Heat shrinkable fluoropolymer sleeves can be manufactured from a variety of materials including FEP, PFA, and PTFE all of which have very similar low surface energy but different mechanical properties. The selection of the right fluoropolymer material to construct the heat shrinkable sleeve depends on the application type.
FEP
The most common material found in the market is FEP due to its relatively low cost and ease of fabrication and installation. Due to it being a transparent material, when adhesive bonding is required it is easy for the installation technician to visually inspect that all air pockets have been removed and a good adhesive bond is achieved. FEP sleeves are commonly offered in 0.020” (0.5mm) or 0.060” (1.5mm) thickness and for rollers up to 18” in diameter, heat shrinkable sleeves can be expanded from an extruded tube, meaning that the resultant roll cover is seamless. FEP sleeves are ideal for low wear positions such as conveyor rollers and guide rollers.
PFA
Similar to FEP, PFA is also a transparent material and can be offered as a seamless cover. While the material is more expensive to manufacture than FEP, a PFA sleeve has the advantage of having higher thermal stability and greater flex fatigue life than FEP. With the combination of a seamless sleeve, ease of installation, and higher flex and temperature resistance, PFA is the ideal choice to cover rubber nip rollers that run high compression force.
PTFE
Unlike FEP and PFA, PTFE heat shrinkable roll covers are opaque and cannot be extruded. This means that covers are always provided with a seam where the sheet is welded together. However, PTFE has the highest flex resistance of all fluoropolymers in addition to having 10 times the abrasion resistance of FEP as shown in Figure 6.
With a higher working temperature rating and improved flex fatigue resistance, a PTFE heat shrinkable cover can operate significantly longer and under a wider range of environments than FEP and PFA heat shrinkable sleeves. This makes PTFE the best choice for equipment in the harshest environments such as felt rolls that require the longest possible sleeve wear life.
Fluoron couples the extraordinary material characteristics of fluoropolymers with patented capabilities in plastic welding and manufacturing, coating, and bonding of large diameter heat shrinkable tubing. With over 50 years of experience providing custom fluoropolymer solutions, Fluoron guarantees we will enable you to iterate to a solution faster than any other fluoropolymer supplier. With our commitment to the fastest response and delivery times, and best in class customer service, Fluoron’s hands-on technicians will install our product and walk through any problems that arise. We are not satisfied until our customers are.