FOAM FACT FRIDAY
Foam Fact #7
Following Best Practices for Long Term Equipment Storage
Makes a Difference
Before leaving your foam or coating equipment for extended length of time, greater than 3 to 4 weeks, without usage it is important to flush the reactive material out of the machine and purge with a quality storage fluid.
To properly flush your equipment, contact your chemical supplier to select the proper urethane grade solvent that will not react with their formulation(s). Typically it will be a Glycol Ether based solvent that is completely moisture free.
While most chemicals will not affect the equipment-wetted parts, they will react to isocyanate used in most foam and coating material formulations. Whatever you use you must be sure to properly dispose of the flushed material in accordance with local jurisdiction requirements.
When flushing your equipment you should remove all filters and screens and place your feed pumps into the flushing solvent. Cycle the proportioner pumps to push the material through the system until the solvent runs clear. Be sure to properly mark your waste container to not mix the “A” with “B” materials, as they may still react even at a diluted state. Clean all filters and screens separately and re-install after flushing.
After the system runs clear after adequate flushing, you should chase the flush material out with a storage fluid. Common storage fluid should be completely moisture free and is typically a plasticizer or oil that will not gel or react with any trace chemical left in the system. Some common plasticizers are Graco’s TSL (Throat Seal Liquid), DOP (Dioctyl Phthalate), Palatinol 711P or other commercially available moisture free plasticizer. Alternatively, some common oils that may be used for long term storage are mineral oil or hydraulic oil. Be sure to properly flush storage materials when recommissioning to be sure the storage material does not cross contaminate the new materials being dispensed.
After filling the pump with storage fluid, now is a good time to stall the proportioner at 1000 psi fluid pressure and examine the entire system for any packing leakage or loose fittings that should be addressed. Correct any situations that may be found.
The system should be stored in temperatures above 20°F.
Note: Read, understand and follow all instruction manuals and warning labels supplied with all equipment. Only trained and qualified personnel should perform repairs on the equipment.
