The HandyTube laser microscope image depicts height variation and measures high/low point averages. Blue areas are low, green mid-range and red high.

Gauging tube surfaces to achieve a desired smoothness can be a painstaking and time-consuming process. Many tubing suppliers use profilometers to measure surfaces, but this technique involves a long setup time, and it is not without limitations and accuracy concerns. That’s why HandyTube now applies laser confocal microscope technology. Not only does it provide fast results, it creates a more in-depth profile, with more accuracy and less variation than a profilometer.

A traditional profilometer gets a reading via a stylus which contacts and moves along the tube’s surface. Unlike a profilometer, a laser conformal microscope does not touch the surface at all. HandyTube employs an Olympus LEXT OLS5000 laser confocal microscope with 4k scanning technology that can quickly detect near-perpendicular surface features and very low slopes. This allows a user to view the surface at various depths, giving a more accurate picture of the tube’s surface roughness. The laser microscope also lets HandyTube check larger surface areas to achieve a more accurate roughness average (Ra) than profilometers which can only measure the inner diameter surface in a straight line.

Steel tubes with smooth inner diameters provide customers with better transport than those with a rougher surface which can otherwise cause materials to stick to the tube and hinder flow. The Olympus LEXT OLS5000 is able to scan tube inner diameters as small as 0.010 inches. Because it can measure smaller inner diameter surfaces than possible with other gauging methods, HandyTube can change processes as needed. The technology can also automatically detect conditions that cause measurement variations — such as the edge position and the threshold of the reference planes in volume analysis — so they can be corrected to ensure stable results.

While the laser microscope is used primarily to check inner diameter surface roughness after each draw application, HandyTube also can measure the outer diameter as well as calculate:

  • the distance between centers.
  • wall thickness.
  • concentricity.

Check Your Supplier’s Surface Measurement Process

Metal tubing buyers need to be certain their inner diameter surfaces are as smooth as possible. While many tubing suppliers test surface finish for smoothness, not all surface measurement methods are the same. Be sure to look for a supplier with the technology to accurately check inner diameter surfaces less than 0.050 inches. HandyTube employs a laser confocal microscope with 4k scanning technology to deliver faster, more accurate results than the traditional profilometer, so customers can obtain tubes quicker as well as achieve greater material transport and productivity for their installation.