Businesses and industries all over the world use hot melt equipment to speed up and simplify the packaging process. A hot melt tank stores the adhesive at a carefully controlled temperature. When in use, the tank pumps the adhesive through heated hoses to the required location.
Its ease of use and functionality make it perfect for bonding all types of materials for a variety of needs. The melt adhesives work great for both low and moderate temperature applications. They can bond just about anything, are extremely versatile and can be stored for extended periods. As a further bonus, they can be operated in bulk and require little training, which makes them a very cost-effective solution for businesses.
Preventive maintenance for hot melt tanks
Like any piece of hardware, a hot melt tank requires regular maintenance if it is to continue functioning correctly. Performing routine preventative maintenance keeps hot melt equipment at peak performance, with high productivity.
The main issue with hot melt maintenance is the process of charring, which is the oxidization of the hot metal adhesive from prolonged and repeated heating. The charred adhesive will not melt or dissolve, which leads to clogged hoses, filters and damage to the equipment. This is a common problem in a hot melt, which can only be reduced but not eliminated.
The charring in a hot melt takes place when the adhesive begins to degrade and gel. It loses its thermoplastic nature and rate of flow.
Eventually, this gel settles into other areas of the tank and hardens to become char. The char will usually build up in the bottom of the tank around its insulated heating elements. The higher the temperature and the longer the hot melt is on, the faster char will form.
Another cause of char is when contaminants get mixed into the system, such as paper, corrugated dust and other airborne materials from the surrounding environment. Left untreated, char build-up only gets worse and will lead to a breakdown in the system and the whole production cycle.
Char build-up, though, isn’t the only reason service is required. Better maintenance also means better safety.
If a machine suddenly breaks down during use, it can be dangerous trying to repair it while it still contains hot adhesive. Better maintenance improves the longevity of the equipment and protects your investment.
In order to keep a unit in working order, a hot melt tank must be taken offline periodically for servicing.
Downtime can be costly, so it is important to minimize unscheduled downtime with routine maintenance. If you can keep the char build up at a controllable level, the time they need to be taken completely offline can be reduced. Most manufacturers recommend that a hot melt system is cleaned and purged every three months, or each time an adhesive is changed.
Follow these steps each time you run a maintenance check. The maintenance schedule is determined by the type of adhesive you use, outside contaminants and the environment in which you are operating the equipment.
- Check filters and change them on a regular basis.
- On a quarterly basis, check and purge all your hot melt hoses and tanks.
- On a regular basis, clean or replace your nozzle hoses.
You can also reduce char build-up by using low temperature and heating stable hot melt adhesives. It’s also worthwhile to purchase a cleaning kit. The costs are minimal compared with having to replace parts.
How to clean a hot melt tank
Begin by shutting down the machine and clearing away as much adhesive as possible. The solvent will break up the remaining adhesive, but you’ll want to remove as much as you can first.
Next, add your cleaning solvent and turn the pressure pump back on. This pushes the cleaning solvent through the machine and clears out remaining adhesive.
Finally, drain the cleaning solvent out of the system and add new adhesive. Once it reheats, you can put it back in operation.
Get a professional service check
For the best results and greater peace of mind, schedule a professional service and cleaning. Licensed contractors have industry experience, specialized tools and are fully qualified to carry out all servicing and repairs.
Every hot melt equipment manufacturer, such as Astro Packaging, has different guidelines on how their equipment should be serviced. But most recommend a complete hot melt system cleaning twice a year. Professional contractors can get the job done fast and efficiently, so downtime is limited, efficiency is maximized, and safety is maintained.