Edge Protection for Steel Coils and Metal Sheets

Published 26 October 2026 · By Ranjeet Kumar, Proprietor, Solution Enterprises

Short answer: steel coils and sheet packs are damaged mostly at their edges — by lifting gear, by strap tension and by knocks during loading. Edge protection is a stiff layer placed over those edges so that the force is spread out instead of biting into the metal or tearing the wrap. On a coil it sits on the inner and outer diameter edges; on a sheet pack it runs along the corners under every strap.

Steel looks tough, so its packaging is often treated as an afterthought. The trouble is that the buyer pays for flat, clean, undamaged metal. A dent on the edge of a coil can travel several wraps deep, and those wraps may have to be cut away before the line can use the rest.

Where the damage actually happens

The German insurers’ Transport Information Service (TIS) lists the usual causes for steel sheet in coils. Wire ropes or chains used as slings can distort the edges. Coils lifted or set down too hard become distorted, which causes problems when the coil is unwound. Edges get dented or torn, and coatings such as zinc get scraped. If strapping breaks, the coil can loosen and telescope, letting dirt in to mark the surface.

Older patent literature on coil protectors makes the same point from the mill’s side: hooks, clamps and binder bands scratch the soft inner wraps and the edges next to the eye, and that metal becomes scrap further down the chain. Sheet packs have a simpler version of the problem. Each strap pulls hardest at the four corners of the pack, and a forklift tine or a neighbouring load hits the long edges first.

Point	Typical cause	What protects it
Coil eye	C-hooks, mandrels, slings	Inner edge protector, wrap tucked into the eye
Outer edges	Slings, knocks, lashings	Outer edge protector or ring
Circumference	Strap pressure, contact with other cargo	Outer cover and seal protectors under straps
Sheet pack corners	Strap tension, tines	Angle board along each corner

How a sea-freight coil package is built

TIS describes an example package for pickled-and-oiled or cold-rolled coils going by sea. The order of the layers is the useful part, because it shows what each piece is there for:

1. Paperboard edge protectors on the inner and outer diameter edges, so the paper and film laid over them are not creased or torn.
2. Paper — fibre-reinforced or plastic-coated kraft, or corrosion-inhibiting (VCI) paper for unoiled cold-rolled coil.
3. Plastic film, with paper and film running well into the coil eye on both sides.
4. An outer cover of scrap sheet over the circumference, faces and eye, with sheet-metal edge protectors that have drainage holes.
5. Steel straps, both through the eye and round the circumference, with seal protectors under the circumferential straps, and tags that include a “keep dry” symbol.

Two details are easy to miss. For galvanised coil, TIS advises against corrosion-protection paper because it can react with the zinc. And for electrical steel and tinplate, coils usually travel “eye to the sky” on a base, with the outer cover overlapping the base so that water cannot run in.

Where paper edge protectors fit

Paper angle board does its best work in three places on metal loads:

• Sheet packs and slit-strip bundles. An L-profile on each vertical and horizontal corner takes the strap load and keeps the strap from cutting the top sheets. A U-profile or wrap-around shape suits a single exposed edge, such as the long side of a stack of plates.
• Under lashings. TIS advises edge protection wherever lashings could damage the coils. A short length of angle board under a chain or strap does exactly that.
• Inside the wrap. As the first layer in the TIS sequence, paperboard edge pieces stop film and paper from splitting at the sharp coil edges.

For heavy plate and strap loads, thickness matters more than leg size, because the board has to stay flat under high strap tension. Our note on angle board GSM and ply explains what changes when you go thicker. For round coil edges, a straight angle board is not the right shape; circular inner and outer protectors are made for that job, and we do not make those.

Plastic protectors are the other common choice. Their makers point out that polyethylene does not absorb moisture, which matters on outdoor or long sea routes. Paper board is stiffer for its cost on straight edges, goes into the same recycling stream as the paper wrap, and is easy to cut to the exact length of a sheet pack. A practical split is plastic or metal rings on the coil itself, and paper angle board on sheet packs and under lashings.

Moisture is the other half of the job

Mechanical damage is visible. Corrosion often is not, until the buyer unwraps the coil. TIS states that corrosion on steel begins at around 40% relative humidity and speeds up above 60%. Temperature swings can also cause condensation inside the packaging even when no outside water gets in, which is why TIS recommends a label telling the receiver not to unwrap the steel until it reaches room temperature.

For paper edge protectors this means two things. Keep them dry before use, because a damp board placed against steel brings water into the package. And when metal loads move through the Indian monsoon or across the tropics, plan the wrap as a moisture barrier first; our guide to edge protectors in monsoon humidity covers storage of the boards themselves. For sector-wide notes on metal parts, see automotive packaging.

A short checklist before despatch

• Every strap crosses a protector at every edge it touches — no bare metal under a strap.
• Seal joints sit on a protector or seal guard, not on the coil surface.
• Protectors are long enough to cover the full edge under the strap, with a margin either side.
• Boards and wrap were stored dry, and the coil was not wrapped while cold in humid air.
• Handling marks are visible from the side the crane or forklift will approach.

Common questions

Can paper edge protectors be used on bare steel?

Yes, and the TIS example places paperboard protectors directly on the coil edges. The board must be dry. If the steel is sensitive to corrosion, the paper and film layers that follow do the moisture work.

Which profile suits a sheet pack?

An L-profile on each corner where straps cross is the usual choice. Use a U-profile when a single edge needs covering on both faces.

Do coils need protection under lashings in a container?

TIS recommends edge protection wherever lashings could damage the coil. A short protector under each lashing point is a low-cost way to follow that.

We make paper angle board in L, U, V and wrap-around shapes; the U-shape edge protector page lists the dimensions we can make. Send your pack sizes and strap layout through request a quote.

Sources

• GDV Transport Information Service (TIS), Steel sheet in coils — packaging layers, handling damage, corrosion thresholds, securing.
• US Patent 4,516,892, Protector for the core and adjacent edges and face portions of a coil of material.
• US Patent 6,783,833, Protector for sheet metal coils.
• Signode, OD/ID Protector (Plastic) — product description of polyethylene coil edge protectors.

General guidance, not a packing instruction for any specific steel grade. Follow your mill’s and your buyer’s packing specification, and check securing arrangements with your freight forwarder.