Orbital Through-the-Eye Wire Coil Wrapping Machine (FPW-300): Engineering Specification & Selection Guide

Executive summary

Packaging a wire coil requires passing protective film through its core opening (the “eye”) to achieve a complete, hermetic cross-sectional seal. Our orbital wire coil wrapping machine accomplishes this by rotating a shuttle ring through the inner coil diameter while driven cradle rollers rotate the coil around its horizontal axis. The wrapping station is mounted on an automated traversing base that retracts to provide open overhead clearance for crane or forklift loading, then advances into position through the coil center to execute high-speed protective wrapping.

The work cycle secures the coil vertically in an engineered twin-roller cradle driven by a variable frequency motor, while the high-tensile cast-alloy ring rotates inside an interlocking perimeter safety enclosure compliant with EN ISO 14120. Multi-layer industrial stretch film or composite paper wraps the complete cross-section with calibrated radial overlap until the coil is completely sealed against moisture, dust, and transit shifting. The system operates from a standalone floor-mounted control console equipped with a Siemens/Omron PLC, high-resolution HMI touch interface, and a multi-stage optical status beacon.

Table of Contents

• Why wire coils are wrapped through the eye
• What the moving station does
• Machine sequence
• Machine data
• Overlap and cycle time
• Selection checklist
• Safety
• Engineering FAQ
• Next step
• Related reading
• Sources

Why wire coils are wrapped through the eye

Circumferential or belly-only wrapping wraps only the outer cylindrical surface, leaving both side faces and the interior coil bore completely exposed to environmental humidity, condensation, and particulate contamination. Over maritime transit or extended storage, this leads to edge oxidation, rust pitting, and mechanical scuffing.

Wrapping through the eye wraps film through the core opening and over the radial width in a continuous toroidal helix. This provides distinct mechanical advantages:

• 360-Degree Environmental Sealing: Encloses the inner core, outer periphery, and both lateral faces inside an overlapping moisture and dust barrier.
• Radial Clamping Force: The applied stretch tension binds individual wire windings tightly together, preventing strand shifting, “bird-caging,” and telescoping during fork handling or crane lifting.
• Anti-Snag Containment: Secures loose end-tails firmly against the coil body, eliminating hazardous tail-whip and preventing wire snagging on warehouse racks or freight containers.

What the moving station does

Because an orbital ring is a continuous solid structure that must intersect the coil’s core opening, rigid ring systems traditionally caused severe loading bottlenecks. Overhead cranes and C-hooks risked costly collisions with the upper ring segment during drop-in placement.

The FPW-300 solves this through an integrated motorized traversing carriage:

• Retracted Position (Clear Crane Access): The entire orbital ring assembly and its structural chassis traverse backward on precision floor linear guide rails via a gear-motor drive. The roller cradle is left entirely unobstructed from above, permitting fast vertical loading via factory overhead crane, hoist, or counterbalanced forklift.
• Forward Position (Active Engagement): Once the coil is seated and verified on the cradle, the carriage advances forward. The bottom chord of the rotating ring passes clean through the open eye of the coil, aligning the film shuttle trajectory with the center of the coil’s cross-section. Wrapping begins immediately upon confirmation of travel limits.

Machine sequence

1. Loading & Centering: The wire coil is lowered vertically into the polyurethane-lagged twin-roller cradle. The coil axis rests horizontal, while the coil body stands upright.
2. Station Traverse: The operator initiates the cycle from the HMI console. The motorized wrapping station moves forward, threading the ring structure through the coil eye until reaching inductive limit switches.
3. Film Anchoring & Soft-Start: Pneumatic clamp fingers hold the film leading edge. The VFD initiates soft-start acceleration on the orbital ring motor, matching orbital velocity to preset packaging recipes.
4. Dual-Axis Orbital Wrapping: As the ring orbits through the center hole, the cradle rollers rotate the coil slowly about its horizontal axis. Film tension is maintained at 15–40 N via an adjustable mechanical friction brake on the dispenser carriage.
5. Cut and Wipe Tail Seal: Upon completing the programmed rotation count (one full 360° coil revolution plus designated overlap margin), a pneumatic hot-wire or serrated blade severs the film web. An automatic mechanical wipe-down roller presses the tail firmly against the coil surface.
6. Station Retraction & Unloading: The ring returns to home position, the carriage traverses back to clear the workspace, and the sealed coil is hoisted away for shipment.

Machine data

The FPW-300 wire coil wrapper and the FPS-300 steel strip coil wrapper share the same base mechanical architecture. Both utilize identical ring dynamics and traversing station designs, custom-calibrated for round-section wire bundles or square-slit steel coils. Final ring diameter, traversing stroke length, and film carriage brackets are engineered to customer coil dimensions during quotation.

Overlap and cycle time

Achieving an impermeable packaging wrap requires synchronizing the rotational surface speed of the coil cradle rollers with the orbital speed of the wrapping ring.

The effective linear film advance along the coil outer circumference per complete ring revolution is:

Film advance per ring turn = Film width × (1 − Overlap ratio)

The total number of ring revolutions required to cover the coil periphery is calculated as:

Ring turns per coil ≈ (π × Coil OD) ÷ Film advance

Engineering Calculation Example: For a 100 mm film roll running at a 50% target overlap ratio:

• Film advance per ring revolution = 100 mm × (1 − 0.50) = 50 mm
• For a 1,000 mm OD wire coil: Outer circumference = π × 1,000 mm ≈ 3,142 mm
• Required orbital ring revolutions = 3,142 mm ÷ 50 mm ≈ 63 turns

Inner Eye Overlap Crowding: Because the inner diameter (e.g., 508 mm) has an inner circumference of only π × 508 ≈ 1,596 mm, the effective overlap at the inner bore will be significantly denser (approx. 75–80%). Tension brake calibration is critical to prevent film neck-down or localized over-tensioning across the inner coil edge.

The net wrapping phase duration is:

Wrapping time (minutes) = Ring turns ÷ Ring rotational speed (RPM)

At an operating speed of 70 RPM, the net wrapping time is: 63 turns ÷ 70 RPM ≈ 0.90 minutes (54 seconds).

Total cycle time includes traversing advance (8 s), film clamp/cut cycles (6 s), and station return (8 s), yielding an approximate floor-to-floor cycle time of 76–90 seconds per coil. Both ring and cradle speeds are regulated by independent VFDs, allowing operators to change overlap ratios instantly via the HMI without mechanical sprocket adjustments.

Selection checklist

To configure an FPW-300 cell matched precisely to your mill’s production rate, provide our technical engineering team with the following parameters:

1. Coil Dimensional Envelope: Minimum and maximum Coil ID, OD, axial width, and maximum unit weight (kg).
2. Radial Cross-Section Diagonal: Clearance must satisfy: Ring ID ≥ √(Coil Width² + ((OD − ID) ÷ 2)²) + Clearance Margin (min. 150 mm for carriage traverse).
3. Core Material & Surface Hardness: Carbon steel wire, high-conductivity bare copper, galvanized rod, or soft-drawn aluminum (determines roller durometer and tension limits).
4. Packaging Material Matrix: Single-layer LLDPE stretch film, VCI rust-inhibiting film, woven polypropylene tape, or crepe paper.
5. Target Line Throughput: Required coils per hour (determines cycle time and automated pneumatic cut-off integration).
6. Material Handling Integration: Delivery by C-hook crane, fork truck, ram arm, or automated powered roller conveyor.
7. Upstream Processing: Coordination with existing upstream wire compacting machines, coil binding stations, or inline weighing scales.

Safety

Every machine build complies strictly with European safety mandates and global industrial codes:

• EN ISO 12100:2010: Risk assessment and risk reduction architecture across all mechanical sub-assemblies.
• EN 415-10: General packaging machine safety requirements governing rotating rings, traversing chassis pinch points, and web cutting systems.
• EN 60204-1: Electrical equipment safety, including emergency stop circuit integrity (Category 0/1 stops), IP54-rated control enclosures, and proper earth grounding.
• Physical Guarding: The orbital ring and traverse path are enclosed within rigid steel safety mesh screens. Hinged maintenance doors feature dual-channel interlock switches, cutting power instantly to the ring drive upon opening. A high-visibility multi-color stack light indicates station movement, wrapping status, and film exhaustion alarms.

Engineering FAQ

Q: Can the FPW-300 process copper and aluminum wire coils without scuffing the surface? A: Yes. All coil contact points—including both base cradle rollers and lateral support guide rollers—are coated with 10–15 mm of industrial-grade cast polyurethane (Shore A 85–90). This prevents metal-to-metal contact, galling, or work-hardening. Additionally, the film unwind carriage incorporates a precision multi-disc friction brake to wrap soft copper or aluminum coils under gentle, controlled tension.

Q: Is it possible to apply two different wrapping materials in a single automated cycle? A: Yes. The machine can be engineered with an optional dual-material dispenser ring. This configuration allows simultaneous or sequential wrapping of an inner protective layer (such as VCI anti-corrosion film or neutral crepe paper) followed immediately by an outer water-resistant LLDPE stretch wrap layer.

Q: Why does the machine rotate the coil in place rather than rotating the entire station around the coil? A: Rotating the coil on heavy-duty fixed rollers while keeping the ring in a stationary vertical wrapping plane drastically reduces the required physical footprint. It eliminates massive rotating cantilever arms, minimizes mechanical inertia, keeps safety guard enclosures compact, and provides superior coil stability during high-speed rotation.

Next step

1. Submit Coil Dimensions & Line Requirements: Send your coil ID, OD, width range, max weight, and required throughput (coils/hr) to info@fhopepack.com.
2. Receive Engineering Analysis: Our packaging engineering department will calculate your kinematic clearances, optimal ring diameter, and cycle time models.
3. Formal Proposal Delivery: Receive a comprehensive technical proposal, dimensional layout drawing, and competitive commercial quotation within 24 hours.

Related reading

• Wire coil wrapping machine FPW-300 (Product Overview & Specifications)
• Steel coil wrapping machine FPS-300 (Narrow Strip & Coil Packaging Solutions)
• Wire wrapping machine for steel wire or copper wire (Field Video Application)

Sources

• FHOPEPACK Engineering Technical Documentation: Model Series FPW-300 & FPS-300.
• International Safety Directives: EN ISO 12100:2010 (Safety of Machinery); EN 415-10 (Safety of Packaging Machines); EN 60204-1 (Safety of Electrical Equipment).

Last reviewed: 2026-10-20