Stretch fólie pro balení cívek: Balení drátěných cívek a PVC trubek

Shrnutí Stretch film for coil packing, for wire coil and PVC pipe coil wrapping alike: for eye-through coil wrapping we run LLDPE stretch film on a 50 mm core, 100–150 mm wide, with a roll OD up to 450 mm on our FPS-300. Our standard film is 25 micron, thicker 32–50 micron film also runs, and VCI film is added against rust. A worked example calculates film length and weight per coil.

Obsah

What the film has to do on a coil

On an eye-through wrapper, the film goes through the coil eye and round the outside on every turn of the ring. It has to cling to itself, follow the sharp edges at the ID and OD, and stay tight while the coil turns on the rollers.

Our vertical wire coil wrapper stands the prestressed steel wire coil on edge, set in a floor pit so the coil rolls in at floor level. Drive rollers turn the coil while the ring lays white wrap through the eye, and the wrapped coils wait beside the machine for dispatch. On a wire coil the film has to bridge the gaps between wire turns and hold where the coil sits on the rollers.

Our hose and pipe coil wrapper works the other way up: a PVC pipe coil lies flat on support rollers and the ring wraps film through its eye.

A plastic pipe coil is light and soft, so the film needs enough tension to hold the turns together but not so much that it squeezes the coil out of round.

Film type: LLDPE, PE, PVC, HDPE or paper

Our FPS-300 takes PVC, LLDPE, PE, HDPE and paper. For most steel and wire coils, LLDPE stretch film is the default. It stretches, clings and closes the package against dust and water.

Paper is used where the coil surface must breathe or must not touch plastic. On our FPS-500 two material rolls can run at once, for example LLDPE with VCI film.

Roll size: it has to fit the ring

The film roll rides on the turning ring and passes through the coil eye. So the roll size is set by the machine, not by the film supplier. On our FPS-300 the roll must match this table.

Film roll item FPS-300 value
ID jádra 50 mm
Vnější průměr válce 100 – 450 mm
Šířka filmu 100 – 150 mm
Materiály PVC, LLDPE, PE, HDPE, paper
Míra překrytí 10-90%
Rozsah cívek 508–610 mm ID, 600–1,200 mm OD, 100–300 mm wide, 20–1,000 kg

A wider roll covers the coil in fewer turns, but it has to pass through the eye. For a small coil ID, ask us before ordering wide film.

Tloušťka

Our standard coil wrapping film is 25 micron. We have also confirmed that film of 32–50 micron runs on our coil wrapping machines. Thicker film resists tearing on sharp coil edges and rough handling, but it costs more per coil.

Start with the standard film and go thicker only if edges tear or the package opens in transport.

VCI film against rust

VCI film releases a corrosion inhibitor inside the package. Use it when coils travel by sea or sit in humid storage. A common build is a VCI layer next to the steel and LLDPE stretch film outside, which the FPS-500 lays from its two rolls in one cycle.

Overlap and layers

The overlap rate on our FPS-300 is adjustable from 10% to 90%. At 50% overlap, every point of the coil is covered by two layers. Higher overlap adds layers and film, so it suits export packing.

Overlap is tightest at the coil ID, where the turns crowd together, and loosest at the OD. So set it for the OD.

Worked example: film length and weight per coil

A plant wraps coils of 1,200 mm OD, 508 mm ID and 300 mm width with 120 mm LLDPE film at 50% overlap. These are illustrative customer figures. The coil fits the FPS-300, which takes 600–1,200 mm OD and 100–300 mm width.

Dráha filmu na otáčku. One turn goes through the eye, round the outside and over both faces. The radial depth is (1,200 − 508) ÷ 2 = 346 mm. So one turn is 2 × 346 + 2 × 300 = 1,292 mm, about 1.29 m.

Number of turns. At 50% overlap each turn advances 120 × 0.5 = 60 mm at the OD. The OD circumference is π × 1,200 = 3,770 mm. So the ring makes 3,770 ÷ 60 = 63 turns.

Délka filmu. 63 × 1.29 = 81 m of film lies on the coil.

Film weight. LLDPE is about 920 kg/m³. At 25 micron, 81 m of 120 mm film is 0.000025 × 0.12 × 81 = 0.000243 m³. That is 0.000243 × 920 = 0.22 kg. At 50 micron it doubles to 0.45 kg.

Protáhnout se. The roll pays out less than 81 m, because the film is stretched as it goes on. Film off the roll = 81 ÷ (1 + s), where s is your stretch ratio. Your film supplier states the stretch the film is rated for, and we set the tension on the machine to suit it.

Kontrolní seznam pro výběr: co nám poslat

  1. Vnější průměr, vnitřní průměr, šířka a hmotnost cívky.
  2. Coil material and surface: bare, oiled or painted.
  3. Transport: truck, rail or sea.
  4. Film type and thickness you use now.
  5. Whether you need VCI film or paper.
  6. Cívek za hodinu.

Bezpečnost a EN 415-10

For CE markets we follow EN 415-10 as the reference, with a risk assessment to ISO 12100. The main hazard is the turning ring with the film roll. Others are the carrier rollers and the film cutter.

Load film rolls only with the ring stopped. Keep guards closed while the ring turns, and use the emergency stop to clear a film break.

Často kladené otázky k inženýrství

Q: Can we use our own film? A: Yes, if the roll fits the ring: 50 mm core, roll OD up to 450 mm and 100–150 mm wide on the FPS-300.

Q: Should we just use thicker film? A: No. 25 micron is our standard. Go to 32–50 micron only where edges tear or the coil travels hard.

Q: Can the machine wrap film and VCI together? A: Yes. The FPS-500 runs two material rolls at once, such as LLDPE and VCI film.

Otázka: Podle jakých norem stavíte? Odpověď: EN 415-10 jako naše reference CE s posouzením rizik dle ISO 12100.

Další krok

  1. Email your coil size, transport route and current film na info@fhopepack.com.
  2. Odpovíme s návrhem do 24 hodin, with the machine, film type, thickness and overlap.
  3. We send a film test plan for your coils.

Zdroje

  • Specifications: FHOPE FPS-300 and FPS-500 product pages; film thickness from our own quotations
  • Videa o strojích: prestressed steel wire coil wrapping a PVC pipe coil film wrapping na YouTube
  • Film length and weight: our worked example, illustrative coil figures
  • Normy: EN 415-10 (balicí stroje, obecná bezpečnost); ISO 12100:2010

Naposledy zkontrolováno: 17. 10. 2026

Související příspěvky

Rezervujte si hovor
Rezervujte si hovor