# Back-to-Back Strut Channel 41x42mm URL: https://www.chinneelectric.com/products-types/strut-channel/back-to-back-strut-channel-41x42mm/ Brand: Chinne Electric ## Summary Chinne Electric Strut Channel 41x21mm. Available in hot-dip galvanized, fire-retardant powder coated, and standard powder coated finishes. Perforated design for heavy or medium-duty use.. Product Brief. ## Key facts - Standards: IEC 61537 - Corrosion protection & aesthetics - Fire-resistant, insulated & circuit-safe - Heavy-duty corrosion protection, weather resistance ## FAQ ### What are the standard dimensions and material thickness of the 41x42mm back-to-back strut channel? The back-to-back strut channel is formed by spot-welding two 41×21 mm slotted steel channels into a rigid 41×42 mm box-section profile. The standard material thickness is 2.0 mm, while a 2.5 mm option is available for heavy-duty configurations. Standard length is 3 000 mm, with custom lengths available upon request. Elongated slots measure 14 mm × 28 mm and are spaced at 50 mm intervals. These dimensions conform to IEC 61537, and dimensional tolerances are verified by type testing at accredited third-party laboratories. ### How does the 41x42mm back-to-back strut channel compare to a single 41x21mm channel in terms of structural performance? The 41×42 mm back-to-back configuration delivers significantly higher bending stiffness and torsional rigidity compared to a single 41×21 mm channel. By welding two half-size channels into a closed box-section, the profile resists twisting and deflection more effectively under medium-load conditions. This makes it suitable for MEP support, cable tray hangers, and pipe routing where structural integrity is critical, yet the overall depth remains only 42 mm—more compact than the 41×82 mm twin 41×41 system—allowing installation in space-limited runs without sacrificing load-bearing capacity. ### What international standards does the 41x42mm slotted strut channel comply with? The 41×42 mm back-to-back strut channel conforms to several international standards governing design, material, and safety. These include IEC 61537 for cable tray and cable ladder systems, BS 6946 for metal channel support systems, ASTM A653 for steel sheet zinc-coated by the hot-dip process, ASTM A123 for hot-dip galvanized coatings, UL 2239 for hardware for the support of conduit and cable, and NEMA VE 1 for metal cable tray systems. Compliance is substantiated through type testing at accredited third-party laboratories, ensuring reliable performance in building wiring and industrial installations. ### What corrosion-resistant finishes are available for the 41x42mm back-to-back strut channel? Multiple corrosion-resistant finishes are offered to suit different environmental conditions. Options include pre-galvanized (zinc-coated steel sheet conforming to ASTM A653), hot-dip galvanized after fabrication (meeting ASTM A123 requirements for thicker zinc coverage), stainless steel for superior corrosion resistance in harsh or wash-down environments, and aluminum for lightweight applications requiring natural oxidation resistance. The selection of finish should be based on the installation environment’s corrosivity category, with hot-dip galvanized or stainless steel recommended for outdoor and high-humidity locations to maintain structural integrity over time. ### Is the 41x42mm back-to-back strut channel compatible with standard Unistrut fittings and channel nuts? Yes, the 41×42 mm back-to-back strut channel is designed as a Unistrut-compatible system and works with standard 41 mm channel nuts, brackets, and MEP accessories. The 14 mm × 28 mm elongated slots accept conventional spring nuts and toothed channel nuts, enabling fast, adjustable connections without field drilling. This compatibility allows engineers and installers to integrate the channel into existing modular framing and support assemblies using widely available fittings, reducing procurement complexity. Chinne Electric confirms that all slot geometry and dimensional tolerances align with the interface requirements specified in IEC 61537 for interoperable channel support systems. ## Content Technical Specifications The Chinne Electric 41×21 mm strut channel conforms to the dimensional and performance requirements of IEC 61537. Dimensional tolerances, material grades, and mechanical load data are verified by type testing at accredited third-party laboratories. Profile dimensions: 41 mm (height) × 21 mm (width) Material thickness: 2.0 mm (standard); 2.5 mm available for heavy-duty configurations Standard length: 3 000 mm (custom lengths on request) Slot dimensions: 14 mm × 28 mm elongated slots at 50 mm longitudinal pitch Base material: DD11 mild steel per EN 10111, or DX51D+Z for continuously hot-dip coated substrate Finish options: Hot-dip galvanized to EN ISO 1461 (minimum coating 55 µm, Fe/Zn13 per IEC 61537 Table A.1) Fire-retardant polyester powder coating, 80–120 µm, self-extinguishing per IEC 60695-11-10 Class V-0 Standard polyester powder coating, 60–100 µm, RAL 9005 (black) or RAL 7035 (light grey) Perforation type: continuous slotted, push-through design compatible with M8–M12 spring channel nuts Yield strength (base steel): 235 MPa minimum (typical 250–280 MPa) Mass per metre: 1.85 kg/m (2.0 mm thickness); 2.30 kg/m (2.5 mm thickness) Beam load capacity (simply supported, L=1 m): 4.2 kN uniformly distributed load at deflection L/200 (2.0 mm profile) Packaging: 10 pieces per bundle, strapped with edge protectors and moisture-barrier wrap Applications This 41×21 mm profile is specified for medium-duty cable management and mechanical support structures where dimensional consistency and predictable load behaviour are required. Typical installations include: Building wiring support systems in commercial and residential risers, corridors, and plant rooms Industrial equipment frameworks, machine-level cable trays, and instrumentation mounting rails Commercial electrical infrastructure, including distribution board back frames and busbar support bracketry HVAC control panel substructures and sensor mounting rails in technical building services Perforated variants simplify bolted connections without field drilling, maintaining the integrity of the corrosion protection system Compliance and Standards IEC 61537: Cable tray systems and cable ladder systems — the product is designed, tested, and marked in accordance with this standard. Mechanical load classification and coating durability are declared per Annex A and Annex B of IEC 61537. EN ISO 1461: Hot-dip galvanized coatings on fabricated steel articles — applicable to the HDG finish variant; minimum local coating thickness of 55 µm on steel 2.0–6.0 mm thick. IEC 60695-11-10: Fire hazard testing — the fire-retardant powder coat formulation meets V-0 criteria for vertical flame spread and afterflame time on the channel surface. RoHS (EU 2011/65/EU, amended): All powder coat finishes are free of restricted substances above threshold limits. Declarations are available on request. Frequently Asked Questions What is the load classification of the 41×21 mm strut channel under IEC 61537? Under IEC 61537, the product achieves a mechanical load classification that corresponds to a safe working load of 4.2 kN per metre span at a deflection limit of L/200, when simply supported with uniform loading. The declared classification is stamped on the channel web at 1 000 mm intervals per marking requirements of IEC 61537 Clause 7. For specific span and support conditions, refer to the manufacturer's load tables or request project-specific calculations. How does the fire-retardant powder coating differ from standard powder coating in operational terms? The fire-retardant variant uses an intumescent-modified polyester formulation tested to IEC 60695-11-10 and achieves V-0 classification — meaning the coating self-extinguishes within 10 seconds after removal of the flame source and does not produce flaming drips. Standard powder coating (non-fire-retardant) is tested for adhesion and UV stability but carries no flame-spread classification. The fire-retardant option is specified for enclosed building escape routes, tunnels, and installations where surface flame propagation must be limited. Coating adhesion and corrosion resistance values are equivalent between the two variants; the difference is exclusively in reaction-to-fire performance. Can the 41×21 mm channel be used in outdoor or coastal environments? Yes, when specified with the hot-dip galvanized finish to EN ISO 1461. With a minimum average coating thickness of 55 µm (Fe/Zn13), this variant is suitable for C3 (medium) and C4 (high) corrosivity categories per ISO 12944-2, covering most urban, industrial, and coastal atmospheres. For C5-M (severe marine) environments, supplementary duplex coating or stainless steel alternatives should be evaluated. The standard powder-coated variant is rated for C1–C2 interior conditions only and must not be used outdoors. All field-cut ends must be treated with zinc-rich repair compound (minimum 93% zinc in dry film) to maintain the corrosion protection system's continuity.