WM Quartis- How to measure quick and easy
This is part 2 of Quartis to learn about the strengths of this software solution when it comes to measuring blades. Last week we learned about the basic features of Quartis and this week we want to transfer this knowledge to measure turbine blades. Actually, a lot of blade features can be measured with standard measuring features and for those that aren’t, WENZEL developed fully automated solutions like measuring, evaluating and reporting strategies to make working with Quartis easy and intuitive. Everything will be adapted to measuring with the CORE D, since this 5-axis CMM is especially designed for measuring turbine blades. We will focus on the WM HS hybrid sensor system that can switch between high-speed optical and high-precision tactile measuring.
Time for a closer look at WM Quartis
Let’s see how easy is to use Quartis to measure, evaluate and report starting with the GUI of Quartis. We use the Microsoft user interface (Microsoft Fluent interface) following its guides and rules, menus, toolbars, bars, buttons etc. In the top you can find all the tool bars that you need for the Quartis functions, machine setup, measuring, and evaluating of those measured features. These tool bars are fixed and always shown.
In the middle of the screen you can find your workplace with different windows to activate. These can be the graphics window, a database table, the program code, the reports section etc.. All these workplaces have separate tool bars that show up on top whenever you work within these workplaces. On the left there is a elements window that show you the details of whichever element you clicked on. On the right you can find the status of your machine, workpiece, measurement, probe, axis system, temperatures etc.
Starting with your physical workpiece - The blade.
Every blade is different but all of them share a significant detail. They are built and machined in reference to the longitudinal blade axis. This means that we are trying to use this feature, take our turbine blade and clamp it right in the middle of the rotary axis of the CORE D. Sometimes you can stick to standard centric clamping vices, sometimes, when it comes to special root profiles (e.g. fire-tree), you need to add blade-specific clamping jaws and sometimes additional engineering for more complex root shapes needs to be done. All these methods have in common that the blade axis and the rotary axis are parallel, so we can turn the rotary table while measuring and reach each geometrical element with ease.
Clamping can be done manually, automated (pressured air) or even fully automated with robots that load your CORE D.
How do you set up your blade measurement?
After clamping the blade you can open Quartis and start working in the tool bars from left to right. Using the Quartis bar (create, open, save, import, export, settings) you load your CAD-model of the blade. The axis system of the CAD model (usually its the middle of the turbine) gets arranged on top of the machine axis system. The physical placement of the blade inside the CORE D and the arrangement inside Quartis usually differ since the blade gets arranged via the global CAD-turbine axis system. You can fit your blade easily with some of the internal fitting options that Quartis offers. You can load additional CAD models like mentioned special clamping devices. This is necessary for collision control during the measurements.
You can switch over to the next tool bar.
The Machine bar can be used to set up your measurement conditions like speeds, search distances etc.. In addition you can calibrate your probe system and your rotary axis of the CORE D. These are automated procedures that need no further action other than just clicking “start calibration”. You should do this regularly to avoid any incorrect measurements.
How do you measure a blade?
In the Measuring bar we see all the functionalities we need to measure elements, construct elements and align the workpiece - our blade. A first vague alignment can be done by manually probing easy recognizable surfaces and points. Usually, you should use areas that are used for the blade assembly (especially root surfaces) to increase positioning accuracy. Now your physical placement of the blade inside the CORE D and the arrangement inside Quartis are quite on point. Everything is setup to start the fully automated precise alignment and measuring. By fully automated we are talking about no more manual probing of the workpiece.
From now on you just work within Quartis, plan your next steps and everything will be performed in real-time by the CORE D.
For the precise alignment you need to take the assembly geometries (usually root geometries) and the according drawing into consideration to find the “right way” to align your blade. Usually, its a good decision to track the blade axis and align your workpiece along this axis. You can do that by measuring the root profiles on each side, and creating a symmetric plane “A” in-between. For the root-profile-limiting surfaces it depends on the assembly method.
If the blade is assembled in a symmetric way you can repeat this process, if it is assembled via a side contact you should find a value on your drawing that shows the distance of your axis to that side surface. In both cases you get a second plane “B” in the middle of the blade. Now you can intersect plane “A” and “B” with a Quartis design function and you get your blade axis right in the middle of the blade.
In combination with two other points to lock the rotation around this axis and a third point to lock the blade in height you got all your elements to precisely align the blade within Quartis and perfectly match the physical blade on the CORE D. Different alignment functions are available to achieve this desired final state.
After aligning your blade, you can start the automated measuring. You simple choose your element (plane, point, circle, cylinder, curve, etc.) in the measuring bar, click onto the CAD model, check your measurement settings, confirm and the measurement (e.g. measuring strategy, filters, additional safety paths, etc.) will be performed in real time virtually inside Quartis and physically by the machine. None of these functions are blade specific since Quartis offers all the measurement functionalities that you need for your blade measurement, starting from points and planes to complex curves.
Especially the measurement of the airfoil can’t be easier. You take a look at your drawing that shows you the height of airfoil profiles to measure. You simply design these profiles by intersecting the airfoil surface with an intersection plane and as a result you get your profile. Then you can simply click on curve measurement, choose the profile and the CORE D starts measuring.
The CORE D starts measuring the profile and for that case the blade needs to turn around its blade axis a lot. The required rotational movements of the CORE D will be performed automatically to align the sensor in the best possible way to achieve the best measuring performance. This is where the power of 5-axis simultaneous measurement shines. For the best efficiency you can use the high-speed scanning mode of the optical sensor. Don’t miss our video in the next post, next week.
Advanced settings for blade recognition, sensor performance and 5-axis settings can be adjusted if needed. All these features will be discussed in a future blog post.
How do you evaluate your blade measurements?
In the next tool bar, the Features bar, we find all the features we can evaluate. You simply chose a feature (straightness, symmetry, position, profile tolerance etc.), choose your measured element and the evaluation is done. Advanced settings depending on how you want to evaluate specific features are available too.
For blade profiles you get the possibility to evaluate them with the BladeAnalyzer. Here the main features of a turbine blade profile (leading and trailing edge radius, profile tolerance, required profile fitting as feedback for the manufacturing process, etc.) are evaluated automatically and written into a report. More about this special software solution in one of the next posts.
How do you organize all your data in a blade report?
To switch to the Report bar, you have to switch form the graphical workplace to the report workplace. The corresponding tool bar will show up. By creating a new report, you can choose to use an empty page or a self-made template depending on what is relevant for your company. Now you simply choose a picture for your blade, the elements that you want to include within your report and everything will be aligned within the report automatically. You can save the report as Quartis reports, pdf, text or csv-file.
How do I automate this?
All these things can be tracked by the program manager that automatically saves each step of your work and saves it as a “step list”. The next time you want to measure the same part you simply load your program, press start and every step will be done in the same way. No manual programming or code-writing is needed.
With WM Quartis you can generate meaningful results quick and easy!!
Stay tune and learn how easy it is to work with Quartis and CORE D and evaluate blades with WM Blade Analyzer in the following weeks #allaboutblades
Author: Michael Kopper
Transcribed by Sarit Cepeda