A software-driven comparative gauge from Renishaw is being employed by aero-engine component maker Meyer Tool of Cincinnati, OH to soften up the cost of numerous hard gauges at their facility.
Meyer Tool is a quality driven US-based producer of hot-section jet engine components for aerospace OEMs. The company designs, builds and maintains dozens of these costly gauges every year for in-process measurement.
Commenting on the impact on its inventory of custom hard gauges, Beau Easton, Quality Manager at the company says that a single Renishaw Equator software-driven gauge has eliminated at least four costly hard gauges in a new work cell.
Each custom hard gauge costs Meyer Tool several thousands of dollars to design, build and maintain in addition to design changes down the line that could add a few more thousands in cost to re-configure and qualify an existing gauge.
Meyer Tool primarily relies on work-cell-based point-to-point contact gauges, using pneumatic digital probes for in-process dimensional measurement. Hard gauges in the machining cell give very fast feedback but are expensive.
When shown Renishaw's Equator comparative gauges and offered a pre-launch trial, Easton and SPC Manager Bridget Nolan immediately recognised the potential.
Nolan explains that Renishaw programmed the parts provided to them, and the results matched Meyer Tool’s Coordinate Measuring Machine (CMM) results.
The Equator gauging system uses the comparison method of mastering and measuring wherein a master component with features of known dimensions is used to ‘zero’ the system, with all subsequent measurements compared to this part.
The Equator system uses a highly repeatable and radically different metrology mechanism based on a parallel kinematic structure, and which is lightweight, allowing rapid motion, yet very stiff and repeatable.
The system uses Renishaw touch and scanning probes, styli and stylus change racks, and MODUS Equator programming software. The software-driven Renishaw comparative gauges can each replace, cost-wise three to five hard gauges in a Meyer Tool work cell. Additionally, the Equator can be used for multiple parts, switching between them in seconds, as well as reprogrammed for many other parts over its life.
The Equator gauging system is currently assigned to a lean machining cell in Meyer Tool's shop. Demonstrating its adaptability, it integrates with Meyer's Orion SPC system, maintaining a familiar look for machinists and shortening the learning curve.
Orion communicates with the Equator's MODUS software, presenting the results in the form of dimensional data and SPC charts among others, allowing the operator to determine CNC.
The parts must meet tolerances of ±0.001 to ±0.003 inches. Inspection time varies with the part but typically takes two to six minutes, well within the TAKT time of the cell so the system easily keeps pace with machining operations.
Nolan’s team is already gauging five part numbers for two different engine programs, enabling them to set up and qualify multiple fixturing tiles for the Equator. In addition to combining as many different operations on one tile as possible to limit their qualifications, they are also currently working on one tile that will combine three.
The team is also working on GD&T true positions, notches, hole diameters, profiles and runout with touch probing, though they are implementing contact scanning with the SP25M probe. Since they use at least four different styli, it's very convenient not to have to re-qualify with every change, says Nolan.
The Equator measurements at Meyer Tool are correlated with those from a CMM, using a CMM-calibrated master part. Nolan explains that the master part sets the values the Equator expects to find inside its measuring envelope while the software automatically applies the compensation values from nominal taken by the CMM.
There is no need to re-master on every part change since Meyer has decided to re-master on a 3-hour schedule to compensate for changes in the plant's temperature. Nolan adds that the Equator system memorises the master parts and validation scores, allowing them to switch parts as many times as needed during the 3-hour window without having to re-master.
Using well over 100 very expensive hard gauges throughout its facilities, Meyer Tool recognises the potential cost advantages of Renishaw’s flexible, software-driven gauging systems.
Renishaw Oceania represents the Renishaw group in Australia and New Zealand.