Applying Inductive Technology to Detect Grinding Burn

This sensor-based technology for gear measuring machines quickly detects grinding burn and other imperfections on the surface of ground gears and related components.


Facebook Share Icon LinkedIn Share Icon Twitter Share Icon Share by EMail icon Print Icon

Caustic, secondary acid-etching processes are commonly used to determine the presence of harmful grinding burn, which involves changes in both the surface stress and microstructure of ground ferromagnetic workpieces. Now, shops have another option. Germany-based Wenzel (with U.S. headquarters located in Wixom, Michigan) offers a safer, sensor-based technology for use with its gear measuring machines that quickly detects grinding burn and other imperfections on the surface of ground gears and related components.

Developed in conjunction with Stresstech GmbH, a German producer of non-destructive process control equipment, Wenzel’s sensing technology uses magnetic Barkhausen Noise Analysis (BNA) to detect defects on a gear’s ground surfaces. Simply put, BNA examines the microstructure of a material’s surface through inductive measurement of a noise-like signal generated when a magnetic field is applied to a ferrous object. BNA is particularly effective for such inspection applications because grinding modifies both a material’s surface stress and microstructure.

Chris Pomm, technical director for Wenzel, says because gear measuring machines use sophisticated programming software to inspect all geometric features of a gear, it’s logical that a sensor adapted for use on those machines could be used to identify grinding burn and pitting that can occur on the flanks of gear teeth. The company’s new BNA method saves time by enabling users to analyze potential grinding burn on flanks at the same time workpiece measurement occurs. This eliminates the need for an additional inspection process.

The digital BNA system Wenzel offers on its GearTec InovaGear, WGT and LH measuring machines is Stresstech’s Rollscan R300. This system includes the BNA analyzing unit and sensor as well as software that integrates into the host measuring machine’s controller. The BNA sensor is incorporated into a Renishaw SP80 probe that can be conveniently stored in a probe change rack. According to the company, inspection routines with the Rollscan are fast enough to match the production rates of most manufacturing lines, enabling accurate process control in real-time. This offers shops the potential to realize significant quality improvements in addition to reduced material and labor costs.


  • Do's And Don'ts For Keeping Dial Indicators In The Game

    Just because dial indicators have been around since the early 1900s, don't expect them to fade away with the last century. This tool's long-term popularity is well earned.

  • DFGT - Double Flank Gear Testing

    Functional gear testing, also known as total radial composite deviation, is a method of looking at the total effect of gear errors. This test method simulates the conditions under which a set of gears is likely to operate as a result of the gears meshing together.

  • Working With Your Working Gage Blocks

    The uses of working gage blocks are as varied as the number of gage blocks in a large set. The working blocks have an intermediate grade and are often used in the inspection or calibration lab, but they may also be found on the shop floor.