Bore hole inspection

Measuring System: BoreInspect
Keywords: bores, cylinders, valves, bore ID, aerospace, automotive, precision machining, diameter, cross-holes, cavities

Internal surfaces of bore holes in many high-precision sectors need to adhere to strict specifications in terms of:

  • dimensions (GD&T)
  • diameter, straightness, cylindricity, conicity, ovality, taper, distortion, runout
  • inner features such as steps, threads, cavities, chambers, cross-holes, grooves, and o-rings
  • absence or low incidence of defects
  • roughness characteristics.

Novacam BoreInspect greatly speeds up the task of high-precision bore inspection and facilitates automation. This modular non-contact inspection system features a rotational scanner with a small-diameter probe that easily enters bores to acquire their inner 3D topography directly and down to the micron.

The optical probe of the BoreInspect scans a bore ID as it rotates and moves into the bore.

The optical probe of the BoreInspect scans a bore ID as it rotates and moves into the bore.

Multiple bores can be measured and analyzed for defects in one inspection sequence. Here, a deviation map of 4 valve body cylinders acquired in one automated scanning sequence highlights out-of-spec measurements.

Multiple bores can be measured and analyzed for defects in one inspection sequence. Here, a deviation map of 4 valve body cylinders acquired in one automated scanning sequence highlights out-of-spec measurements – click for closeup

Automated or in-lab inspection

Surface acquisition and the subsequent 2D/3D characterization (which is dimensional), roughness measurement, and defect detection are easily automated and carried out right on the shop or manufacturing plant floor, bringing high-precision manufacturers significant savings. Automation is supported by system capabilities such as datum alignment, automated pass/fail reporting, and exportable reports. Bore ID data may be evaluated with respect to user-defined criteria (GD&T, inner feature specifications, roughness, and defect inspection), or compared to a reference CAD model. For in-lab inspection, accompanying metrology software on a PC (e.g., PolyWorksTM) enables full viewing and analysis of the acquired point cloud as a 3D interactive map. Views such as deviation maps provide key insight into bore machining processes.

Flexible installation

The BoreInspect system is based on low-coherence interferometry technology. It is a modular and fiber-based optical system; its scanner is connected to the signal-processing profilometer with an optical fiber that can be hundreds of meters long. As such, the scanner is easily integrated as either a robot arm end-effector or as a 3D vision component in automated or semi-automated systems on the plant floor.