Procurement for engineering projects is never straightforward, even when dealing with seemingly simple parts like heat shrink tubing. PTFE is a common material for heat shrink tubing, but it's available in a wide range of sizes and with many varied characteristics. Choosing the correct tubing for your application has significant implications on the durability and reliability of your final product.
When selecting the right tubing, you'll need to consider many factors, some of which are likely to be highly specific to your particular application. While no one article can cover every possible consideration, these four factors provide a good starting point for making an informed decision.
1. Object Shape
Before making any other decisions, you'll need to consider the shape of the object you're wrapping in PTFE tubing. Highly irregular objects have a significant variation in their coverage requirements. In other words, part of your object may be much larger than other parts. Shrink ratio is the primary characteristic to consider when dealing with object shape.
In general, a higher shrink ratio works better for irregular objects. With a high shrink ratio, you'll have enough space to fit the tubing over the entire part, but it will ultimately shrink enough to form a tight bond over any irregularities. Tubing with a lower shrink ratio works better for consistently sized objects since the expanded tubing diameter will not need to accommodate bulges or protrusions.
2. Heat Resistance
Not all PTFE tubing offers similar heat resistance. High temperatures can degrade PTFE, potentially reducing its ability to insulate against heat and electricity. Most PTFE has an operating range of up to roughly 500° Fahrenheit, but specifications can vary slightly between manufacturers. If you're working with a high-temperature application, it's essential to consider the safe operating range of your tubing.
3. Moisture Resistance
PTFE is naturally resistant to moisture, but it requires a tight bond with your underlying part to provide a genuine moisture seal. Not all PTFE tubing works in this way, so be sure you're sourcing an appropriate variety if water exposure or significant levels of humidity are a concern. The shrink ratio is critical here since the tubing must firmly bond to the underlying surface to seal adequately.
4. Flexibility
Finally, ensure that you are purchasing tubing with the flexibility to suit your needs. Less flexible tubing may offer greater strength in some cases, but it will be unsuitable for oddly shaped parts, wiring, or other situations with complex twists and turns. If your application has any of these characteristics, be sure to consider flexible or semi-rigid tubing instead of rigid PTFE.
For more information about PTFE heat shrink tubing, contact a local business near you.
