Executive summary
Our hot roll steel coil strapping machine is a circumferential strapper: it bands the coil round its OD while the coil sits on the coil car, eye horizontal and in line with the handling line. The strapping head comes down from above to the coil surface, so one station covers different ODs. A worked example shows strap positions, about 11.3 m of strap and about 2.3 kg of steel per coil for two bands.
Table of Contents
- Why a hot rolled coil needs OD straps
- The strapping station on the coil car line
- The strapping cycle
- Circumferential or radial strapping
- Worked example: two bands on a hot rolled coil
- Machine features
- Selection checklist
- Safety: EN 415-10 and ISO 12100
- Engineering FAQ
- Next step
- Related reading
- Sources
Why a hot rolled coil needs OD straps
A hot rolled coil is wound under high tension. Once it leaves the coiler, the outer turns want to spring open. A band round the OD holds the tail and the outer wraps, so the coil stays tight on the coil car, in the crane and in storage.
Strapping in line, straight after the coiler, is faster and more even than banding by hand on a hot, heavy coil.
The strapping station on the coil car line
The station is a green frame over the coil car track, with yellow handrails and a raised platform on one side. The coil sits on the car with its eye horizontal, on the centre line of the handling line. Above the coil is the strapping head on a vertical guide. A strap reel at the side feeds the strap, which runs under the coil through the dispenser.
The strapping cycle
- Coil in. The coil car brings the coil into the station and stops it on the strapping position.
- Head down. The strapping head moves down from above until it touches the coil surface. This is how the station adjusts to each coil OD.
- Strap. The strap is fed round the coil, tensioned, sealed and cut.
- Next band. For a second band, the station moves to the next position set for that coil width.
- Coil out. The head lifts and the coil car moves on.
Circumferential or radial strapping
We build two types of steel coil strapper:
| Type | Strap path | Typical use |
|---|---|---|
| Circumferential | round the coil OD | mother coils from hot and cold mills; holds the outer turns |
| Radial (eye-through) | through the eye and over the OD | slit coils and coils that will be lifted by the eye |
For radial (eye-through) strapping lines, our radial type takes steel strap 19–32 mm wide and can apply 2, 3, 4 or 6 straps per coil. Many mills fit both.
Worked example: two bands on a hot rolled coil
Illustrative coil: OD 1,800 mm, width 1,250 mm, two circumferential bands, steel strap 32 × 0.8 mm.
| Step | Calculation | Result |
|---|---|---|
| Band positions | 1,250 ÷ 4 from each edge | ≈ 312 mm and ≈ 938 mm from one edge |
| Strap per band (bare OD) | π × 1.8 m | ≈ 5.65 m |
| Strap per coil (bare OD) | 2 × 5.65 m | ≈ 11.3 m |
| Strap section | 32 mm × 0.8 mm | 25.6 mm² |
| Strap mass per metre | 25.6 mm² × 7.85 g/cm³ | ≈ 0.20 kg/m |
| Strap mass per coil (bare OD) | 0.20 kg/m × 11.3 m | ≈ 2.3 kg |
These are bare-circumference figures. The seal overlap and the strap left in the track add a little per band; that allowance depends on the seal type and is confirmed at quote.
Station cycle (formula). T = t_in + n × (t_head + t_strap) + (n − 1) × t_move + t_out, with n bands. We measure each time on your coil car and quote the station rate from it.
Machine features
Features of our circumference steel coil strapper:
- Strapping position adjustable for different coil widths.
- Automatic adjustment for different coil ODs.
- Recipe storage for coil sizes and strapping steps.
- Successful strapping rate up to 99%.
- Works with different coil cars and handling lines.
- Double-head strap guiding as an option for higher speed.
- Applications: hot rolled, cold rolled, galvanized and aluminium coil.
Selection checklist
- Minimum and maximum coil OD, ID, width and weight.
- How the coil reaches the station: coil car, crane or conveyor.
- Strapping pattern: circumferential, radial or a combination.
- Number of bands and their positions.
- Strap type and size.
- Coil surface temperature at the station. It sets the head protection and whether the coil must cool first; we confirm this at quote.
Safety: EN 415-10 and ISO 12100
Our coil strappers are designed to EN 415-10, with the hazards assessed to ISO 12100. The main risks are the moving coil car, the strapping head coming down, strap whip at cutting and the hot coil surface. The station area is fenced with yellow rails, the operator works from the platform outside the coil path, and the car and head are interlocked so the head moves only with the car stopped.
Engineering FAQ
Q: How does one station handle different coil diameters? A: The strapping head moves down from above until it touches the coil, so it follows the OD of each coil.
Q: Can it strap a coil straight from the coiler? A: Yes, it is built for hot rolled coil on the mill coil car line. The coil surface temperature at the station decides the head protection, so we confirm it at quote.
Q: How many bands per coil? A: Set by coil width; positions are stored per coil size in the recipe.
Q: Which standard applies? A: EN 415-10, with ISO 12100 for the risk assessment.
Next step
- Send coil OD, ID, width and weight and the loading method to info@fhopepack.com.
- Tell us circumferential, radial or both.
- We reply within 24 hours with a station layout and quotation.
Related reading
- Circumference steel coil strapping machine (product)
- Radial steel coil strapping machine (product)
- Roller station for big coil packing with steel sheet covering and strapping
- Automatic circumferential steel coil strapping machine
Sources
- FHOPE circumference and radial steel coil strapping machine product pages
- FHOPE project notes on circumferential and radial strapping
- Our hot roll strapping station shown above
- Worked example: illustrative figures; steel density 7.85 g/cm³
- Standards: EN 415-10; ISO 12100:2010
Last reviewed: 2026-10-18
