Missing and wrinkled labels on the bottom of food containers and gift boxes? A line upgrade guide for the WZ-129 bottom labeling machine

Missing and wrinkled labels on the bottom of food containers and gift boxes? A line upgrade guide for the WZ-129 bottom labeling machine

On packaging lines for food containers, household product cans and paper gift boxes, bottom labeling is often the bottleneck holding back overall efficiency. Manual turning and labeling costs labor and easily produces wrinkles, missing labels or position drift. How can efficient, flat bottom labeling be achieved without changing the existing line layout? This article explains the process pain points of bottom labeling and provides a corresponding automation upgrade guide.

Process pain points in bottom labeling and the solution

Inline bottom labeling faces several challenges. First, when the product travels face up, its bottom cannot reach the labeling mechanism directly, so conventional processes need a turning mechanism or manual handling, which slows the line. Second, gravity and uneven contact force during bottom labeling easily produce bubbles or creases. In addition, the food and household products industries have strict traceability requirements, and separating labeling from coding adds process steps.

To address these pain points, Wanzhi Automation developed the WZ-129 bottom labeling machine. It uses a recessed labeling head: as material passes above the conveyor belt face up, the mechanism below applies the label automatically. This inline method needs no manual turning and simplifies line layout; limit and positioning structures keep material centered, effectively solving the industry problems of drift and wrinkling in bottom labeling.

WZ-129 technical analysis and parameter advantages

The WZ-129 achieves efficient, stable bottom labeling through several technical optimizations.

First, on the labeling mechanism, the head is installed recessed beneath the conveyor belt, so material conveyed face up has its bottom labeled automatically, removing the turning step entirely. With limit and positioning on the belt, material passes through the labeling zone centered, giving a stable labeling position with error within ±1mm and keeping bottom labels flat without wrinkles.

Second, the machine offers wide capacity adjustment, with labeling speed adjustable between 20-80PCS/min, meeting both small-batch, multi-run sampling and high-volume continuous inline operation.

In addition, to meet industry traceability needs, the WZ-129 supports an integrated coder or inline inkjet printer. Production dates, batch numbers and barcodes are printed on the label surface at the same time as bottom labeling, integrating labeling and coding.

On hardware, the machine handles products up to 300mm wide, and conveying width and positioning structures can be customized to order. The independent touch operation screen provides visual adjustment of labeling speed and label feed length, and programs can be stored for fast changeover. The one-piece stainless steel frame with swivel castors keeps the machine stable during long, uninterrupted production.

Practical tips and applications

When introducing the WZ-129 for a line upgrade, focus on the following selection and operational points:

• Assess size compatibility: Although the machine handles up to 300mm wide as standard, for oversize cartons or specially shaped containers, consult the Wanzhi Automation technical team in advance to customize a widened conveyor and lengthened frame.
• Label material selection: Bottom labeling has certain requirements for label softness and adhesion; we recommend pressure-sensitive material suited to hard flat surfaces so the pressing mechanism achieves a better bond.
• Traceability module integration: If the line must print variable data, specify the type of inkjet printer when selecting so that code legibility matches the labeling speed.

The solution is widely used for bottom marking and labeling in food containers, household product cans, paper gift boxes and wood panels, and is a practical choice for raising the automation level of a packaging line.

FAQ

What can be done when labels wrinkle during bottom labeling?

Wrinkling is usually related to label material that is too thick or uneven pressing pressure. We recommend switching to a softer pressure-sensitive label and fine-tuning the pressing pressure on the independent touch screen to keep the label flat.

How does the machine adapt to products of different widths?

The standard WZ-129 handles products up to 300mm wide. For special sizes, adjust the belt’s limit and positioning structure to center the material; for oversize products, a widened conveyor and frame can be customized.

Can labeling and inkjet coding be done at the same time?

Yes. The machine supports an integrated coder or inline inkjet printer, so production dates, batch numbers or barcodes can be printed directly on the label surface at the same time as bottom labeling.

This article was written by Wanzhi Automation.