Wire insulation in high-heat environments must resist thermal breakdown, maintain dielectric integrity, and support long-term durability. Materials like PTFE, ETFE, FEP, silicone, and XLPE are top performers. Galaxy Wire & Cable helps engineers match insulation types to demanding aerospace, industrial, and medical specs.
Why does wire insulation matter in high-temperature conditions?
Wire insulation isn’t just for electrical isolation—it’s a critical barrier that ensures reliability under thermal stress. In high-heat applications such as aerospace engines, industrial automation, or medical sterilization equipment, the wrong insulation can lead to: 
- Brittle cracking or melting
- Short circuits and signal loss
- Premature cable failure
- Regulatory compliance issues
The right insulation extends service life, ensures safety, and protects performance even in extreme operating ranges.
What are the top insulation materials for high-heat wire?
Here are the top high-temp insulation materials Galaxy Wire & Cable recommends:
| Material | Max Temp | Strengths |
| PTFE (Teflon®) | 260°C | Chemically inert, excellent dielectric, aerospace-grade |
| ETFE | 150°C | Tough, abrasion-resistant, good radiation resistance |
| FEP | 200°C | Flexible, low friction, cleanroom and medical use |
| Silicone | 200°C | Ultra-flexible, great for dynamic or coiled cables |
| XLPE | 125°C | Good thermal and electrical balance, cost-effective |
| Polyimide | 250°C+ | Exceptional thermal endurance, used in space and avionics |
Galaxy supplies these materials in both standard and custom constructions, with low minimum orders available.
How to choose insulation based on your application?
Here’s a quick decision guide:
- Aerospace or Defense: PTFE or Polyimide for extreme temp and mission-critical reliability.
- Medical Devices: FEP or Silicone for flexibility and sterilization compatibility.
- Industrial Automation: XLPE or ETFE for oil resistance and mechanical toughness.
- RF/Coaxial Systems: PTFE for consistent dielectric properties over wide frequencies.
Galaxy’s team will help balance performance, flexibility, cost, and compliance during your spec review.
What other factors should engineers consider?
- Voltage Rating: Ensure the insulation withstands peak system voltages.
- Flexibility Requirements: Dynamic cables (robot arms, coil cords) need flexible insulation like Silicone.
- Environmental Exposure: ETFE or PUR is better in oil-heavy or chemical-laden settings.
- Certifications Needed: Galaxy supports UL, CSA, MIL-SPEC, and RoHS/REACH compliant builds.
FAQ: High-Heat Wire Insulation
Q1: What’s the difference between PTFE and FEP insulation?
PTFE handles higher temperatures and has better dielectric strength, but FEP is more flexible and often easier to process.
Q2: Can Galaxy custom-design cable with multiple insulation layers?
Yes—dual or triple-layer insulation can be used for EMI shielding, chemical resistance, or physical reinforcement.
Q3: Are there halogen-free high-temp insulation options?
Yes—materials like XLPE and certain ETFE variants are available in LSZH (Low Smoke Zero Halogen) formats.
Q4: Does Galaxy provide spec sheets or test data for insulated wire?
Absolutely. Spec sheets, thermal test data, and compliance certificates are available on request.
Q5: How does insulation choice affect cable flexibility?
Materials like silicone and FEP are more flexible than ETFE or XLPE, but Galaxy can adjust conductor stranding to maintain bend radius in any configuration.