news — from the mill.
Production notes, industry updates, and a little colour on what we’re making this month.
PPGI Supplier Due Diligence for Middle East Importers
To reduce risk when buying PPGI coil from a Chinese manufacturer, Middle East importers should treat due diligence as a documentation and verification process, not a price negotiation. In practice this means: define the exact specification and standard edition in the contract, request a complete mill test certificate and coating data before production, agree on […]
Read →DX51D vs S250GD: Choosing Galvanized Substrate for Painting
For a prepainted (PPGI) coil, the galvanized substrate grade should match the most demanding forming step the strip will survive after painting, not the finished part’s name. As a general industry rule: choose DX51D or DX52D when the painted strip must be roll formed, bent, or profiled with tight radii; choose S250GD or S350GD when […]
Read →GI Substrate for PPGI: Zinc Coating Quality Explained
How does galvanized substrate quality affect final prepainted coil performance? In short: the GI substrate determines how well paint adheres, how evenly the coil forms, and how the cut edge behaves — a poor zinc surface can ruin an otherwise good paint system. The zinc coating on a hot-dip galvanized (GI) coil is not just […]
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PPGL Galvalume Paint Compatibility and Coating Adhesion
Paint peels off galvalume coil when the pretreatment and primer system designed for a zinc surface is used unchanged on an aluminium-zinc surface. PPGL needs different pretreatment chemistry, different primer chemistry and tighter process control than PPGI because the substrate it must bond to is not the same material. Galvalume® is a hot-dip metallic coating […]
Read →PPGI vs PPGL Roof: Which Coil Should You Buy?
For most roofing projects, the honest answer is: choose PPGI (prepainted galvanized) when the roof is inland, cut edges are protected or sealed, and budget discipline matters more than maximum cut-edge corrosion resistance. Choose PPGL (prepainted galvalume) when the roof sits in coastal, industrial, high-humidity or heavily polluted air, when sheets are long and heavily […]
Read →PPGI Coil Weight, ID and Shipping Preferences
Order a PPGI coil whose actual weight, inner diameter (ID) and eye orientation match three constraints at once: what your decoiler or uncoiler can hold and pay off, what your crane or forklift can lift safely, and how the coil will be loaded into and unloaded from the container or truck. If you tell a […]
Read →PPGI Storage and Handling: Preventing Site Damage
To avoid white rust and coating damage before installation, store PPGI coil and sheets indoors or under a ventilated, condensation-free cover, keep them off the ground on dry battens, stack them so air can move around every coil or bundle, and lift them with fabric slings or a spreader beam rather than chains or forklift […]
Read →PPGI Edge Corrosion: Cut-Edge Protection That Works
Cut edges of prepainted roofing rust first because the paint film — the barrier that protects the flat surface — is severed by shearing, slitting or drilling, exposing bare steel and the metallic coating at the most electrochemically active point on the sheet. The exposed zinc (or zinc-aluminium) coating then has to protect the steel […]
Read →PPGI Sandwich Panel Facing Foam Delamination
To stop foam from separating from a PPGI facing in an insulated panel, you must control four interfaces at once: the coil surface, the primer/adhesive layer, the foam chemistry, and the line conditions during foaming and curing. Delamination is rarely caused by one factor alone. In most troubleshooting investigations, it is the result of a […]
Read →PPGI Roofing Profile Design: Rain, Wind and Uplift
To choose PPGI thickness and profile for a given roof span and wind load without over-specifying, start from the load path rather than from a catalogue: the wind uplift pressure on the roof surface is transferred through the sheet’s rib geometry into the fasteners and then into the purlins. The controlling variables are the tributary […]
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