Coil Build, Spool and Packing: What Wire Buyers Should Specify

A specification sheet usually says coil weight 5-250 kg and stops there. On the shop floor the number that matters is not the weight but whether the coil pays off without stopping the line. Three details decide that: coil weight against the pay-off equipment, coil build, and how the coil is packed for the voyage.

This wire is supplied annealed at 550-750 N/mm2, from 0.15 mm to 12 mm, in coils of 5-250 kg or spools of 1-25 kg. The inner diameter is set to match the customer's pay-off, and coils are layer wound to avoid trapped turns.

Packing is part of the specification, not paperwork. A container crossing a climate zone condenses water on cold metal, and a bright coil wrapped in film alone will show water stains on arrival. VCI paper under the film is what prevents that.

Product Specifications

Three Details to Fix at Order Stage

Coil weight against pay-off equipment

A 5-25 kg coil can run from a simple vertical stand. Above roughly 100 kg the coil needs a pay-off with tension control, because the mass itself creates back tension that a light stand cannot regulate. Buying heavier coils than the line can pay off creates the very stoppages the larger coil was meant to avoid.

Coil build and trapped turns

A layer-wound coil releases wire at a constant rate. A coil with a turn dropped into the layer below will jam at that point, usually mid-shift, and the operator has to cut and rethread. This is a winding discipline, not a material property.

Packing for the voyage

Condensation forms when a container cools overnight and warms again. VCI paper releases a vapour that protects the surface inside the film; desiccant controls free moisture in the same space. For bright annealed wire this is the difference between a clean delivery and a claim.

Applications

Automated lines with tension pay-off

Large coils on spring coilers, mesh looms and wire formers, where a stoppage costs more than the coil.

Multi-size, small-batch production

Spool supply of 1-25 kg for job shops running several diameters in a week, where handling speed matters more than coil size.

Export shipments by sea

Long transit and climate change in one container, where VCI packing and pallet condition decide the arrival state.

Product Advantages

• Coil weight chosen to the line - 5 kg to 250 kg, so the pay-off equipment can be matched rather than overloaded.
• Layer-wound, no trapped turns - the coil releases at a constant rate instead of jamming mid-shift.
• Inner diameter to your pay-off - stated at order stage, so the coil fits the stand or arbor without adapters.
• VCI packing as standard - condensation protection is built into the packing, not added after a complaint.
• Spool and coil from one source - one diameter and tensile basis across both supply forms.
• Traceable lots - heat number on every coil label with mill test report 3.1 on request.

Quality Control

Diameter is measured inline and at coil ends, tensile and elongation are tested per heat per ISO 6892-1, and coil build is checked for layer alignment and trapped turns before packing. Packing weight, film integrity and pallet condition are verified before the container is closed.

Selection and Ordering Notes

1. Give the pay-off equipment type and the maximum coil weight it handles.
2. State the inner diameter and whether a spool or a coil is required.
3. Confirm the transit time and climate, so VCI and desiccant can be specified.
4. Mention any handling limit at destination, such as crane capacity or rack size.
5. Provide sizes and annual volume for a tolerance and packing review.

Send the diameter, coil weight, pay-off type and destination for technical confirmation and quotation.