Before you sign for a load of HR coils, run six checks in order: confirm the coils and paperwork match the truck, verify dimensions with your own gauge at multiple points, inspect the edges and surface for defects, check the shape for coil set and edge wave, cross-read the mill test certificate against the physical tags, and photograph anything wrong before the driver leaves. The signature on the delivery note is the moment risk transfers to you. Everything below is about not signing away money you can’t get back.
Here’s the uncomfortable part. Most buyers don’t do this. The coils arrive, someone checks the gross weight against the invoice, and the rest is hope. Weight tells you that steel showed up. It tells you nothing about whether the steel is the right thickness, the right grade, or free of the surface and shape defects that turn into scrap on your shear line three weeks later.
We make HR coils at R.P. Multimetals every coil leaves our plant in Mandi Gobindgarh with its own test certificate and we’d still rather you inspected ours than took them on faith. A buyer who knows how to check quality is a buyer who keeps suppliers honest. Including us.
Why weight-only acceptance costs you
Picture the shear line a fortnight after delivery. The operator feeds a coil, and the strip won’t track straight the edges ripple, the cut pieces come out skewed, and the scrap bin fills faster than the finished stack. Now you’re on the phone to the supplier, who asks for proof the defect arrived with the coil and wasn’t created on your own line. You don’t have it. You weighed the load and signed.
That’s the whole problem with weight-only acceptance. Unprocessed strip off the coil must be inspected to evaluate the as-shipped quality before you can claim for defects that your own processing could have caused things like edge wave, dents, scratches, and surface contamination. Once the strip has run through your equipment, the line between “mill defect” and “your defect” blurs, and the supplier holds the better hand. Inspection at delivery isn’t bureaucracy. It’s the evidence that protects your claim.
So spend twenty minutes. Here’s the order.
The HR coil inspection checklist
Step 1 — Match the delivery to the order before anything comes off the truck
Start at the paperwork, not the steel. Is this even your shipment? Check the delivery note carries your name and the correct site if your firm runs multiple yards, loads do go to the wrong one. Count the coils against the dispatch document. Then read the physical tag on each coil: grade, heat number, dimensions, coil weight.
What goes wrong: the tags don’t match the mill test certificate travelling with the load. A mismatch here a heat number on the coil that isn’t on the MTC means you can’t trace that specific coil to its tested chemistry, and an untraceable coil is a coil you shouldn’t accept. Catch it now, while the truck’s still loaded and refusal is easy.
Step 2 — Look at the packaging and the outer wraps
Torn moisture-proof paper and snapped strapping aren’t cosmetic. Torn wrapping or broken steel straps usually mean one thing: rust moisture got in during transit or storage. Walk the load and note any coil that’s been crushed, telescoped (the wraps slipping sideways into a cone), or banded so loosely the turns have shifted.
Light, tight mill scale on a hot rolled surface is normal that blue-grey skin comes with the process and isn’t a defect. What you’re hunting for is the other thing: red rust, flaky loose scale, pitting, water staining on the exposed wraps.
What goes wrong: people wave through a coil because “it’s only the outer wrap.” Sometimes true. But heavy red rust on the outside is the visible end of a moisture problem that may run deeper, and on a coil you’ll later pickle or paint, corrosion is exactly what ruins the coating. Flag it, photograph it, decide before you sign.
Step 3 — Measure thickness and width yourself, at multiple points
Do not take the tag’s word for it. Pull out a micrometer or thickness gauge and measure and measure properly. Take readings at a minimum of five cross-sections per coil rather than relying on the factory figure, and check thickness at both edges and the centre at each one. HR coil thickness varies across the width when the rolling mill isn’t set right, so a single centre reading hides the problem.
Know your tolerance before you start. A deviation within about ±3% is acceptable for standard orders; precision-grade material should be held far tighter. If you bought to a defined IS or ASTM table, the allowable tolerance for your exact nominal thickness is written there bring that number to the dock, not a vague sense of “about right.” Our own HR coil ships from 1.6mm to 4mm thick and 100mm to 300mm wide, and the spec sheet states the tolerance band so a buyer can verify against it instead of guessing.
While you’re measuring: check the coil’s inner diameter. Most lines run a standard ID of around Φ508mm or Φ610mm, and an ID off by more than about ±5mm can stop the coil seating on your decoiler mandrel. A coil you can’t mount is a coil you can’t run, however perfect the steel.
What goes wrong: measuring one spot, dead centre, and calling it done. The thin edge that fails your part comes from the reading you didn’t take.
Step 4 — Inspect the edges and the surface
Edges first, because the edge shows trouble before the body does. Run your eye and your hand (carefully) along the cut edge. Edges should be straight and free of burrs, sharp slivers, or waviness; burrs are a handling hazard and cause problems when the coil is later cut or formed. Look at the top turns of the coil for the lengthwise lines that signal cracks, folds, seams, or overlaps in the rolling direction.
Then the face. Cracks, folds, and seams reduce strength and can cause failure during bending or welding, so inspect the top turns very carefully and downgrade or reject coils with deep or long cracks. Note dents, gouges, deep scratches, and any oil or foreign-particle contamination beyond the light protective film.
What goes wrong: confusing normal hot-rolled mill scale with a defect, or the reverse accepting a deep seam because the rest of the surface looked fine. A seam runs lengthwise and reopens under load. One bad seam can write off the run it’s in.
Step 5 — Check the shape: coil set, edge wave, and buckle
Shape is where good-looking steel quietly fails. Three things to know by name.
Coil set is the curve the strip keeps after it comes off the coil the steel “remembers” being wound. It happens when material that wasn’t properly tension-levelled, or that’s uneven in thickness, tries to spring back toward its coiled shape. A little is normal and levels out. A lot fights your line.
Edge wave is the ripple along the edges. Aim for edge waviness of roughly 0.5mm per metre or tighter; wavy edges stop the strip feeding straight, which wastes material and can damage equipment.
Centre buckle is the same idea in the middle of the strip rather than the edge bumps and fullness you’ll see when the coil’s laid flat.
The field test is simple: lay a sample length on a flat surface and look down it. Waviness, fullness, a strip that won’t sit flat all of it shows up against a true surface and a straight edge. This is the check that separates HR coil that processes cleanly from coil that doesn’t, and it’s the one weight-only buyers never make.
What goes wrong: assuming flat-looking steel is flat. It isn’t, until you’ve checked it against something that actually is.
Step 6 — Verify the mill test certificate against the physical coil
The MTC is the document that says what the steel is chemistry and mechanical properties, heat by heat. Yield strength, ultimate tensile strength, and percentage elongation come from a tensile test on a sample cut from the coil, and those results are posted on the test certificate before the coil ships. Your job at delivery is to confirm the certificate in your hand belongs to the coil in front of you, and that its numbers meet your order.
Read it like this:
- Heat and coil numbers on the MTC must match the physical tags. Verify that the labels batch number, grade, specs line up exactly with the mill test certificate. This is the traceability spine; without the match, nothing else on the page is anchored to your steel.
- Chemistry — carbon, manganese, sulphur, phosphorus, and any specified alloying falls inside your grade’s limits.
- Mechanical properties — yield, tensile, elongation meet the grade you bought.
- Standard referenced is the one you ordered to.
- IS 10748 compliance (where applicable) — For HR coils supplied for cold rolling, strip rolling, or related processing applications, confirm that the coil is manufactured and tested in accordance with IS 10748. Verify that the MTC references the correct standard and that all specified mechanical properties, chemical composition limits, and dimensional tolerances meet the requirements of IS 10748.
What goes wrong: treating the MTC as a formality and filing it unread. Don’t rely solely on the supplier’s certificate uncoil a sample and check the material itself, because the paper and the steel don’t always agree. The certificate and your own measurements are two witnesses; you want both saying the same thing.
This is also where an integrated supplier earns its place. When the same company melts the scrap, casts the billet, and rolls the coil, the MTC traces back through one controlled chain rather than three handoffs the heat number on the tag leads to a melt that mill actually ran. A re-roller buying billets on the open market can’t always offer that depth of traceability. (We’ve written separately on scrap-based versus primary steel and why chain control, not the feedstock label, is what governs quality.)
Step 7 — Document everything, then sign
If you’ve found problems, this step is the one that pays. Take photos of the material as it’s offloaded; detailed, dated documentation lays the trail an insurer or carrier follows during a claim. Note defects on the delivery receipt itself coil number, defect, location before signing. Keep your measurement records.
One piece of counter-intuitive freight wisdom worth borrowing: unless the entire load is wrong, don’t turn the driver away note the damage, sign with the exceptions recorded, and accept the shipment, because refusing outright can cost more and weaken your position. The exception is wholesale: wrong grade across the load, wrong product entirely, gross shortfall. Then refuse and call the supplier. For isolated damage, document on the note, accept, and claim you stay in control of the material and the evidence.
How many coils should you inspect per delivery?
Inspect every coil for tags, packaging, and visible surface and edge condition that pass is quick and catches the obvious. For dimensional and shape checks, measure a representative sample across the load, and increase the sample the moment you find a defect.
A practical mill rule: if the same defect shows up in two coils from the same production series, stop and inspect the rest of that series rather than processing on. Two coils with the same fault isn’t bad luck. It’s a pattern pointing at the run they came from.
What’s the difference between a mill test certificate and a delivery note?
The delivery note (or proof of delivery) records what physically arrived coil count, weights, condition and your signature on it transfers risk to you. The mill test certificate records what the steel is: its heat number, chemical composition, and mechanical test results, traceable to the specific coil. The delivery note protects the logistics; the MTC protects the metallurgy. You check the coils against both, and you don’t sign the delivery note until the MTC and the physical tags agree.
The habit worth building
Weight at the gate, then hope, is how most HR coil gets accepted in this country. It’s also why so many quality disputes end with the buyer eating the loss no measurements, no photos, no recorded exceptions, no leg to stand on. The fix costs twenty minutes and a thickness gauge.
Build the routine: paperwork, packaging, dimensions, surface, shape, certificate, documentation. Run it the same way every load. Suppliers notice which buyers inspect, and they send their better coils to the yards that check which is the quiet reason we’d encourage you to check ours. If you want to see what a coil that’s built to pass this checklist looks like, the HR coil specifications are published with tolerances stated, or you can talk through grades and process windows with the team before you order.