Halogen-Free Flame-Retardant TPU Cable Compound | HFFR Jackets & Strain Reliefs
Halogen-Free Flame-Retardant (HFFR) TPU Cable Jacket
TPU cable jacket systems engineered for halogen-free flame strategy projects, where compliance goals must be achieved
without sacrificing practical extrusion stability and jacket reliability.
This page focuses on the most common failure modes seen in HFFR jackets and how grade positioning and processing choices reduce trial risk.
Many HFFR projects fail not because “FR is missing”, but because flame strategy is pursued without balancing
toughness, surface integrity, and process stability—especially on thick-wall jackets and high-output extrusion lines.
toughness, surface integrity, and process stability—especially on thick-wall jackets and high-output extrusion lines.
Halogen-Free FR Strategy
Process Stability
Toughness Balance
Thick-Wall Jackets
Extrusion Jacket
Shore 80A–98A
Process Stability
Toughness Balance
Thick-Wall Jackets
Extrusion Jacket
Shore 80A–98A
Typical Applications
- Indoor building and infrastructure cables – projects prioritizing halogen-free FR strategies while maintaining jacket durability.
- Public facilities and transportation cable runs – applications where flame performance and material behavior under heat exposure are critical.
- Industrial control and equipment cables – designs requiring FR strategy plus stable extrusion, surface quality and handling toughness.
Quick Grade Selection (Shortlist)
Choose “Balanced” when
- General HFFR requirement with practical durability
- Handling toughness matters during installation
- You prefer a wider, more stable extrusion window
Choose “High-Safety” when
- Higher compliance margin is needed for the project
- Thicker jackets or higher-risk installations are expected
- Retesting cost is high and stability is the priority
Note: Final grade selection depends on cable construction, jacket thickness, processing window, and target standards (e.g., UL94 / VW-1 or other regional requirements).
Common Failure Modes (Cause → Fix)
In HFFR jacket projects, most issues come from an imbalance between flame strategy, mechanics, and processing. Use the table below as a quick diagnostic:
| Failure Mode | Most Common Cause | Recommended Fix |
|---|---|---|
| Brittleness / cracking after installation | Flame package too aggressive; toughness margin reduced | Move to a balanced HFFR grade family; verify bending/handling on finished cable |
| Orange peel / micro-cracks on thick-wall jackets | Narrow processing window; moisture; overheating | Dry thoroughly; lower melt temperature; reduce shear; stabilize line speed and cooling |
| Unstable extrusion behavior | Excessive shear; inconsistent drying; temperature drift | Optimize screw/setup; tighten temperature control; standardize drying and feeding |
| Over-specifying a single flame metric | Chasing FR targets without durability validation | Validate flame + mechanical durability together at target wall thickness and cable construction |
A reliable HFFR jacket system is designed to meet flame strategy targets while preserving
mechanical robustness and manufacturing repeatability.
mechanical robustness and manufacturing repeatability.
Typical Grades & Positioning
| Grade Family | Hardness | Design Focus | Typical Use |
|---|---|---|---|
| TPU-CBL HFFR Balanced | 80A–95A | Halogen-free FR strategy with balanced toughness and stable extrusion behavior | General HFFR cable jackets where handling durability matters |
| TPU-CBL HFFR High-Safety | 90A–98A | Higher flame strategy margin while maintaining practical jacket integrity | More demanding compliance targets, thicker jackets, higher-risk installations |
Note: Final grade selection depends on cable construction, jacket thickness, process window, and target standards (e.g., UL94 / VW-1 or other regional requirements).
Key Design Advantages
- Halogen-free flame strategy with engineering balance—not “FR at any cost”.
- Practical toughness retention to reduce cracking and installation damage risk.
- Process stability designed for continuous extrusion and repeatable surface quality.
- Positioned grade families that shorten selection time for different compliance and thickness scenarios.
Processing & Recommendations (3-Step)
1) Dry
Dry compounds thoroughly before extrusion. Moisture can destabilize melt flow and degrade surface integrity.
2) Control Heat & Shear
Keep a controlled melt temperature profile and avoid excessive shear. Overheating and aggressive screw setups narrow the process window.
3) Validate on Real Cables
Thick-wall jackets amplify instability. Verify flame strategy and mechanical durability on finished cables at target wall thickness and test conditions.
- Thickness awareness: Confirm settings on your target wall thickness, not only on thin samples.
- Temperature stability: Avoid drift during long runs; keep melt and die zones consistent.
- Verification: Validate flame + durability together under your relevant standards.
Is this page for you?
You will benefit most if:
- You need an HFFR jacket but cracking happens after installation
- Your thick-wall jacket shows orange peel, micro-cracks, or weak surface integrity
- Your extrusion window is narrow and jacket appearance is inconsistent
- You want a clear grade shortlist to reduce trial and retesting risk
Request Samples / TDS
If you are building a halogen-free flame strategy cable jacket and want to reduce trial risk,
contact us for a recommended grade shortlist and technical data sheets based on your cable structure,
jacket thickness, target standards and extrusion conditions.
To get a fast recommendation, send:
- Cable type and construction (indoor/building, industrial control, etc.)
- Jacket wall thickness and target hardness
- Target standards (UL94 / VW-1 / UL1581 or regional requirements)
- Extrusion line conditions (output rate, screw type if known)
