Executive summary
Small-diameter steel tubing used in furniture, display racking, and automotive components frequently features polished, chrome-plated, or powder-coated surfaces that scratch when tubes contact each other inside a bundle. Our automatic steel tube bagging machine automates the individual protective sleeving process. Tubes are separated one by one from an inclined gravity buffer rack, fed through driven non-marking pinch rollers, and pushed through a continuous film-forming and heat-sealing collar. Sealed, fully sleeved tubes discharge automatically at speeds synchronized with modern cold roll-forming mills.
The packaging system automates the transition from raw mill production to isolated protective sleeving. An inclined multi-arm accumulation rack indexes tubes through a pneumatic singulation escapement onto a high-friction timing belt conveyor. At the feed station, a geared servo drive powers dual polyurethane-coated pinch rollers equipped with overhead pneumatic downward-pressure cylinders. Low-friction V-groove guide rollers align the tube along its center line, driving it smoothly through the film collar where roll-fed barrier film is folded and longitudinally sealed around the moving tube.
Table of Contents
- Line layout
- Machine sequence
- Machine data
- Feeding small tube
- Matching the tube mill
- Selection checklist
- Safety
- Engineering FAQ
- Next step
- Related reading
- Sources
Line layout
The continuous packaging system consists of three modular functional zones:
- In-feed & Singulation Section: An inclined storage table buffers mill batches. Pneumatic indexing arms isolate bundles into single tubes, transferring each workpiece to the central in-feed line without surface impact.
- Forming & Heat-Sealing Station: A precision former folds flat sheeting into a continuous cylindrical sleeve. A constant-temperature heating block seals the longitudinal seam, while an integrated guillotine cross-seal unit separates individual bags.
- Out-feed & Accumulation Conveyor: A motorized roller conveyor transports the sleeved tubes downstream onto a padded collection cradle for strapping, crating, or automated master bundling.
Machine sequence
- Mill bundles or crane drops load batches of tubes onto the inclined buffer storage rack.
- The pneumatic escapement indexer releases a single tube onto the motorized in-feed conveyor.
- Polyurethane pinch rollers clamp the tube circumference and drive it forward at the set line speed.
- Film is tension-unwound from the roll, guided over the forming collar, and welded along the longitudinal edge by an adjustable PID constant-temperature sealing bar.
- Optical sensors track the trailing tube end, triggering the transverse cross-seal and cutoff blade within the designated gap.
- The out-feed belt accelerates the sleeved tube onto the collecting table, clearing the sealing zone for the next workpiece.
Machine data
| Specification Item | Standard Configuration | Optional Customization |
|---|---|---|
| Compatible Packaging Film | BOPP, HDPE, LDPE (Plain or Printed) | Micro-perforated VCI anti-rust film |
| Film Roll Dimensions | OD 100–200 mm, Core ID 75 mm (3.0 in) | Heavy unwind roll stand up to OD 300 mm |
| Film Thickness | 30–60 µm (Single-wall) | 25–80 µm reinforced films |
| Workpiece Length Range | 6,000 mm (Standard) | 2,000–12,000 mm extended chassis |
| Tube Outside Diameter (OD) | 9.5–50 mm | Non-round profiles within 50 mm cross-section |
| Linear Bagging Speed | 10–50 m/min (Inverter / Servo controlled) | Synchronized to high-speed mill speeds |
| Pneumatic Supply | 0.5–0.7 MPa (5–7 bar), clean dry air | Integrated water-separator regulator |
| Electrical Power Rating | 380 V, 3-Phase, 50/60 Hz (3.5 kW) | 208 V / 220 V / 480 V regional standards |
The main drive runs via an industrial PLC linked to variable-frequency drives (VFD) and a color touchscreen HMI. Buffer rack width, support arm spacing, and out-feed discharge directions are engineered to your plant floor footprint and confirmed during technical sign-off.
Feeding small tube
Small-diameter thin-wall tubing (down to OD 9.5 mm) exhibits high lateral flexibility. Pushing these tubes from the rear end over long distances causes Euler column buckling, resulting in line jams and damaged guide dies.
To eliminate flexural deformation, the machine uses a pull-through drive principle:
- Polyurethane Pinch Clamping: Dual high-traction rollers (Shore A 75–80 durometer) grip the leading section close to the forming station, pulling the tube straight along the centerline.
- Pneumatic Float Hold-Downs: Counter-balanced pneumatic cylinders maintain steady downward force regardless of slight tube runout, preventing thin tubes from lifting or vibrating.
- Non-Marking Contact Surfaces: All guide rolls, escapement stops, and bed rollers are clad in high-grade polyurethane or ultra-high-molecular-weight polyethylene (UHMW-PE) to safeguard mirror-polished, anodized, or electroplated finishes.
The forming die rapidly adjusts across the full 9.5–50 mm OD envelope. Symmetric hollow profiles—including square, oval, and rectangular aluminum extrusions—run within the same system provided the maximum diagonal fits inside the 50 mm forming collar.
Matching the tube mill
Maintaining uninterrupted mill operation requires matching line throughput with an operational buffer. Calculate output rates using standard kinematics:
Tubes per minute from the mill = Mill speed ÷ Cut length
Tubes per minute in the bagger = Bagging speed ÷ (Cut length + Tube gap)
Example calculation:
- A continuous roll-forming mill running at 40 m/min cutting 6.0 m pipe produces:
40 ÷ 6.0 ≈ 6.67 tubes/min - Setting the packaging line to 45 m/min with a 0.5 m cycle gap between ends gives:
45 ÷ (6.0 + 0.5) = 45 ÷ 6.5 ≈ 6.92 tubes/min
The 0.5 m gap provides approximately 0.66 seconds of travel window at 45 m/min, sufficient for the constant-temperature pneumatic cross-seal mechanism to complete its stroke and return. The packaging machine runs at approximately 104% of mill speed, clearing each tube ahead of the cut-off cycle. The inclined storage rack absorbs momentary mill cut-off surges or coil changeovers.
Selection checklist
To configure your equipment order, confirm the following technical parameters:
- Tube Cross-Section Dimensions: Minimum/maximum outside diameter (OD) and minimum wall thickness.
- Cut Length Range: Standard cut lengths and allowable length variations.
- Surface Treatment: Cold-rolled black, hot-dip galvanized, mirror-polished stainless steel, chrome-plated, or powder-coated.
- Mill Production Speed: Target operating line speed (m/min) and average pieces per minute.
- Film Specifications: Material type (BOPP vs. PE), film thickness (µm), and plain vs. registered branded print.
- Downstream Integration: Manual pack-off, automatic hex-bundling station, or master wooden box packing.
Safety
All packaging systems are built in compliance with international industrial safety mandates:
- Risk Assessment: Designed in conformance with EN ISO 12100:2010 principles.
- Packaging Machinery Safety: Built to EN 415-10 specific safety criteria for forming and wrapping machinery.
- Electrical Architecture: Integrated according to EN 60204-1, featuring IP54-rated control enclosures, emergency stop circuits (Category 0/1), and 24 V DC operator control safety voltages.
- Mechanical Guarding: The in-feed pinch rollers and cross-cutting zones represent mechanical nip and shear points; they are enclosed within sheet-metal guards fitted with safety interlock switches that trigger dynamic braking upon access.
Engineering FAQ
Q: Can the machine handle tubes coated with light anti-rust or mill vanishing oil? A: Yes. The drive system utilizes oil-resistant polyurethane rollers that retain frictional tractive effort. Because the longitudinal and end seams are created film-to-film via heated sealing blocks, light surface oil on the tube exterior does not contaminate the polymer weld. Temperature controls are adjustable on the HMI (±1 °C) to suit BOPP or PE films without burning or generating smoke.
Q: Can the packaging machine run non-ferrous tubes and structural aluminum profiles? A: Yes. Aluminum extrusions, brass tubing, and thin-wall copper pipes can be packaged without modification, provided the outer cross-sectional envelope remains within the 50 mm diameter boundary and the profile weight does not exceed conveyor limits.
Q: Is manual stepping available for operator setup and blade replacement? A: Yes. The control console includes a keyed Selector switch allowing full manual jog mode. Operators can jog pinch rollers, test cross-cut knife strokes, and calibrate seal temperatures independently before engaging automatic sequencing.
Next step
- Email your tube OD range, wall thicknesses, standard lengths, and mill speeds to info@fhopepack.com.
- Our engineering team will generate an envelope proposal specifying feed spacing, former collar sizes, and factory layout drawings.
- Receive a formal proposal and turnkey quotation within 24–48 hours.
Related reading
- Automatic tube and profile bagging machine (product)
- Automatic steel pipe bundle packing line (product)
- Tube bagging machine
- Automatic aluminum tube bagging and stacking line
Sources
- FHOPEPACK Engineering Documentation: Automatic Small-Diameter Tube and Profile Bagging Systems
- EN ISO 12100:2010: Safety of machinery — General principles for design — Risk assessment and risk reduction
- EN 415-10: Safety of packaging machines — Part 10: General requirements
- EN 60204-1: Safety of machinery — Electrical equipment of machines — Part 1: General requirements
Last reviewed: 2026-10-20
