Slit Coil Stretch Wrapping and Stacking Line: Eye-Through Ring to Gantry Stacker

Executive summary In this 73 s clip, narrow steel coils lie flat on a roller conveyor. A vertical ring wraps each one through the eye in clear stretch film. Downstream, a gantry stacker grips each wrapped coil from the sides and sets it down on the stack. We explain why stacking comes after wrapping, how the stack is built, and which coil sizes the conveyor-fed models cover.

Table of Contents

What the clip shows

The line consists of a powered roller conveyor, a vertical eye-through wrapping ring and an overhead gantry stacker.

  • Wrapping ring: a narrow coil lies flat, eye vertical, on the rollers inside a vertical ring. The ring turns through the eye and lays clear film over the section while the coil rotates.
  • Gantry stacker: further down the line, a blue gantry spans the conveyor. Its carriage lowers vertical gripper arms, which hold a wrapped coil by its outer edge and set it down.
  • Stack at the end: a second camera angle shows a stack of film-wrapped coils, white in this view, on the rollers between guide arms, ready to leave the line.

Small picture-in-picture windows in the corners show other parts of the same plant at work.

Station timeline

Station What happens Clip time
Vertical wrapping ring coil wrapped through the eye in clear film 0–20 s
Gantry stacker gripper arms lower a wrapped coil onto the stack about 24–40 s
Stack outfeed finished stack on the rollers, guide arms at the side about 45–73 s

Times come from frames taken every 3 s, so each boundary is approximate.

Why the coil is wrapped before it is stacked

Slit coils are narrow and their edges are easy to damage. Wrapping each coil on its own, before stacking, has clear benefits:

  • Every coil is sealed through the eye, so it can later be split from the stack without opening the package.
  • The ring only needs to fit one coil width, not the full stack height.
  • Film protects the faces where one coil sits on the next in the stack.

Our coil packing line programs adjust centring, tension and overlap per coil type, so a thin coil and a wide coil get the same film coverage.

How the gantry stacker builds the stack

The stacker in the clip is a gantry over the conveyor with a carriage that moves up and down.

  1. A wrapped coil stops under the gantry.
  2. The gripper arms close on the outer edge of the coil.
  3. The carriage lifts, and the coil is set down on the stack being built.
  4. When the stack is complete, the rollers carry it to the outfeed.

On our automatic coil packing line, the quote form allows up to 6 coils per stack. In the clip the coils are stacked eye to sky. Eye-to-wall packing is also offered, with a different handling station from this gantry; see stretch wrapping and downender stacking. Stack height is chosen with your handling: a forklift, a C-hook or a pallet.

Coil range for conveyor-fed wrapping

From our steel coil wrapper model table, the conveyor-loaded models:

Model Coil ID Coil OD Coil width Max coil weight
FPCA-1000 508 / 610 mm 700–1600 mm 20–400 mm 2000 kg
FPCA-1200 508–610 mm 800–1400 mm 20–500 mm 2500 kg

These widths match narrow slit coils like those in the clip. The model table is a starting point, not a full list; each line is built to the coil range of the project, so the figures can change.

Selection checklist for a wrap-and-stack line

  • Coil ID, OD, width and weight, smallest and largest.
  • Coils per hour from the slitter.
  • Film, paper or woven wrap, and the overlap needed.
  • Stack height, eye to sky or eye to wall, and stack weight.
  • Strapping of the stack (PET or steel strap) and labelling for ERP/MES.
  • How stacks leave the line: forklift, crane or conveyor to the warehouse.

Controls and safety

The standards that apply depend on the destination market. For CE markets, ISO 12100 sets the risk-assessment method and EN 415-10 covers general requirements for packaging machines, which fixes guarding and the emergency-stop arrangement.

The line runs on a PLC with HMI. Guarding around the ring and under the gantry stacker is set in the risk assessment for each layout.

Engineering FAQ

Q: How does the gantry stacker move a coil onto the stack? A: Vertical gripper arms close on the outer edge of the coil, the carriage lifts, and the coil is set down on the stack on the conveyor.

Q: How many coils can go in one stack? A: Our automatic coil packing line quote form allows up to 6 coils per stack, depending on coil weight and handling.

Q: Which coil widths suit conveyor-fed wrapping? A: Our FPCA-1000 covers 20–400 mm and the FPCA-1200 covers 20–500 mm.

Q: Can the stack be strapped after stacking? A: Yes. PET or steel strapping is an option on our coil packing lines, added as a station after the stacker.

Q: Is film the only wrap option? A: No. Film, paper and woven wrap are all options, set by the program for each coil type.

Next step

We size a wrap-and-stack line in three steps:

  1. Submit your layout drawing with the coil range, coils per hour and stack pattern, to info@fhopepack.com.
  2. Receive a proposal within 48 hours, with the wrapper, stacker and conveyor layout.
  3. Book a site survey so we confirm the slitter exit, floor space and the stack outfeed.

Sources

Last reviewed: 2026-10-06