This case history covers a system built for a major aerospace company that was mandated by state and local regulations to reduce VOC output and dependence upon high VOC solvents. It was initially thought to be a very difficult phase out to complete without using a vapor degreaser, especially in the removal of masking wax. Masking wax is a thick substance that dries to a hard consistency on areas of parts not safe (or required) to come into contact with aggressive acidic metal strippers. Traditionally, the use of a vapor degreaser in this procedure removed the wax coating nicely, in a short 20-45 minute cycle.
Testing of a new alternative low VOC wax removing solvent was successful. The product was heated to 180 degrees Fahrenheit in an immersion process. To obtain Air Force approval to change the old operating procedure three full scale wax stripping tests where performed in RAMCO equipment. The results proved that the dynamic combination of chemistry, platform oscillation, and solution turbulation provided by the RAMCO system, safely and effectively removed all traces of masking wax from internal and exterior surfaces of T 56 engine parts. And the total cycle time was drastically reduced down to 2 minutes in the stripping stage!
The line runs in a left to right L shaped orientation. After stripping, the parts were easily transferred to the next RAMCO stage, via a customized 90-degree “turntable” with drip pan. Washing the parts after stripping was necessary to remove any residual wax removal chemistry. This step of the process was easily accomplished in a heated, platform oscillated, turbulated system, charged with an environmentally friendly aqueous cleaner. The total wash cycle time was also 2 minutes for this stage. To prohibit re-deposition of floating stripper residue onto the parts, the RAMCO SurfaceSweep system was used to clear the surface of the tank, before the platform and parts were elevated.
Finally, to complete the new wax removal process the last stage of the line was devoted to a final heated rinse. Variable stroke oscillation was provided by Multiport Oscillation. The entire process now takes less than half the time of the old technology, uses no hazardous chemistries, and operates in a semi-automated fashion, saving the customer huge amounts of labor.
At the heart of each system is the patented RAMCO NFPA Floating Cylinder used to transport and oscillate the process elevator. The process elevator is the basic building block for each step of the process. It is used to produce changing flow patterns that result in dynamic washing and rinsing modes (i.e. platform oscillation combined with solution turbulation). The effect of “dynamic flow combination” is better coverage of component surfaces, more consistent results and accelerated processing time.
Platform roller conveyors are included (see above) to facilitate transfer between stages. The system is built in accordance with Nema 12 electrical and NEC codes including the control panels, switches, pilot lights and lockout-tagout disconnect switches.
The following photos are of the on site installation –
RAMCO Immersion Washers are built for the rigors of production. The layout (see above) is unique. Nothing is placed underneath processing tanks or tucked behind “access” panels. All valves, pumps, filter housings, pneumatic cylinders, heating elements, etc., are all clearly visible and accessible for inspection and maintenance.