Preparing Molten Products for the Shelf

Molten products such as candles, chapstick, deodorant and other items that are liquified for packaging can offer challenges to those putting such items on the shelf. The obvious challenges, of course, are liquiefying a solid or semi-solid product and then allowing it to cool while remaining structurally sound. There are a few machines that are unique to molten packaging lines or at the least seen most often on such lines.


The main difference between a molten filler and a regular filling machine revolves around temperature control. When filling a solid as a liquid, the product must be kept at a hot, and often steady, temperature. Allowing a molten product to cool obviously allows it to solidify, and it's not hard to imagine the issues with a product that turns from liquid to solid in a tank, pipe, tubing or nozzle. So the product must be kept at a constant temperature throughout the fill process, tank to container. Overheating a product may also lead to changes in viscosity or even damage to the product upon cooling down. So temperature and temperature control are crucial to successfully packaging any molten product using a liquid filler.


Once filled at a high temperature, the product must be allowed to cool, and this process can not always be done quickly. Cooling to fast can cause damage to containers, inconsistent fills and other issues. For this reasons, cooling conveyors will often be built as serpentine conveyors, conveyor towers or even a combination of both to allow for extra time for cooldown. Where a speedy cooldown is possible, a fan system may be added to a shrouded conveyor to allow for quicker temperature drops and product solidifying. In other words, cooling conveyors can be designed in many different ways, but all simply allow the product to cool and solidify after filling.


Reheat stations provide another solution to quick cooling that may result in uneven solidifying. Using a reheat station allows a product to, as the name suggests, be reheated and once again liquified, only to settle evenly a final time before further packaging processes, such as capping or labeling, occur. Reheat stations may be used simply for aesthetic purposes where molten products are packaged in see-through containers, such as candles in glass jars, where an even line is more pleasing to the eye.


Once filled and properly cooled, molten products are basically packaged just like any other product. The capping machine will depend on the type of closure being used on the package, but typically no special equipment or features will be necessary. The same is true of labeling equipment and other machines. The key words above being "properly cooled". Should a container or product still be too warm upon reaching the capper, labeler or other piece of equipment, issues such as inconsistent capping, wrinkled labels and more may occur. For questions or more information about packaging machinery for Molten Products, contact a Packaging Specialist at Liquid Packaging Solutions today.