The Cost of Hot Melt System Cleaning & Maintenance

For end-of-line packaging applications, production issues typically dictate most hot melt glue system maintenance efforts. Fighting to keep adhesive char at bay for systems with a tank-based melting process is a constant battle. These reactive maintenance events often result in costly downtime and create a “fire sale” situation – where maintenance managers are overnighting the needed replacement parts and potentially flying-in equipment experts to get packaging lines back up and running.

If the system has been neglected for too long, a simple system purge and filter replacement may not be enough. It is not uncommon for a hot melt glue system to require a complete disassembly. Individual parts are either replaced or submerged in hot oil to remove char located in dead corners of the parts that can’t be flushed. Once completed, the system will be reassembled with replacement seals and recalibrated.

Developing a proactive maintenance process for hot melt equipment is the best approach for facilitating maximum uptime. Larger facilities with 10-15+ lines must rely on a solid proactive maintenance process to keep their lines running. These facilities often have dedicated personnel on staff to clean and purge hot melt systems on a predetermined cycle.

While there are significant costs associated with a reactive maintenance event, there are still measurable costs associated with proactive hot melt maintenance. For each system purge, there are multiple cost elements:

• Wasted adhesive from hot melt purge – up to 10 lbs. for larger tank-based systems
• Cleaners (paraffin wax, peanut oil, vegetable oil) - removes char stuck to walls of melters, hoses and applicators
• Downtime - systems may require multiple cycles with new cleaner to adequately remove adhesive char
• Replacement parts – includes new filters, nozzles and seals
• Labor – system cleaning personnel on-staff or a specialized 3rd party resource

These cleaning events will also take time and require the entire line to be down. On average, it takes up to 4 to 6 hours to effectively purge a tank-based hot melt glue system, clean the tank, hoses and applicators and change filters, seals and nozzles. While these costs add up, they are still much less than the costs of a reactive maintenance event.

It is always recommended to follow the suggested maintenance schedule suggested by the equipment manufacturer. However, the frequency of hot melt system maintenance often depends on the specific application, production environment and hot melt equipment in the line. 

For example, a US-based flea/tick carton manufacturer using a tank-based hot melt system requires a system purge every 3 months. This facility is only running on a four-day workweek and processing a relatively low (600 pounds of glue through system per year). The facility is also a clean environment with no excessive paper dust or other significant contaminants. Without the typical contamination factors, it is likely that the system itself and the adhesive temperature control are creating this maintenance frequency scenario.

One of the best ways to develop and maintain hot melt equipment is to stay informed of maintenance options and best practices. In addition to equipment manufacturers and trade publications, staying connected to other facilities within your organization can provide helpful insights into process improvement and new equipment options.

Even within the same company, facilities can use different equipment to perform the same end-of-line packaging applications. In some cases, these facilities could be less than a mile away from each other or the corporate headquarters. While plant managers may share some information with each other, it may not be communicated to the engineering or maintenance personnel at the plant level to help prevent maintenance issues that increase cost and decrease productivity and profitability.