Edge protectors and corner boards with strapping: what to specify and where they go

A corner board looks like the least technical item on a packing station: a strip of folded board placed under the strap before tensioning. Yet it can decide whether cartons arrive with crushed corners, whether a strap survives a sharp edge, and whether a stack stays square on a long journey. Edge protection was not new in November 2018: Signode’s paperboard range comes from a producer that dates its laminated paperboard work to 1964, and strapping suppliers offered plastic protectors alongside board. The useful question for buyers was therefore less whether to use protectors than how to specify and place them.

This article covers corner boards for pallet strapping and the plastic protectors used on bundles and crates. It does not set strap counts or tensions; those depend on the load and belong to the packing specification.

What an edge protector is meant to do

Manufacturers describe several jobs at once. Signode’s description of laminated paperboard edge protection presents it as protection against stacking, shifting and impact damage, as a guard that holds strapping in place so it does not slip or cut into the load, and as a way to help distribute strap pressure evenly. It also notes added stability for stacked cartons under strapped or stretch-wrapped pallets. Cordstrap puts it simply: protect both the cargo and the strap.

Those are different goals, and one protector may not meet all of them. Decide which matters most for each load:

• Protecting the goods: stopping the strap from crushing carton corners or marking a finished surface.
• Protecting the strap: keeping it off a sharp or abrasive edge that could cut or wear it.
• Holding the strap in position: stopping it sliding off a corner or along a bundle.
• Stabilising the stack: helping cartons stay aligned under strap and film.

Paperboard or plastic

Supplier ranges include both paperboard and plastic options; Cordstrap’s page names cardboard and plastic, and notes that the right choice depends on variables such as the application and the type of polyester strap or lashing used.

Point to compare	Laminated paperboard corner board	Moulded or extruded plastic protector
Common form	Long L-shaped strips, often full stack height, cut to length	Short corner pieces or channels placed at strap positions
What suppliers emphasise	Spreading strap pressure along an edge and adding stability to a stack; the Signode range is made from recycled board	Protecting both cargo and strap, as Cordstrap describes its cardboard and plastic range
Questions to ask	How does the board behave if it is stored or shipped damp? Which leg sizes and thicknesses are offered?	Is the protector itself free of sharp edges? Does it fit the strap width? Can it be reused in a return loop?
What to watch for on the line	Boards sliding before the first strap holds them; crushed boards at strap positions	Pieces moving away from the strap path if they are too small or not held

The table describes general differences to discuss with a supplier, not ratings. Ask for the supplier’s own data for the exact product.

Steel strap on sharp-edged loads deserves a note. PAC Strapping Products recommends steel strap for heavy loads with sharp edges. Even then, the goods may still need protection from the strap, so the protector question does not disappear when steel is chosen.

What to put on the specification

“Corner protectors” is not a specification. A useful line names:

• Profile: L-shaped angle, U-shaped channel, or a short corner piece.
• Leg size and thickness: stated in millimetres, with the tolerance the supplier can hold.
• Length: full height, a fixed short length, or cut to order.
• Material: paperboard, recycled content if relevant, or plastic type.
• Exposure: indoor only, covered yard, or wet conditions on the route.
• Strap interface: the strap width and type it will sit under, so the protector is wide enough for the strap path.
• Quantity per unit load: so purchasing can convert loads into protector orders.

Keep the protector reference in the same approved packing record as the strap, closure and tool. If the protector changes, review the arrangement as you would for a change of strap.

Placement and the order of operations

A protector only works where it is placed, and in the order it is applied. A few rules help:

1. Place before tensioning. The protector must be under the strap when tension is applied, not pushed in afterwards.
2. Centre the strap. The strap should sit on the protector across its full width, not on its edge.
3. Cover every contact edge. Where a strap turns over a top corner and a bottom edge, both need attention.
4. Hold long boards in place. Full-height boards can be held by the first strap or by film before the remaining straps go on.
5. Check after tensioning. Look for protectors that have rotated, crushed or moved away from the strap.

Write these steps into the packing instruction with photographs of a correctly finished load. The sharp edges guide explains how to map contact points before choosing a protector.

Receiving and stock control

Protectors are bulky and easy to substitute. On receipt, check profile, leg size, thickness and length against the order. Store paperboard boards flat and dry, and ask the supplier how moisture affects the grade you buy, so that storage matches the conditions the board was chosen for.

Matching the strap and closure

YAKU lists PET strap, woven strap, sheet metal clips and galvanized wire buckles; YAKU does not offer edge protectors as a product family. Describe the load, protector and tool in use through the enquiry page so the strap and closure discussion starts from the full arrangement.