Understanding FEP as a Tubing Material

Fluorinated ethylene propylene, or FEP, is a fluoropolymer with a variety of beneficial material properties that make it particularly useful for tubing applications.

Whereas shrink tape products are designed to wrap around a composite part before the curing process (and even remain wrapped around that part depending on the application), FEP layflat tubing is designed to shrink around different types of tooling — such as mandrels, inflatable bladders, and SMART tooling — to serve as a release layer, meaning it’s intended to enable the quick and easy part removal post-cure.

The term “layflat tubing” refers to how the size of the tubing is determined. Essentially, the width of the outside diameter of the tubing when it is laying flat on a surface can be doubled to identify the maximum circumference or perimeter of the tubing when applied around parts.

Helpful resources and additional information on tubing:

Performance Advantages of Dunstone FEP Layflat Tubing

Shrink sleeves such as FEP layflat tubing are more essential than ever as part manufacturers seek to maximize production capacity in today’s high-demand, high-volume environments. Here, we’ll explore several reasons why Hi-Shrink FEP tubing from Dunstone is the ideal choice when compared to other release layer solutions.

  • Thinnest Material Available — The greatest advantage of our Hi-Shrink FEP layflat tubing is that it’s the thinnest shrink tubing currently available. The immediate advantage here is that thinner material equates to less material, thereby creating cost savings and improving profitability on part production. Our FEP shrink tubing can be produced as thin as .04445 mm — vastly thinner than competitors’ standard of .10 mm.
  • Improved Bladder Performance — Closely related to the above is the fact that thinner FEP tubing results in reduced inflatable bladder distortion. This is due to lower shrink force and lower shrink percentage (around 10%, give or take 2% — diameter only; the tubing will not shrink in length). Despite this, our FEP tubing shrinks up to 66% faster than competing tubing, saving even more time in labor and tooling preparation.
  • Faster Sleeving — Using other release layer solutions such as shrink tape or non-shrink film could require time-consuming hand application followed by an equally extensive removal process. Additionally, non-shrink films won’t conform to mandrel and bladder surfaces as well since they do not shrink with heat. With FEP layflat tubing, sleeving is a much faster process, and the shrink process can be initiated quickly with just a heat gun.
  • Prevents FOD — Foreign object debris is a common problem when workers are hand-taping tooling and can lead to poor part performance, damage, and other unwanted effects. With FEP layflat tubing, tooling is sleeved with a consistent material without the risk of contaminants finding their way onto the tool or composite part surface.
  • Reduces Mark-Off — Ensuring a clean, consistent surface finish is critical, but with taped-on release liners or other adhesive products, the results can be anything but. Because FEP shrink tubing only has a small seam down its length, the impact on the surface finish is drastically reduced or eliminated altogether. Simply sleeve the part with the seam on a corner or angle, and it will be drastically less visible.
  • Extensive Size Options — Every application is unique. To support your success, Dunstone can provide our Hi-Shrink FEP tubing in a variety of layflat sizes (anywhere from 64mm up to 500mm) as well as custom spool lengths (up to 1,000 feet of continuous length). This ensures that you’re able to order a sufficient amount of material in the dimensions you need for a lower cost than other solutions and remain productive.
  • Custom Solutions — In addition to standard FEP shrink tubing, Dunstone is fully capable of developing custom solutions as needed. Our shrink tubing is also now available as custom-made, non-shrink preforms. We are always open to customizing our proven products to take their performance even further. Simply let us know what your application entails, and we’ll develop a solution to maximize your success.

Experience the Benefits of FEP Layflat Tubing Firsthand

Dunstone is proud to offer complimentary samples of our Hi-Shrink FEP tubing in standard, available sizes to help you determine effectiveness for your application. Simply reach out to us, and we’ll send you a sample length of FEP tubing that we currently have in stock. We’re confident that you’ll experience the benefits that we’ve outlined here.

Should you have any questions, you can connect with us anytime.