LK Metrology Introduces Plug-and-Play Probe for Surface Roughness Measurement

Source | LK Metrology

Coordinate measuring machine (CMM) manufacturer LK Metrology (Derbyshire, U.K.) introduces the Surfacer SRP. It is a plug-and-play probe with a 1-µm resolution, which enables seamless analyzing of component or part surface roughness as part of a CNC measuring cycle on any CMM, provided it has an industry-standard probe head.

The sensor eliminates the need for secondary surface roughness inspection, either manually using a handheld instrument, or automatically at a separate metrology station. Manufacturers are able to conduct comprehensive inspection on a component in a single setup in a CMM environment, resulting in time and cost savings. Engineered for ease of use and versatility, the equipment comes with its own downloadable application software, facilitating integration and eliminating the need for third-party software.

Easy swapping between touch probes, tactile scanning probes, noncontact laser scanners and the roughness probe gives users extended multi-sensor capability, LK Metrology reports. The Surfacer SRP mounting is compatible with change racks, including the new versions introduced recently by LK, enabling automated sensor changing and enhanced operational efficiency.

At the heart of the roughness probe lies a body that accommodates three interchangeable, skidded, stainless-steel probe modules. One evaluates flat, conical and cylindrical surfaces; another measures concave, convex and spherical surfaces; and a third is for inspecting grooves more than 3 mm wide and less than 10 mm deep, or steps of similar height.

The CMM positions a stylus so that it is in contact with the part, after which the machine axes remain stationary while the probe moves the stylus across the surface under investigation. Wireless communication with the CMM computer via a Bluetooth 4.0 adapter provides seamless data transfer for analysis, simplifying installation.

The skid plays a key role during measurement, acting as a straight-line datum that guides the stylus across a surface to ensure probe stability. The stylus travels independently of, and slightly in front of, the skid, with surface deviations recorded as the difference in the relative movements of the two elements in the Z-axis. The design ensures that even minute surface irregularities are captured with high accuracy.

Further enhancing the precision of the Surfacer SRP is an integrated preload mechanism, which during stylus operation isolates it from the CMM kinematics, ensuring accurate and consistent results regardless of external vibration or machine movement. The force exerted by the stylus tip, which has a radius of 5 µm, is less than four thousandths of a newton, avoiding surface deformation. Measurable roughness range is 0.5-6.5 Ra, which is the average roughness between the profile and the mean line.