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multi-core industrial cable

3 Min Read
C PUR Design Integration: FLEXIFESTOON PUR characteristics (inherited): Outer sheath: PUR (polyurethane, compact) Insulation: Special TPE (superior elongation) Central unit: Textile (mechanical support) Weight: 25–30% lighter than standard rubber Diameter: 15–20% smaller than rubber equivalent Cost: +15–25% premium over rubber Service life: 10–15 years (extended) Screened design addition (new): Screen: Tinned copper braid (EMC shielding) Coverage: 80–90% (good EMC performance) Diameter impact: +2–3 mm (screen adds ~3 mm to diameter) Weight impact: +500 kg/km (braid + outer sheath) Cost: Additional +10–15% for screen layer Combined C PUR result: vs. Unscreened PUR (FLEXIFESTOON PUR): FLEXIFESTOON PUR: Minimal diameter/weight, no EMC C PUR: Slightly larger (screen added), excellent EMC Choice: PUR for maximum compactness (non-EMI environments) C PUR for VFD motors, confined spaces with EMC requirements vs. Standard rubber screened (GRDGCGÖU-J): GRDGCGÖU-J: Standard diameter, heavy, rubber durability C PUR: Compact diameter, lightweight, superior oil/chemical resistance Choice: GRDGCGÖU-J for simple temporary festoon C PUR for permanent industrial machine tool installation Nomenclature: FLEXIFESTOON® = Product family (flexible cable) C = Screen (copper braid, "C" from German "Schirm") PUR = Material (polyurethane jacket) Result: "FLEXIFESTOON C PUR" = Screened compact polyurethane cable
Technical Department
on15/05/2026

FLEXIFESTOON® C PUR

C PUR Design Integration: FLEXIFESTOON PUR characteristics (inherited): Outer sheath: PUR (polyurethane, compact) Insulation: Special TPE (superior elongation) Central unit: Textile (mechanical support) Weight: 25–30% lighter than standard rubber Diameter: 15–20% smaller than rubber equivalent Cost: +15–25% premium over rubber Service life: 10–15 years (extended) Screened design addition (new): Screen: Tinned copper braid (EMC shielding) Coverage: 80–90% (good EMC performance) Diameter impact: +2–3 mm (screen adds ~3 mm to diameter) Weight impact: +500 kg/km (braid + outer sheath) Cost: Additional +10–15% for screen layer Combined C PUR result: vs. Unscreened PUR (FLEXIFESTOON PUR): FLEXIFESTOON PUR: Minimal diameter/weight, no EMC C PUR: Slightly larger (screen added), excellent EMC Choice: PUR for maximum compactness (non-EMI environments) C PUR for VFD motors, confined spaces with EMC requirements vs. Standard rubber screened (GRDGCGÖU-J): GRDGCGÖU-J: Standard diameter, heavy, rubber durability C PUR: Compact diameter, lightweight, superior oil/chemical resistance Choice: GRDGCGÖU-J for simple temporary festoon C PUR for permanent industrial machine tool installation Nomenclature: FLEXIFESTOON® = Product family (flexible cable) C = Screen (copper braid, “C” from German “Schirm”) PUR = Material (polyurethane jacket) Result: “FLEXIFESTOON C PUR” = Screened compact polyurethane cable
3 Min Read
PUR vs. Rubber Sheath Comparison: EPR/PCP rubber (traditional festoon): Base polymer: Ethylene-propylene or chloroprene rubber Density: ~1.2 g/cm³ (light) Young's modulus: ~2–8 MPa (soft, flexible) Tear strength: 15–30 kN/m (adequate) Tensile strength: 8–12 MPa (moderate) Oil resistance: Fair (EPR), Good (CPE) Cost: Low (commodity material) Typical life: 5–10 years PUR (polyurethane, FLEXIFESTOON PUR): Base polymer: Polyol + isocyanate urethane linkage Density: ~1.25 g/cm³ (slightly heavier per unit volume, but better properties) Young's modulus: ~10–15 MPa (stiffer, stronger) Tear strength: 30–50 kN/m (2–3× better than rubber) Tensile strength: 12–18 MPa (much stronger) Oil resistance: Excellent (far superior to rubber) Cost: Medium (specialty material) Typical life: 10–15 years (50–100% longer) PUR performance advantages: (1) Tear resistance: Mechanism: Urethane linkages form strong hydrogen bonds More rigid polymer network, resists crack propagation Consequence: Cable survives snagging on sharp edges Abrasion resistance 2–3× better than rubber Application: Machine tool environments (sharp metal edges, high speed) (2) Oil immersion durability: Rubber swelling in oil: 8–15% volume increase PUR swelling in oil: 2–5% volume increase (excellent stability) Result: Cable diameter remains stable, connections don't loosen No electrical performance degradation from oil ingress (3) Ozone & UV resistance: Rubber degradation rate: 10–20% strength loss per 5 years outdoor PUR degradation rate: 5–10% strength loss per 5 years outdoor Application: Outdoor machine tools, conveying systems in sunlight (4) Mechanical stress recovery: Rubber behavior: After bending, slow recovery (viscoelastic) PUR behavior: Rapid recovery, lower hysteresis loss Benefit: Lower heating during high-speed cycling 240 m/min reeling applications tolerate higher duty cycles Cost-benefit trade-off: PUR premium cost: +15–25% vs. standard rubber festoon cable Justification for premium: - 2× longer service life (10–15 years vs. 5–10 years) - Reduced maintenance/replacement downtime in industrial operations - Superior performance in aggressive environments (oil, chemicals) - Better value when cost-of-downtime is high (machine tools, production lines)
Technical Department
on15/05/2026

FLEXIFESTOON® PUR

PUR vs. Rubber Sheath Comparison: EPR/PCP rubber (traditional festoon): Base polymer: Ethylene-propylene or chloroprene rubber Density: ~1.2 g/cm³ (light) Young’s modulus: ~2–8 MPa (soft, flexible) Tear strength: 15–30 kN/m (adequate) Tensile strength: 8–12 MPa (moderate) Oil resistance: Fair (EPR), Good (CPE) Cost: Low (commodity material) Typical life: 5–10 years PUR (polyurethane, FLEXIFESTOON PUR): Base polymer: Polyol + isocyanate urethane linkage Density: ~1.25 g/cm³ (slightly heavier per unit volume, but better properties) Young’s modulus: ~10–15 MPa (stiffer, stronger) Tear strength: 30–50 kN/m (2–3× better than rubber) Tensile strength: 12–18 MPa (much stronger) Oil resistance: Excellent (far superior to rubber) Cost: Medium (specialty material) Typical life: 10–15 years (50–100% longer) PUR performance advantages: (1) Tear resistance: Mechanism: Urethane linkages form strong hydrogen bonds More rigid polymer network, resists crack propagation Consequence: Cable survives snagging on sharp edges Abrasion resistance 2–3× better than rubber Application: Machine tool environments (sharp metal edges, high speed) (2) Oil immersion durability: Rubber swelling in oil: 8–15% volume increase PUR swelling in oil: 2–5% volume increase (excellent stability) Result: Cable diameter remains stable, connections don’t loosen No electrical performance degradation from oil ingress (3) Ozone & UV resistance: Rubber degradation rate: 10–20% strength loss per 5 years outdoor PUR degradation rate: 5–10% strength loss per 5 years outdoor Application: Outdoor machine tools, conveying systems in sunlight (4) Mechanical stress recovery: Rubber behavior: After bending, slow recovery (viscoelastic) PUR behavior: Rapid recovery, lower hysteresis loss Benefit: Lower heating during high-speed cycling 240 m/min reeling applications tolerate higher duty cycles Cost-benefit trade-off: PUR premium cost: +15–25% vs. standard rubber festoon cable Justification for premium: – 2× longer service life (10–15 years vs. 5–10 years) – Reduced maintenance/replacement downtime in industrial operations – Superior performance in aggressive environments (oil, chemicals) – Better value when cost-of-downtime is high (machine tools, production lines)
26 Min Read
To understand bending radius in the context of electrical cables, imagine a cable being bent around a curved path. The bending radius is the radius of curvature of that path—specifically, it measures the distance from the center point of the curve to the centerline of the cable as it follows the curve. For a cable being routed around a small pulley or through a tight corner in a power chain, the bending radius is the radius of the pulley or corner curve. The reason bending radius matters profoundly is that when a cable bends, the material on the inside of the curve is compressed and the material on the outside is stretched. This creates mechanical stress throughout the cable's cross-section. The conductors on the inside of the bend are under compressive stress, while those on the outside are under tensile stress. The insulation around the conductors experiences similar stress. If the bending is too tight—if the radius of curvature is too small—the mechanical stress exceeds what the conductor strands and insulation materials can tolerate, leading to permanent deformation, cracking of the insulation, or even breaking of individual conductor strands. Over time, repeated bending at excessive stress levels leads to progressive damage accumulation and eventual cable failure. The specified minimum bending radius is the tightest curve the cable can safely navigate repeatedly without suffering mechanical damage. Understanding this distinction is essential for mechanical and electrical engineers designing cable routing systems for moving equipment.
Technical Department
on04/03/2026

Bending Radius Guide: How Tight Can You Bend ÖLFLEX FD 855 P 18G1.5 Continuous Flex Cable?

To understand bending radius in the context of electrical cables, imagine a cable being bent around a curved path. The bending radius is the radius of curvature of that path—specifically, it measures the distance from the center point of the curve to the centerline of the cable as it follows the curve. For a cable being routed around a small pulley or through a tight corner in a power chain, the bending radius is the radius of the pulley or corner curve. The reason bending radius matters profoundly is that when a cable bends, the material on the inside of the curve is compressed and the material on the outside is stretched. This creates mechanical stress throughout the cable’s cross-section. The conductors on the inside of the bend are under compressive stress, while those on the outside are under tensile stress. The insulation around the conductors experiences similar stress. If the bending is too tight—if the radius of curvature is too small—the mechanical stress exceeds what the conductor strands and insulation materials can tolerate, leading to permanent deformation, cracking of the insulation, or even breaking of individual conductor strands. Over time, repeated bending at excessive stress levels leads to progressive damage accumulation and eventual cable failure. The specified minimum bending radius is the tightest curve the cable can safely navigate repeatedly without suffering mechanical damage. Understanding this distinction is essential for mechanical and electrical engineers designing cable routing systems for moving equipment.