Application and Selection of XLPO Compound

Cables that crack, melt, or emit smoke in service lead to costly downtime and safety risks. Cross-linked polyolefin (XLPO) compounds eliminate these problems by resisting heat, oil, and mechanical stress—without halogens.

XLPO compounds are used as insulation and jacketing materials across multiple cable applications. They offer consistent thermal stability, electrical insulation, mechanical strength, and environmental resistance.

This article outlines where XLPO compounds are used, and offers a clear selection checklist to help engineers and buyers choose the right grade for their project.

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Typical Applications of XLPO in Cable and Industrial Systems

Tired of PVC jackets stiffening in cold or sagging in heat? XLPO offers a cleaner-burning, longer-lasting, and halogen-free alternative.

Key Industries Using XLPO

1. Automotive Wire Harnesses

Used in engine bays and EV battery packs, XLPO grades resist 125 °C continuous temperature, splash oil, and flexing. They comply with ISO 6722, LV 112, and SAE J1128.

2. Solar Cables (PV Wires)

Cables exposed to sun, ozone, and humidity demand high UV stability and flexibility at –40 to 120 °C. XLPO compounds meet TÜV 2 PfG 1169, IEC 62930, and 25-year weather life.

3. Railway and Rolling Stock Cables

XLPO compounds with low smoke zero halogen (LSZH) formulations meet EN 45545 HL2/HL3, NFPA 130, and resist oils, de-icing salt, and impact from debris.

4. Home Appliance Wiring

Power cords near motors and heating elements use XLPO to meet UL 758 AWM ratings of 105–125 °C. These cords remain soft over time without plasticizers.

5. Heat-Shrink Tubing and Corrugated Sleeves

EB-crosslinked XLPO enables tubing that shrinks cleanly and resists split lines. Typical use includes wire routing in vehicles, robotics, and battery packs.

6. Specialty Industrial Uses

In harsh industrial settings, XLPO layers are used in hoses, battery linings, transformer insulation, and power tools.

Application Area	Role of XLPO	Key Standards	Required Properties
Automotive Wiring	Insulation & jacket	ISO 6722, LV 112	125 °C, oil, abrasion
Solar Cable	Jacket & insulation	TÜV 2 PfG 1169	UV, –40 °C to 120 °C
Railway Cable	LSZH formulation	EN 45545, NFPA 130	Smoke/toxicity, impact
Appliance Leads	Flexible insulation	UL 758 AWM	Heat, thin-wall, no plasticizer
Heat-Shrink Tubing	EB-XLPE	UL 224	VW-1 flame, shrink ratio
Industrial Hoses	Liner material	ASTM D543	Chemical & tear resistance

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How to Select the Right XLPO Compound for Your Cable Application

Choosing the wrong compound leads to scrap, test failure, or regulatory issues. Use this seven-factor checklist to choose accurately.

1. Thermal Classification

Start with continuous and short-peak temperature needs:

• 90 °C / 105 °C / 125 °C / 150 °C continuous classes
• 200–250 °C fault survival (for power cables)
• Test per IEC 60216 for aging resistance

Peroxide-cured XLPO handles higher peaks; silane XLPO balances cost and performance.

2. Voltage Class and Electrical Stress

• LV (<1 kV): Focus on mechanical/jacket integrity
• MV (1–35 kV): Requires >20 kV/mm dielectric strength
• HV (>35 kV): Demands high gel %, low dissipation

Tailor gel content and purity depending on insulation or screen layer.

3. Fire Performance Requirements

• Common standards: IEC 60332, UL VW-1, EN 45545, IEC 61034
• Use aluminum or magnesium hydroxide for halogen-free flame retardancy
• Meet IEC 60754 for acid gas and smoke toxicity if LSZH is required

Flame rating affects filler set, loading, and processing conditions.

4. Chemical and UV Resistance

Test against:

• Oils, solvents, acids (ASTM D543)
• UV (ISO 4892, Xenon arc aging)
• Ozone, salt spray, and coolants in automotive or industrial use

Add stabilizers and antioxidants to boost long-term durability.

5. Mechanical Stress and Flexibility

Applications with vibration, bending, or cable drag need:

• Lower modulus
• Abrasion modifiers
• Cold flexibility down to –40 °C (cold bend tests)

Modifying the cross-link density and elastomer content changes flex index.

6. Cross-Linking Method

Choose based on your production setup:

Method	Advantages	Limitations
Silane	Low capital cost, uses standard extruder	Slow cure, moisture control needed
Peroxide	High gel %, best for HV insulation	Needs long cure tube, steam
EB Radiation	Clean, instant, no by-products	Expensive, needs shielding

EB is great for heat-shrink; peroxide works for HV power; silane is cost-efficient for general cable use.

7. Cost and Supply Chain Fit

Compare cost per meter, not just cost per kg. Consider:

• Density (high filler = heavier cables)
• Process scrap rate
• Availability from suppliers in compliant grades

XLPO with higher filler content for flame retardancy may raise weight and price—balance that with performance gain.

Selection Factor	Relevance	Typical Range	Adjustable Through
Operating Temp	Reliability	90–150 °C	Resin type, cross-linking
Peak Temp	Fault survival	200–250 °C	Cure system
Flame Class	Regulatory compliance	VW-1, V-0, HL2	Filler choice
Electrical Stress	Insulation integrity	10–35 kV	Gel %, dielectric additives
Chemical/UV Exposure	Outdoor & industrial use	Varies	Stabilizers
Mechanical Stress	Flex/bend/crush	Moderate–High	Modifiers
Production Line Fit	Equipment & throughput	Silane / Peroxide / EB	Cure method
Cost/Meter	Project margin	$0.05–$0.50/m	Filler loading, supplier

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Summary: Choosing the Right XLPO Cable Compound

Pick XLPO when your project needs:

• Continuous high-temperature resistance
• Zero halogen, low smoke flame behavior
• Electrical insulation stability
• Chemical, UV, or abrasion resistance
• Lifecycle cost advantage over PVC or PE

Match your application's technical and regulatory needs to:

• Temperature range
• Flame and smoke standards
• Mechanical and electrical properties
• Processing method and budget

📌 Need help choosing a suitable XLPO compound?

We offer peroxide-, silane-, and EB-crosslinked XLPO grades for insulation, jacketing, tubing, and custom cable applications.

👉 Contact PESTOCHEM for datasheets and technical guidance.