Aircraft engine manufacturer uses non-standard sump sizes which makes it difficult to change out coolant from the sumps and reduce odors and bacteria.
Tramp Oil Separators, Automatic Air Sparger
Pratt & Whitney has multiple vertical turret lathes, vertical machining centers, and horizontal machining centers in their aircraft engine manufacturing facility. The biggest challenge that Pratt & Whitney faced with these machines was the non-standard sump sizes. Some were only 3 to 4 inches in depth and very narrow, while others were much deeper and narrow. PRAB’s engineers evaluated and tested all types of skimmers before finalizing a design for a Hammerhead skimmer. This oil skimmer, which is shaped like a “T”, is able to lay flat in a shallow sump and skim tramp oil and coolant down to 1.5 inches in depth in a coolant sump. If the coolant level rises, the Hammerhead skimmer pivots upward with the increased coolant level. Also because of the compact size, the Hammerhead skimmer will work in the deep, narrow confines of the sumps on the Giddings & Lewis vertical turret lathes.
Pratt & Whitney were unable to develop a convenient maintenance program to change out coolant from the machine sumps on a regular basis. This was due to the configuration of machine sumps, operations of individual machines, and a limited number of maintenance personnel. Therefore, the decision was made to install individual tramp oil separators on each machine to keep the coolant clean on a continuous basis. The installation of thetramp oil separators eliminated the need to change out coolants from the sumps and reduced odors and bacteria.
PRAB also developed a method to clean the media on a daily basis with an automatic air sparger. The separator’s controller will shut the separator pump off and then turn the air sparger on to clean the media. After the sparger runs for two minutes, it will shut down and the separator will turn back on. This allows the Tramp Oil Separator to operate maintenance free for extended periods of time.
Pratt & Whitney replaced several Phasep separators with the PRAB units. This was due to their poor skimmer design, the poor reliability of their air diaphragm pump, and the high maintenance required by their plate pack media.