculate the shortening of the heatshrinkable tubing during the shrinkage stage?
Reply: Heatshrinkable tubing over narrowing diametrically, during the shrinkage stage, also they tend to shrink in the longitudinal direction. This perspective have to be considered when using tubing in cut lengths. The value relative to the longitudinal shrinkage is expressed as a percentage of the length of the cut and it is usually reported on technical data sheet.

CUTTING HEATSHRINKABLE TUBING

Question: Which measures must be implemented for the correct cut of the heatshrinkable tubing?
Reply: When cutting a shrinking tubing, you must ensure that the ends are cut with extreme precision Quando si taglia una guaina termorestringente, bisogna assicurarsi che le estremità vengano tagliate con estrema precisione. The inexact and irregular may cause breakage of the heatshrinkable tubing during shrinkage stage.

HEATING METHODS FOR THE SHRINKAGE OF HEATSHRINKABLE TUBING

Question: Quali sono i metodi più efficaci da utilizzare per l’ operazione di restringimento di una guaina termorestringente?
Reply: Heatshrinkable tubing have to be shrinked beginning just from one extremity, the most critical, and then slowly move towards the opposite extremity. This procedure allow to avoid creation of air bubble between the inner wall and the object that coated by the tubing. To obtain an optimal result we suggest to use appropriate devices for this specific operation as for example hot gun or hot air tunnel

In the case the object that have to be covered was metal or a good heat conductor, the ideal solution wold be pre-heating the object to avoid cold zone, so to permit a perfect and soft adjustment of the heatshrinkable tubing.

In order to avoid overheating of the heatshrink tubing, ensure a regular heat distribution. The excessive heating of the material during the shrinking process may cause bubbles, discolouration and some cases even the breaking of the heatshrink tubing.

STORAGE AND CONSERVATION OF THE HEATSHRINKABLE TUBING

Question: Heatshrink tubing can be stored outside of the warehouse?
Reply: For proper storage of heat shrink tubing, make sure that They are stored in a cool, dry, clean and far away from direct heat sources. The proper storage temperature is 0 ÷ + 40 ° C max with relative humidity> 75%.

OPERATING PRECAUTION USING HEATSHRINKABLE TUBING

Question: During the heating phases of the heatshrink tubing which precautions should be followed?
Reply: During the heating phases of the heatshrink tubing, is very important to ensure that working place is well aired.

Contact our technical department tecnico@rtecomponenti.it