Manufactured to ISO 9001 and CE execution class standards. Fully compatible with our cold-formed C/Z purlin secondary framing networks for rapid installation and optimum weight-to-strength ratios.
Completed Heavy Industrial PEB & Steel Framing Projects
Years of Precision Engineering & Export Excellence (Since 2010)
Structural Engineers, Metallurgists & Field Specialists
Multinational EPC Contractors & Satisfied Developers
Cold-formed galvanized C purlins (Cee profiles) represent the critical load-transferring secondary framing member in modern pre-engineered steel buildings (PEB), high-bay logistics warehouses, and solar structural canopies. Certified according to EN 1090-1 and EN 1090-2 (Execution Classes EXC2 & EXC3), our C purlins are roll-formed from structural steel grades conforming to EN 10346 (such as S280GD, S350GD, and ultra-high tensile S450GD/S550GD).
The mechanical efficiency of a C-section lies in its asymmetric mono-symmetric cross-section, engineered with a precision-drawn lip return (typically 15mm to 25mm) that imparts superior lateral-torsional buckling resistance. Under transverse gravity loads (dead load, snow load, mechanical services) and uplift suction forces induced by cyclonic wind phenomena, the purlin’s second moment of area ($I_x$) and section modulus ($W_x$) govern the maximum span capability without exceeding serviceability deflection limits (typically constrained to span/200 for metal roofs and span/300 for brittle plasterboard ceiling assemblies).
Factory Production Control (FPC) Guarantee: Every batch leaves our facility backed by an EN 10204 Type 3.1 Inspection Certificate verifying heat chemistry, minimum yield strength ($R_{eH}$ ≥ 350 MPa), ultimate tensile strength ($R_m$), elongation at fracture ($A_{80}$ ≥ 16%), and zinc coating thickness measured via electromagnetic induction.
Calculated in accordance with EN 1993-1-3 (Eurocode 3: Design of cold-formed thin-gauge members). Available in custom lengths up to 14.5 meters with CNC continuous pre-punched web and flange holes.
| Profile Designation | Web Depth (D mm) | Flange (B mm) | Lip (C mm) | Nominal Gauge (mm) | Weight (kg/m) | Moment of Inertia Ix (cm⁴) | Section Modulus Wx (cm³) | Yield Strength (MPa) |
|---|---|---|---|---|---|---|---|---|
| C100/15 | 100 | 50 | 15 | 1.50 - 2.00 | 2.45 - 3.22 | 38.2 - 49.1 | 7.64 - 9.82 | S350GD (≥ 350) |
| C140/18 | 140 | 60 | 18 | 1.60 - 2.50 | 3.58 - 5.48 | 104.5 - 156.2 | 14.93 - 22.31 | S350GD / S450GD |
| C160/20 | 160 | 65 | 20 | 1.80 - 2.80 | 4.46 - 6.82 | 162.8 - 244.1 | 20.35 - 30.51 | S350GD / S450GD |
| C200/20 | 200 | 70 | 20 | 1.80 - 3.00 | 5.25 - 8.62 | 295.4 - 472.1 | 29.54 - 47.21 | S350GD / S450GD |
| C250/22 | 250 | 75 | 22 | 2.00 - 3.20 | 6.78 - 10.70 | 578.2 - 898.4 | 46.25 - 71.87 | S350GD / S450GD |
| C300/25 | 300 | 85 | 25 | 2.20 - 3.50 | 8.64 - 13.56 | 1092.0 - 1690.5 | 72.80 - 112.70 | High-Bay Logistics |
| C350/30 (Heavy) | 350 | 100 | 30 | 2.50 - 4.00 | 11.85 - 18.72 | 1980.5 - 3080.0 | 113.17 - 176.00 | Clear Span ≥ 12m |
Cold-formed sections offer up to 35% steel weight savings compared to traditional hot-rolled IPE and channel sections, significantly trimming primary frame foundation footprints and freight tariffs.
Multi-axis hydraulic punching accommodates round (14mm, 18mm) and slotted (14x22mm, 18x26mm) holes for standard M12/M16 cleat connection bolts, sag rods, and lateral anti-torsion bridging assemblies.
Manufactured strictly to EN 10162 tolerance criteria: web height camber within ±1.0mm, flange squareness within ±1.5°, and overall straightness deviation under L/1000, eliminating on-site reaming.
Atmospheric durability is governed by zinc barrier density and galvanic sacrificial defense mechanisms. When secondary framing is subjected to industrial condensation, chemical off-gassing, coastal salinity, or high-humidity tropical microclimates, untreated carbon steel deteriorates rapidly. We provide hot-dip galvanized finishes spanning Z120 (120 g/m²) up to heavy marine-grade Z600 (600 g/m² combined both sides) in full compliance with EN ISO 1461 and ASTM A653.
For aggressive C4 and C5-M corrosive zones (fertilizer processing facilities, coastal livestock buildings, or marine logistics hubs), we manufacture C purlins using cutting-edge Zinc-Aluminum-Magnesium (ZM/ZAM/PosMAC) ternary alloy coatings. The addition of 1.5%–3.0% magnesium and aluminum activates a tenacious, insoluble Simonkolleite ($Zn_5(OH)_8Cl_2 \cdot H_2O$) protective boundary layer. This specialized patina self-heals cut edges, punched holes, and fastener scratches, delivering up to four times the atmospheric service lifespan of conventional pure zinc coatings at equivalent thickness.
Procurement managers, structural specifiers, and EPC general contractors must navigate macroeconomic supply shifts, stringent building regulations, and digital transformation.
Traditional 2D shop drawings are rapidly being supplanted by direct digital workflows. Structural engineering models developed in Tekla, Revit, or Vertex BD export IFC and NC1 files directly to computerized roll formers, eliminating transcription discrepancies and guaranteeing millimeter accuracy for slotted hole patterns.
With the European Union Carbon Border Adjustment Mechanism (CBAM) fully implemented, supply chain transparency regarding embodied carbon (Scope 1, 2, and 3 emissions) has become paramount. Our purlin coils utilize Electric Arc Furnace (EAF) and optimized BOF steel feedstocks with full Environmental Product Declarations (EPD).
Commercial and industrial roofs are universally designed as power-generating assets. Modern procurement demands C-sections with higher web-depth-to-thickness ratios capable of handling supplemental dead loads of 15 to 25 kg/m² for solar racking without requiring expensive secondary retrofitting.
The industry is shifting from mild S250/S280 grades toward S450GD and S550GD cold-rolled alloys. Using thermo-mechanically controlled rolling processes (TMCP), these high-strength steels permit substantial gauge reductions while maintaining section stiffness, significantly reducing maritime container freight costs.
Joint Star Steel Structure Ltd. (operating since 2010 under the motto “Your Future in Your Home”) has evolved into an authoritative leader in pre-engineered steel buildings, heavy structural fabrication, and secondary envelope systems. Backed by 352+ successfully handed-over projects across multiple continents, our engineering department unites 100+ dedicated structural engineers, detailers, certified welding inspectors (CWI), and erection superintendents.
Unlike simple purlin roll-formers who operate as component traders, we manage the complete design-fabrication-erection lifecycle. We manufacture our own EPS, PU, and Rockwool sandwich panels, process prepainted steel coils, build heavy built-up portal columns, and supply all cold-formed structural members. This unified approach eliminates coordination gaps between primary steel frames and secondary purlins, ensuring zero on-site fitting conflicts.
Detailed technical answers to common queries submitted by procurement officers, civil engineers, structural consultants, and warehouse developers.