news — from the mill.
Production notes, industry updates, and a little colour on what we’re making this month.
Galvanized Steel Coil Tolerances and PPGI Fabrication
Galvanized coil tolerances matter more after painting, not less. If the substrate is going to be painted and roll-formed, thickness, width, camber, flatness and coil weight tolerances determine how much steel you actually buy, how much paint and zinc you carry per finished metre, how stable the line runs, and how much scrap appears at […]
Read →PPGI Coil Storage and Handling After Delivery
Most white rust and edge damage found on prepainted galvanized (PPGI) coils after arrival is caused at the buyer’s yard, not at the mill. The usual culprits are outdoor storage without ventilation, coils resting directly on wet ground, stacked loads that crush the outer wraps, lifting with chains or forks against the coil face, and […]
Read →How to Audit a PPGI Coil Supplier: A Practical Checklist
To verify that a PPGI supplier actually controls the painting line rather than reselling another mill’s coil, ask for evidence that links three things together: the substrate heat number, the coil’s painting record, and the finished coil label. If a supplier can produce a continuous, unbroken chain from raw galvanized substrate to painted coil — […]
Read →PPGI for Roofing and Wall Cladding Systems
For a standing seam roof on an industrial building, the usual starting point is a structural-grade or higher-strength substrate with a substantial zinc coating, a paint system chosen for the specific atmospheric environment, and a coating thick enough to survive roll forming and seaming without cracking. A common specification direction is something in the range […]
Read →PPGI Coil for Roll Forming and Profiling Lines
If your profiling line is cracking paint at the bends, the honest answer is that it is usually both a coil problem and a setup problem — but they are diagnosable separately. Paint micro-cracking at a bend appears when the tensile strain imposed by the tooling exceeds the elongation the coating system can tolerate at […]
Read →PPGI Coil Buyer Questions: Southeast Asia & Middle East
Buyers in Southeast Asia and the Middle East typically ask the same cluster of questions: how well will PPGI coil resist humidity, salt air and intense UV; how many coils fit in a container; which RAL colours are actually available; how long production and delivery take; and what documents must accompany the shipment. The short […]
Read →GI Substrate Quality: How It Shapes PPGI Performance
The quality of the galvanized (GI) substrate affects the final PPGI coil more than most buyers expect. Zinc coating uniformity, spangle condition, surface cleanliness, oil residue and flatness all influence how the paint adheres, how the coating cures, how the strip forms, and how the finished product resists corrosion. In practical terms, a poor GI […]
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PPGL Galvalume Substrate: What Buyers Must Know
The galvalume substrate inside PPGL coil is a hot-dip aluminium-zinc alloy coating (typically around 55% aluminium, 43.4% zinc and 1.6% silicon by mass in the common commercial composition) applied to steel, and it behaves differently from a pure zinc coating in two ways that matter to paint: its surface chemistry is aluminium-rich, and it forms […]
Read →PPGI versus PPGL for Roofing Projects
For most roofing projects, the practical answer is this: choose PPGL (prepainted galvalume) when the roof will face long-term moisture, salt, industrial fallout, or a corrosive atmosphere and you want the strongest cut-edge and overall corrosion resistance from the metallic coating; choose PPGI (prepainted galvanized) when the environment is mild to moderate, the budget is […]
Read →Gloss and Color Control in PPGI Production
Gloss and color in prepainted galvanized iron (PPGI) are controlled by three things working together: a stable paint formulation, a tightly managed coating line, and an agreed measurement method. Color is matched to a target such as an RAL number, then verified by instrument rather than by eye. Gloss is set by the paint chemistry […]
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