PTFE/FEP Dual Wall Heat Shrink Tubing

Material Introduction

Dual-Shrink Tubing is a high-performance dual wall heat shrink structure featuring an outer layer of PTFE and an inner layer of meltable FEP. When heated, the inner FEP melts to create a seamless, hermetic seal, while the PTFE outer layer shrinks tightly to provide exceptional mechanical stability. This double wall heat shrink design delivers superior chemical resistance, outstanding high-temperature endurance (up to 200°C), and excellent electrical insulation. As a premium type of double wall heat shrink tubing, it is engineered for critical environments that require long-term durability and reliable protection.

Product Features

1. Superior Sealing & Environmental Protection

The dual-wall PTFE/FEP construction functions as a high-reliability dual wall tubing, forming a hermetic barrier once heated. The PTFE outer layer shrinks into a tough, protective jacket, while the inner meltable FEP flows to encapsulate components and prevent moisture, gases, and contaminants from entering. This makes it ideal for sealing connectors, splices, and terminals in demanding sectors such as aerospace, automotive, new energy, and chemical processing—where double wall heat shrink performance is essential.

2. Exceptional Chemical & High-Temperature Resistance

The PTFE outer layer inherits excellent chemical resistance to nearly all substances, including strong acids, alkalis, solvents, and oils. This dual wall heat shrink tubing maintains operational stability at temperatures up to 260°C, ensuring long-term protection of components exposed to corrosive chemicals, elevated heat, or extreme industrial environments.

3. Reliable Electrical Insulation & Mechanical Durability

The PTFE exterior provides outstanding electrical insulation with high dielectric strength and a low dielectric constant that remains stable across a wide frequency range. As a robust dual wall shrink tubing, it also enhances mechanical durability by protecting wires and components from abrasion, vibration, and cut-through. This dual protection ensures electrical integrity and long service life in critical wiring systems and high-performance electronics.

4. Permanent, Contour-Conforming Fit

Once heated, the dual-wall PTFE/FEP tubing forms a permanent, low-profile installation that conforms tightly to irregular shapes without rebounding. The seamless seal provides excellent strain relief and prevents fluid ingress, ensuring long-lasting reliability. As a versatile form of double wall heat shrink tubing, it features a 1.7:1 / 2:1 shrink ratio, excellent sealing performance, and strong chemical resistance. It also meets VW-1 flame-retardant standards and complies with RoHS, REACH, and FDA requirements, making it suitable for medical, industrial, and aerospace use.

Application Fields

This advanced double wall heat shrink tubing is engineered for demanding applications requiring superior sealing, insulation, and chemical resistance. It is widely used across industries including:

Aerospace & aviation

Rail transportation

New energy vehicles

Sensors & precision instruments

Military and defense systems

Electrical and electronic devices

Power distribution systems

Medical and food-processing equipment

Its ability to perform reliably under harsh conditions makes it a preferred protective solution for sensitive and mission-critical components.

FAQ

1. How does it work?

This dual wall heat shrink tubing features a PTFE outer layer and a meltable FEP inner layer. When heat is applied, the outer jacket shrinks while the inner layer melts and flows to form a seamless, hermetic, and protective seal around the component.

2. How is it installed?

Slide the tubing over the component to be protected. Apply heat evenly using a hot-air gun or industrial oven. The PTFE outer wall will shrink, and the FEP inner layer will melt to create a tight, uniform, bubble-free seal without damaging the underlying material.

3. Is it suitable for high-temperature applications?

Yes. The PTFE outer construction allows continuous operation up to 200°C and remains dimensionally stable under extreme thermal conditions, making this dual wall tubing ideal for high-heat environments.

4. What advantages does it offer over standard tubing?

Compared with ordinary heat shrink tubing, this double wall heat shrink product offers:

Chemical-inert PTFE exterior

High-temperature resistance

A meltable inner layer that forms a waterproof, permanent seal

Superior electrical insulation

Enhanced mechanical strength and abrasion resistance

These properties make it especially suitable for aerospace, medical, industrial, and other high-reliability fields requiring the benefits of dual wall shrink tubing technology.