QuellTech opted for a combined configuration of two opposed laser line models, mutually displaced in an angle of 180°, with the material to be measured passing between them (works with Q4, Q5 and Q6).
Each of the devices records a height profile of the corresponding surface. The height profiles of the faces are subtracted from each other, resulting in a two-dimensional thickness profile. With a transversal motion of the material (relatively to the profile direction), the result is delivered in form of a two-dimensional illustration of the thickness measurement in 3D.
The QuellTech user software in this complete solution enables individual tolerance ranges to be defined and trends -caused e.g. by worn tools- to be discovered. This means that the software can be parametrized by the user without further programming steps.
Defects to be examined in this application are very small, their size is often lower than 0.5 mm – hard to discover by human eye. Rework in the course of the production of the final product however, proves to be complicated and expensive. Large rolls with a diameter of 2 m and a length of 10 m are very difficult to remove and to reinstall. In order to avoid corresponding inconveniencies, it is essential to support the manufacturing process of the rolls themselves by a reliable quality control in the form of an automated final inspection.As the Quelltech Q6 laser scanner features an extremely precise resolution of 4096 Pixels/Profile at a high scan rate, this model proved to be able to meet the requirements and was mounted onto the positioning stage of the grinding machine. Furthermore, an industrial measurement computer was added, used for the analysis software of the point cloud. On the basis of this configuration, the entire roll surface could be recorded on a helical path.
Wear is a damage consisting in gradual removal or deformation of material on solid surfaces, caused by mechanical (e.g. erosion) or chemical (e.g. corrosion) influences. In machine elements, wear may give rise to material failure or loss of functionality. For the application in question, our client has to measure wear on the surface of rollers in cement mills. Up from a certain depth, reactions are required, generated by a warning system to be developed
In this project, we used several robust QuellTech Q6 scanners to cover fully the roller width. Due to the high rotational speed of the rollers, we preferred our fastest scanners for this application. We furthermore developed a software solution and implemented a warning system, based on the critical depth of the wears on the surface. By means of this system, the customer can determine the correct time for exchange of the rollers.
The seal surfaces in this case are made of very glossy metal, with the drawback of emitted reflections. This effect during an optical measurement must be eliminated. Furthermore, it is absolutely necessary to guide the laser scanner on a linear path over the surface, since fluctuations of distance may falsify the measurement result.
The Quelltech model Q5 disposes of an adequate resolution in X and Z direction and proves to be able to verify the planarity tolerances and to measure the size of defects. Meanwhile a precise rotary axle, used as guiding element, moves the scanner over the surface to be evaluated. Interfering artefacts caused by the glossy finish are suppressed by particular algorithms integrated within the software. As an encoder value is permanently supplied by the rotary axle, the position of each scanner profile within the point cloud can accurately be determined.
In the course of the production, endless cables are running at a considerable speed, and supervision has to be carried out nearly under real-time conditions. The size of the objects to be determined, i.e. of the flaws to be discovered, is in the range of only some hundredths of a mm. Another difficulty is the fact that surfaces with very different reflectivity and roughness are involved. In order to be able to check the cables all around, several laser scanners must be in place, mounted at different angles, thus covering the entire range of 360°.
The solution consists in a configuration of four Q6 laser scanners, mutually displaced by 90°, so the entire surface of the cables is in the field of view.
On the basis of the 100% inline inspection, the position of defects can precisely be determined, without losing too much time.
Q6-Lasor sensor – High Speed, High Resolution – Q6 Sets New Standards for 2D / 3D Measurement:
Resolution of up to 0.6 µm
Profile speed of up to 25.000 profiles/s
Measuring ranges between 2 mm and up to 370 mm available
Laser wave lengths starting from UV via blue, red and green through to IR
The Q6 laser sensor series has already proven its ability in numerous industrial applications demanding a high degree of precision and process stability at increased travel speed.
For common environments, connection is established via GIGE interface and GeniCam. Integration with linear axes and robots is possible by means of encoder inputs and trigger option.
Laser Scanner Solution:
This task is a typical application of the high-resolution QuellTech 2D/3D Q5-880 Blue Laser Scanners. Two of these units are placed at the left and at the right of the measuring objects, at a defined inclination angle. Blue laser light in this case is a prerequisite, as the cast parts are red-hot, hence emitting in the red spectral range. Additionally, the client was in need of a software solution for the project, so a 3D point cloud processing application was implemented, performing inline and evaluating width, height and angle results.
QuellTech customer is able to inspect continuously the product quality, simultaneously avoiding scrap. He uses the same system for more than 10 different types of castings. Errors caused by manual inspection are considerably reduced, and safety for personnel is enhanced.
Within the frame of quality assurance, the forged pieces of this client have to be checked in an inline inspection with respect to several parameters: Inner and outer diameters, as well as the absence of surface defects have to be verified.
Video of inline forgings inspection for dimensional accuracy and surface defects with QuellTech LaserScaner.
Manual inspection carried out until now turned out to be not reliable enough, particularly after an increase in production. The final rejection rate has seriously affected the productivity of the entire manufacturing process. A solution for a contactless inline inspection was needed.
The QuellTech Solution
A testing station including an index table has been designed. This configuration acts as a support for two QuellTech Q4-60 laser scanners, used for inspection of the parameters mentioned above.
The new QuellTech Q5 Laser Scanner Series combines the advantages of small form factors with both high resolution and scan rate.
The sensor disposes of different set-up possibilities with respect to the analysis algorithm. Measurement results are delivered via Ethernet, calibrated in the X / Z plane.
Special adjustable algorithms can be selected, extremely useful particularly also for optically most demanding surfaces. Time-consuming calibration tasks for the user are no more required, as the calibration routine runs on board.
High Scan Rate with up to 14,000 Profiles per Second
Due to an appropriate limitation of the image range (AOI) in X and Z direction, the scan rate could considerably be increased.
High resolution and detection frequency with up to 14.000 profiles and 28 Mio. points per second
•X measuring range from 10 to 1022 mm
•Z measuring range (height) from 5 to 878 mm
•Laser wave length blue 405/450nm, red 650nm
Laser sensor Q4 – with a small form factor – Q4 for standard 2D / 3D measuring applications:
Low sensitivity against influences of secondary light
Measuring ranges from 5 mm to 1000 mm
Laser wave lengths starting from UV via blue, red and green through to IR
Average measuring speed up to 350 Hz frame
The Q4 laser sensor has been designed to meet the requirements of standard measuring applications. Thanks to its increased flexibility, it can be used for several tasks also in complex projects. The dimensions of the ultra-compact version amount to only 86x40x25, at a weight of 140 g. Protective panes and cooling modules are available as an option.
The Q4 laser sensor model enables users to obtain stable measuring results also on difficult surfaces, whether mirroring or transparent. The QS-View Standard Software comprises a comprehensive selection of application modules, to be invoked at once without previous programming steps. Customized adaptations are possible any time.