Technomelt COOL 250A and Technomelt COOL 500 are the leaders in the new generation of low application temperature hot melt adhesives. These low temperature hot melts are designed to be used at 250°F in the hot melt tank in comparison to the 350°F required for traditional hot melt adhesives. Technomelt COOL 250A and Technomelt COOL 500 are compatible with traditional EVA-based hot melts. However, it is recommended that the hot melt be purged before changing over to prevent any potential problems.
Before starting the changeover, record the current temperature and pump settings, enabling an easy return to the original settings. When draining the system, ensure that the container used to collect the adhesive is suitable for that purpose.
If possible, purge the system with SAF-T PURGE 200 to ensure cleaning and a good start-up.
· Reduce pump pressure to ZERO and press the button on the gun to manually fire the guns and relieve any residual pressure.
· Open the drain valve and increase pump pressure until the adhesive flows from the valve.
· Completely drain the tank, reduce pump pressure to zero, then close the drain valve. Remove contamination from inside the tank and ensure pump inlet mesh is clean. Once satisfied add 2 -3 scoops of Technomelt COOL 250A or Technomelt COOL 500 into the tank. Do not fill the tank.
· Maintain temperature at 330°F - 350° to allow any original adhesive in the system to melt.
· Allow the Technomelt COOL to completely melt in the tank. Once melted, open the drain valve. Gradually increase pump pressure until the adhesive flows from the valve.
· Fill the tank with 2 - 3 scoops of fresh adhesive and allow melting. Set the tank temperature to 250°F (121°C), the guns and nozzles remain unchanged.
· Remove the tank filter assembly and replace or clean if needed. Slowly increase pump pressure and allow it to flow until the adhesive flow is clean.
· Once the adhesive flow is clean, reduce pump pressure to ZERO and refit the filter assembly.
· Add another 2 - 3 scoops of fresh adhesive if required. Keep the pump pressure at ZERO.
· Before purging adhesive through the guns, remove nozzles. Inspect the condition and replace if damaged. Manually fire the gun and allow adhesive in until Technomelt COOL is flowing through the gun. The color should be pale yellow, and the viscosity much lower. Repeat the same procedure for all guns. Once complete, refit the nozzles and purge a small amount through each nozzle to remove any remaining original adhesive.
· If you cannot purge gun safely, allow adhesive to melt in hose and guns and gradually reduce temperatures to 250°F. Top up the tank and allow to melt fully. Reduce hose and gun temperatures to 250°F and allow to cool before continuing. Set the pump pressure to the original setting and adjust as necessary to give the required bead width.