Hot Melt Labeling System
Palomar Mountain Spring Water, Inc., an independent water bottler in Corona, Calif., wanted to increase production by 50%. The company installed a new polyethylene terephthalate (PET) bottling line that began operating in July 1999. Palomar Mountain Spring Water worked with Priority One Packaging Machinery, Ontario, Canada, and selected a unique labeling system, the Langguth E62 wraparound hot melt labeler, to help meet its production goal.
The Langguth E62 can label all types of containers made from glass, PET or metal, with full wraparound-label application. It can be used for round, as well as square or rectangular containers. The speed range for the various models is from approximately 30 containers per minute to 1,000 containers per minute, depending on the shape and size of the container. The E62 labeler at Palomar Mountain Spring Water primarily labels 1/2-liter PET bottles but can handle a wide range of container types and sizes.
A Unique Glue SystemThe Langguth E62 labeler features a patented, spray-on hot melt glue-application system. The E62 uses a “direct-transfer” system, where hot melt glue is sprayed onto the containers, which then become their own “label-transfer devices” through direct contact with the stacked labels in the magazine. This differs from conventional machines, which apply glue to bottles by silicon rollers that are individually made to suit each container size. This means the rollers must be changed each time a different-sized container is labeled. Although the E62 at Palomar Mountain Spring Water primarily labels 1/2-liter bottles, the unit’s spray-on system affords the bottler flexibility, which minimizes downtime and maximizes production.
The E62 utilizes one Nordson hot melt unit for both the pick-up and lap-gluing operations. The hot melt unit is mounted outside the machine guarding to allow for easy access. With conventional machines, the hot melt tank is mounted inside the machine guards, which means the operator must reach through the guards to load glue. The E62 features a nonrecirculating glue system. The glue is heated in three stages – in the tank, in the hoses and in the applicator heads – to ensure that no burning or cold spots develop. This completely closed, nonrecirculating system helps to avoid contamination by product or dust. Cleaning is also greatly reduced by the absence of recirculating hot melt tanks.
The firing times of the application heads are easily adjusted from the control panel via the programmable logic controller (PLC), with individual controls for pick-up and lap gluing. The machine is manufactured with a sufficient number of spray nozzles for the pick-up gluing to cover the height of the full range of bottles to be labeled. Each nozzle can be turned on and off from the control panel to suit various label sizes. Each nozzle is equipped with an annular outer ring that emits preheated air, which makes the discharged glue spin to a spiral pattern when applied to the container. This results in significantly less hot melt required for each container. In fact, the E62 hot melt labeler uses 30% less glue than traditional cut-and-stack labeling systems. This has led to significant savings for Palomar Mountain Spring Water’s bottling operation.
The lap gluing is done by a lap bar that incorporates a number of small nozzles. The lap-bar assembly is pneumatically controlled to ensure that it makes contact with the labels only when a container is present, thus avoiding label burning and contamination. When containers are present, a preselected amount of glue is pumped through the nozzles as the labels slide across the lap bar.
The Container-Handling SystemThe Langguth E62 uses a conventional in-feed/discharge system, where the containers are spaced by a feed worm, fed into the in-feed star and guided onto the container platforms and turret. This is where the conventional system stops. The E62 container table is designed with a separately driven bull gear, which drives the container platforms from underneath the turret. By a simple adjustment on a variable-speed gearbox, the turning ratio of the container in relation to the turret can be changed. This completely eliminates the need for belt and/or pulley changes when changing from one container diameter to another.
The container platforms can furthermore be equipped with a cam-controlled clutch, which allows for labeling square or rectangular containers, as well as applying a date code in a predetermined area of the label.
The E62 is also equipped with a fully adjustable label magazine that accepts all label sizes. It is also equipped with scales or digital readouts on all adjustment points, as well as a complete setup chart for each container size to facilitate changeover.