Hose & Wire-Harness Covers TPU Compound | Flexible, Kink-Resistant, Fuel/Oil Resistant
Hose & Wire-Harness Covers TPU Compound
TPU compounds designed for automotive hose protection and wire-harness protective covers used in vehicle interior and under-hood areas.
These parts are exposed to abrasion and rubbing, assembly handling, and (project-dependent) contact with oil, fuel, and coolant.
This page focuses strictly on automotive protective covering applications, with selection guidance around abrasion protection, fluid resistance, flexibility for assembly, heat aging, and extrusion/over-jacketing processing fit.
For automotive covers, “failure” often starts as wear-through from vibration and rubbing, then becomes fluid ingress, noise, or leak risk due to compromised protection.
The correct TPU compound must balance wear resistance, assembly friendliness, and aging stability under temperature cycles.
The correct TPU compound must balance wear resistance, assembly friendliness, and aging stability under temperature cycles.
Abrasion / Scratch Protection
Oil / Fuel / Coolant Resistance
Assembly-Friendly Flexibility
Heat Aging Stability
Weathering (Project-Dependent)
Extrusion / Over-Jacketing Fit
Oil / Fuel / Coolant Resistance
Assembly-Friendly Flexibility
Heat Aging Stability
Weathering (Project-Dependent)
Extrusion / Over-Jacketing Fit
Typical Automotive Applications
- Under-hood hose covers: abrasion and scuff protection in high-vibration zones (project-dependent)
- Wire-harness sleeves / over-jackets: protection from rubbing against brackets, metal edges, and adjacent assemblies
- Routing protection parts: covers on harness/hose routing points where contact wear is likely
- Interior harness protection: flexible covers for assembly-friendly routing with stable appearance and long-term integrity
Quick Grade Selection (Shortlist)
Choose “Wear Protection” when
- Abrasion and scuff resistance is the main risk
- Rubbing occurs under vibration against brackets or adjacent parts
- You need stable surface durability with practical extrusion window
Choose “Fluid & Heat” when
- Oil / fuel / coolant resistance is critical (project-dependent)
- Heat aging stability under temperature cycles is a key requirement
- Long service life is required and retest cost is high
Note: Final selection depends on cover thickness, contact conditions, under-hood temperature window, fluid exposure media, and the processing route (extrusion or over-jacketing).
Key Performance Focus
Abrasion & Scratch Protection
Designed to resist wear-through from vibration rubbing. Consider both surface abrasion and cut/edge contact conditions at routing points.
Oil, Fuel, Coolant Resistance
Resistance packages can be tuned for specific media (project-dependent). Validate swelling and property retention after fluid exposure aging.
Flexibility & Assembly Friendliness
Covers must stay flexible for routing and installation without kinking or cracking, especially at bends and clamp points.
Heat Aging & Weathering
Under-hood parts experience heat cycles that can change stiffness and wear rate. Outdoor zones may require weathering resistance (project-dependent).
Noise / Rub Behavior
Surface friction and contact behavior influence squeak/rub risk. If noise is a concern, share your contact pairing and test method (project-dependent).
Process Consistency
Extrusion stability and dimensional control matter for assembly fit. Stable melt behavior reduces thickness variation and surface defects.
Common Failure Modes (Cause → Fix)
Most issues appear as wear, hardening, swelling, or assembly-related damage. Use the diagnostic table below:
| Failure Mode | Most Common Cause | Recommended Fix |
|---|---|---|
| Wear-through / scuff damage at routing points | Insufficient abrasion resistance; edge contact or vibration rubbing is severe | Move to wear-protection positioning; validate abrasion and cut resistance at target thickness and contact type |
| Softening / swelling after oil/fuel/coolant exposure | Media incompatibility (project-dependent); long-term exposure reduces property retention | Select media-resistant positioning; validate volume change and mechanical retention after fluid aging |
| Hardening or cracking after heat aging | Heat cycle aging reduces flexibility; material balance not stable under temperature window | Upgrade heat aging package; validate stiffness drift and elongation retention after heat aging |
| Assembly damage / tearing during installation | Flexibility insufficient; thickness and hardness not matched to routing radius or clamp stress | Adjust hardness and toughness balance; confirm installation radius and clamp load; consider tougher package for edges |
| Surface squeak / rub noise | Surface friction pairing causes noise under micro-movement (project-dependent) | Optimize surface behavior package; confirm with your pairing and NVH test method |
| Dimensional instability / thickness variation in extrusion | Process window not stable; moisture or temperature control issues | Dry thoroughly; stabilize melt temperature and line speed; optimize die and cooling for consistent wall thickness |
If your project requires abrasion + fluid resistance + heat aging + noise control at the same time, the most effective route is a stacked package with validation on real parts.
Use the Advanced Functional page to start a multi-constraint shortlist.
Use the Advanced Functional page to start a multi-constraint shortlist.
Typical Grades & Positioning
| Grade Family | Hardness | Design Focus | Typical Use |
|---|---|---|---|
| TPU-AUTO COV Wear Protection | 90A–60D | Abrasion / scratch resistance with assembly-friendly flexibility and stable extrusion behavior | Harness sleeves and hose covers where vibration rubbing and scuff risk dominate |
| TPU-AUTO COV Fluid & Heat | 90A–65D | Fluid resistance (oil/fuel/coolant, project-dependent) + heat aging stability under under-hood cycles | Under-hood covers and high-risk areas requiring long-term property retention |
Note: Exact positioning should be confirmed based on exposure media, temperature window, cover thickness, and your extrusion/over-jacketing process settings.
Processing Fit: Extrusion & Over-Jacketing
1) Dry
Dry TPU thoroughly before extrusion. Moisture can cause bubbles, surface defects, and unstable output leading to thickness variation.
2) Stabilize Melt & Line Speed
Stable melt temperature and controlled shear help maintain consistent viscosity and surface quality. Match die design and cooling to target wall thickness.
3) Control Cooling & Shrink
Cooling uniformity affects shrink and dimensional fit. For tight assembly tolerance, share your target OD/ID and thickness window for matching.
- Over-jacketing bonding (project-dependent): Share substrate and surface condition if bonding/adhesion is required.
- Assembly friendliness: Provide minimum bend radius, clamp style, and installation method to avoid tearing or kinking.
- Validation suggestion: Run combined tests for abrasion + heat aging + fluid exposure if service life requirements are strict.
Request Samples / TDS
Contact us for a shortlist and technical data sheets based on your cover design, service conditions, and processing route. For under-hood projects, sharing the temperature window and exposure media greatly improves first-trial success rate.
To get a fast recommendation, send:
- Part type (hose cover / harness cover), target thickness, and key dimensions (OD/ID)
- Contact condition: rubbing severity, edge contact risk, installation and clamp style
- Exposure media (oil/fuel/coolant, project-dependent) and exposure pattern
- Under-hood temperature window and aging requirement
- Process route (extrusion or over-jacketing) and basic line conditions
- Noise concern (if any) and your NVH test method (project-dependent)
