Custom Air Bearing Radial Thickness Gage for Measuring Engine Bearings
A major US engine manufacturer had a unique metrology requirement: in order to determine wear patterns and evaluate new materials and coatings, they needed a gage that could measure thickness variation on engine bearing halves before and after Dyno testing. The gage needed to have an accuracy of 0.25 microns or better, and a resolution of .025 microns.
ABTech was selected to develop a custom thickness gage. To meet the customer’s needs, the MicroForm µFG150 gage platform – with its integrated rotary air bearing table – was chosen as the foundation for the custom gage.
To keep costs down, our engineers leveraged existing component designs where ever possible. Modifications were made to the adjustable tilt and center worktable assembly and vertical height adjustments. Nonetheless, some completely new designs were needed to create a quick part holding device; air actuation and controller for the probes; and a manual rotational drive mechanism.
One of the project’s major challenges was to provide the specified accuracy over a large thickness range. This required the development of miniature encoded linear air bearing stages to perform as the sensor. Two of these stages were used to trace the inner and outer surfaces of the bearings, creating a map of the part’s thickness. And as defined by the operator in the gage software, multiple traces made at different heights of the bearing are then overlaid and analyzed relative to each bearing’s unique tolerance window.
The project from final scope definition to gage delivery was completed in less than ten months.
Installation and training at the manufacturer’s research and development facility was performed in one day with actual parts off the Dyno being tested the same day.