Some of the world’s most crucial industries utilize hot melt equipment and hot melt adhesives to accomplish the business that keeps the global economy moving. From food and beverage to appliance manufacturers, mattress manufacturers, paper products, bookbinders, and the packaging industry itself, hot melt adhesive systems are essential to packaging our most important industrial and consumer products. For the most part, these industries utilize a hot melt tank, which precision melts hot melt adhesive to the ideal temperature before pumping it to applicator guns for easy application.

When properly maintained, hot melt adhesive systems can allow your businesses to quickly and efficiently package your most important products. These low temperature melting adhesives bond to a variety of substrates and form a sturdy bond very quickly. Better yet, utilizing hot melt adhesive systems allows you to perform all your package sealing needs with a single approach—reducing waste and lowering your costs.

The Importance of Hot Melt System Preventive Maintenance

Like any other piece of equipment, however, a hot melt system requires preventive maintenance to perform its best. When you develop a regularly scheduled maintenance routine to address your hot melt system, you benefit your operation in a variety of ways, including:

  • Improved efficiency—maintenance can reduce the effects of wear and tear on your hot melt system, which can eventually lead to restricted flow and inaccurate adhesive placement.
  • Minimized downtime—regular maintenance can virtually eliminate common issues that cause downtime and costly losses in production, including charred pots and clogged lines.
  • Increased system life—regularly cleaning crucial elements of your hot melt system reduces harmful stress on pumps, nozzles, and hoses, improving performance and prolonging their life.
  • Improved safety—addressing potential issues with preventive maintenance reduces the need for hasty emergency calls and workarounds, and the unsafe operating conditions they may cause.
  • Reduced costs—the above issues can cost you valuable time, money, and productivity. Addressing issues before they begin with an effective preventive maintenance program will help you reduce these costs.

Your Preventive Maintenance Guide

While your hot melt system makes attention to your hot melt adhesive and packaging needs simple, the system itself comprises multiple components, each of which must receive regularly scheduled maintenance. Without proper maintenance, charred adhesive can build up and lead to a host of other issues within your system, including clogged hoses and filters, and even damaged equipment. In most cases, char results from external plant contaminants mixing with the adhesive, causing oxidation over time.

The affected adhesive will not melt properly, causing it to clump, settle into the tank, and harden into char. As mentioned, char affects your entire system, and regular maintenance is necessary to remove it before it causes system failure. Scheduling maintenance at least every three months or whenever you change adhesives will help keep your system in proper working order.

Components to Address

When crafting your hot melt system maintenance plan, be sure to target all components:

  1. Hot melt tanks. Since char begins in the tank assembly, cleaning your hot melt tank is one of the most essential parts of a hot-melt system maintenance plan. First, shut down your system, and clear away as much of the remaining adhesive as possible. Then, add a purging compound like Saf-T-Purge 200 and re-engage the pressure pump; the purging compound will break up the rest of the remaining adhesive and push the resulting mixture through your machine. Finally, drain any remaining compound.
  2. Gun and tank filters. At least quarterly, when you purge your hot melt tank—though your system may need attention more often—you should also change gun and tank filters. Failure to do so can result in clogged filters and a strain on your system. Check these often for signs of buildup and replace them as necessary.
  3. Pumps. Your hot melt pressure pump is responsible for pushing hot melt adhesive through your system. As a result, issues with clogs and insufficient lubrication can add unnecessary stress on your pump and even lead to premature failure before the end of its lifespan. Lubricate your pressure pump at least twice per year when you are cleaning your hot melt tank.
  4. Hot melt hoses. Each time you clean your hot melt tank, purge your hot melt hoses. Once a purging compound like Saf-T-Purge 200 has broken up as much of the tank char is possible, pump the purging compound through hoses, clearing out the remainder of the hot melt adhesive left behind. Finally, refill your tank with new adhesive and pump through the hoses and into a clear container until no remaining char or compound is present.
  5. Guns and nozzles. While solvents are a very powerful form of cleaner, they can also be used to clean your most delicate components, including guns and nozzles. On an as-needed basis—at least twice per year while cleaning your hot melt adhesive tank—use a cleaner like Melt O Clean to clean the exterior and interior surfaces of your hot melt adhesive guns. Detachable nozzles can be soaked in solvent and purged of remaining adhesive or replaced, as necessary.
  6. Other machine parts and tools. Any remaining machine parts, adhesive tools, and cleaning tools should be cleaned on an as-needed basis. Again, you can use a cleaner like Melt O Clean and a little elbow grease to remove buildup, foreign debris, and char from these components. Keeping all machine parts clean and in proper working order contributes to your hot melt adhesive system’s proper health and optimal operation.

Develop a Maintenance Schedule That Works for You and Your Machinery

While most businesses choose to develop a quarterly maintenance schedule to purge and clean their hot melt adhesive systems, we’d like to note the importance of consulting the official manufacturer’s guidance for your machine. At the bare minimum, you should perform a full system purge twice yearly. Clean or replace filters, nozzles, machine parts, guns, and pumps quarterly, or as your needs dictate.

If you’d like to learn more about scheduled hot melt adhesive system maintenance or how you can reduce char in your system with high-quality Metallocene and low-temperature EVA, APPLIED Adhesives can be your guide. Our extensive inventory of hot melt machine equipment, replacement parts, guns, nozzles, hoses, and more can help you get your operation back on the right track. Moving forward, perform regularly scheduled maintenance with our selection of purging compounds and cleaners.

Need help getting started? Reach out online or call (800) 274-9801 today.

Written by Bob Hamilton