Relocating Lines: What Labeling Equipment Manufacturers Advise
Expert troubleshooting guide for relocating and installing labeling lines. Fix web tension, VFD noise, and steam tunnel errors post-move.
Relocating a high-speed labeling line—whether a rotary Krones Autocol cold-glue system, an inline Herma 500 series pressure-sensitive applicator, or a Videojet print-and-apply unit—introduces severe mechanical, thermal, and electrical variables. When manufacturing equipment relocation and installation is executed poorly, the resulting downtime on a high-speed beverage or pharmaceutical line can exceed $10,000 per hour. This guide details the exact troubleshooting protocols and repair adjustments required to resolve the most common post-installation failures reported by OEMs.
Pre-Relocation Diagnostics: Establishing the Baseline
Before unbolted a single anchor, maintenance teams must capture the machine’s operational baseline. When PMMI (The Association for Packaging and Processing Technologies) safety and installation standards are followed, technicians document specific servo torque values and encoder pulse counts. For pressure-sensitive applicators, record the exact web tension (measured in N/m) at the unwinds, and the stepper motor current limits for the peel plate assembly. Without this data, post-installation troubleshooting becomes a process of blind guesswork.
Troubleshooting Pressure-Sensitive Web Tension Post-Move
The most frequent failure mode after relocating inline pressure-sensitive labelers (such as Quadrel or Herma systems) is web tracking deviation and telescoping. During transit, forklift mast tilt or uneven floor leveling at the new site can subtly bend the unwind shaft or misalign the dancer arm pivot.
| Symptom | Root Cause (Relocation Specific) | Calibration Fix |
|---|---|---|
| Web Telescoping (Roll shifting side-to-side) | Unwind shaft bent by 0.5mm+ during rigging; dancer arm pivot binding. | Mount dial indicator on unwind shaft. If runout exceeds 0.05mm, replace shaft. Clean and re-lubricate dancer arm pivot bearings. |
| Label Wrinkling on Application | Peel plate angle shifted due to mainframe torsion from uneven anchor bolting. | Use a digital protractor to reset peel plate to exactly 15-18 degrees relative to the product conveyor. Shim machine feet to eliminate frame twist. |
| Intermittent Web Snaps | Brake tension set too high (compensating for a misaligned idler roller). | Verify idler roller parallelism with a laser alignment tool. Reset brake tension to 1.5 - 2.2 N/m for standard PP films. |
Rotary Cold-Glue Labeler Cam Timing & Vibration Damage
Rotary labelers rely on precise mechanical cam boxes to synchronize the gripper cylinders with the glue roller. Heavy vibration during transport, or dropping the machine base even slightly, can knock the main drive shaft out of phase. If your Krones or KHS rotary labeler is applying labels 5mm to 10mm off-target post-installation, the cam timing has likely slipped.
Step-by-Step Cam Resynchronization
- Rotate the main carousel to Top Dead Center (TDC) using the manual handwheel.
- Mount a magnetic dial indicator on the machine base, resting the probe on the gripper pad.
- Loosen the main drive coupling bolts (do not remove them entirely).
- Adjust the carousel until the dial indicator reads the exact TDC offset specified in the OEM manual (typically 0.00mm to 0.02mm variance).
- Torque the coupling bolts to the manufacturer's specification (usually 45-60 Nm) using a calibrated torque wrench, re-checking the dial indicator after each bolt is tightened to ensure the shaft did not pull out of phase.
Shrink Sleeve Steam Tunnel Pressure & Condensation Faults
Relocating a shrink sleeve tunnel (such as a Krones Accutek or ZND steam tunnel) to a new facility almost always results in thermal distribution errors. The new facility's steam boiler pressure, water chemistry, and piping layout differ from the original site.
According to OSHA material handling and facility safety guidelines, modifying steam delivery systems requires strict adherence to pressure vessel and piping codes, but from a process perspective, the labeler's steam manifold is where the real troubleshooting happens.
The Condensation Drip Defect: If you notice water spots on the shrink film or uneven shrinking (dog-ears at the bottom of the sleeve), the steam is carrying too much condensate. This happens when the relocated steam lines lack proper drip legs or when the facility's steam pressure exceeds the tunnel's optimal 15-20 PSI operating range, causing violent flashing inside the manifold.
The Fix: Install a 5-micron particulate filter and a high-capacity thermodynamic steam trap within 3 feet of the tunnel inlet. Verify the pressure using a gauge at the manifold itself, not at the boiler. If pressure drops below 12 PSI at the manifold during high-speed runs, increase the supply line diameter from 1/2-inch to 3/4-inch to reduce flow restriction.
Resolving VFD Ground Loops and Encoder Pulse Loss
When a labeling line is moved across a plant or to a new building, it is tied into a different electrical ground grid. This frequently introduces ground loops that inject high-frequency noise into the Variable Frequency Drives (VFDs) powering the conveyors and applicators. The National Electrical Manufacturers Association (NEMA) provides extensive guidelines on VFD installation, but the most common symptom on a labeling line is the HMI throwing a "Label Gap Error" or "Web Break Fault" despite the web being intact.
This occurs because the electrical noise is corrupting the 5V TTL quadrature signals from the web encoder (such as a Sick or Heidenhain optical encoder). The PLC misses encoder pulses, miscalculates the web speed, and triggers a fault.
Electrical Troubleshooting Protocol:1. Inspect the encoder cable. It must be a twisted-pair, shielded cable.
2. Ensure the cable shield (drain wire) is grounded at the PLC/Drive end only. If it is grounded at both the encoder and the drive, you have created a ground loop antenna.
3. If noise persists, access the VFD parameters and lower the carrier frequency (switching frequency) from 4 kHz to 2 kHz. This reduces the high-frequency harmonic noise radiating into adjacent signal cables.
Conveyor Pitch Matching and Transfer Plate Geometry
Integrating a relocated labeler into an existing conveyor line often creates a physical mismatch at the infeed and outfeed transfer plates. If the labeler's internal conveyor is 0.5mm higher or lower than the facility's main conveyor, products (especially lightweight PET bottles or vials) will catch on the dead plate, causing tipping and crushed containers.
For products under 50mm in diameter or with a high center of gravity, standard UHMW (Ultra-High-Molecular-Weight polyethylene) dead plates are insufficient post-relocation. The repair requires installing powered transfer rollers or a motorized transition belt bridging the gap. Ensure the pitch (the distance between product pushers or lugs) of the incoming conveyor matches the labeler's infeed screw timing. If the pitch is mismatched, the infeed screw will violently strike the products, a failure mode that destroys the screw's polyurethane coating within hours of operation.
Decision Matrix: When to Call the OEM vs. In-House Maintenance
Not all post-installation errors should be handled internally. Use this framework to decide when to escalate to the manufacturer's field service engineers.
- In-House Maintenance: Conveyor height alignment, steam trap replacement, VFD grounding, peel plate angle adjustment, and sensor realignment.
- Call the OEM: Main carousel cam box resynchronization (requires proprietary jigging), servo drive firmware corruption post-power surge, and replacement of the main rotary bearing if rigging damage is suspected. Attempting to press out a main rotary bearing without OEM hydraulic tooling will void the machine's warranty and risk catastrophic housing fracture.
