3D scanning a steam turbine in Mexico in steaming hot weather!

Last February, I was lucky enough to escape Quebec City’s harsh winter season for a while and fly to the warm Altamira region of Mexico in order to complete a 3D scanning project.

Turbocare asked Creaform to take several 3D measurements in a thermoelectric plant using steam turbines. The goal of this project was to replace the old, worn units, but also to improve the energy efficiency of the plant.

Given the extended scope of the project, it was impossible to replace everything in this dated plant, and it was decided that the envelopes on which the diaphragms were sitting had to stay in place. My task was to scan the diaphragms, their envelope and the rotor to get reliable measurements on which to reverse engineer the replacement parts. Doing so would ensure that everything properly fit in its right place during installation.

Since Turbocare needed to digitize each side of the diaphragm, we had to use devices that would provide very a accurate positioning model that would make it possible to link both sides of the object. So, I geared myself with the Handyscan 3D self-positioning portable 3D scanner and the MaxSHOT optical coordinate measuring system.

Dealing with unwanted vibrations

I also realized that I was bound to deal with vibrations – I was working in a thermoelectric plant! Luckily, I quickly solved this problem by placing referencing targets on the objects to be scanned to take advantage of Creaform’s TRUaccuracy dynamic referencing feature, which make the system (and the generated results) completely insensitive to vibrations. Consequently, there was no loss of accuracy during scanning, even if the diaphragms were placed in a somewhat unstable vertical position.

Working with a portable scanner really helped me moving easily to directly reach the object to be scanned instead of having to wait for technicians to place it for me. This made the scanning a lot quicker, especially for the diaphragms. Some parts like the turbine stands were a little harder to reach and offered very little space to work, but all in all, everything went smoothly.

Working in sunny Mexico, or how to make sure that high temperatures have no effect on data

The temperature in Mexico was very nice at sunrise… but it quickly became suffocating in the early morning. Since this heat was having an impact on my body (and my sweating!), I figured it might be impacting the internal components of the scanner and coordinate system as well. Better safe than sorry, I made sure to calibrate the device 3 times a day to reflect temperature changes and guarantee data repeatability and accuracy. As the calibration process of a Handyscan 3D is so quick and easy (less than 1 minute), this really was a piece of cake.

When power generation engineers are happy, everybody is!

Turbocare engineers really appreciated working in parallel with Creaform technologies, because they saved time (quick data acquisition process) and were able to ensure high accuracy, which is an important benefit when performing reverse engineering.

Because our 3D measurement solutions deliver quality scanning data and versatility, Turbocare has become a returning client and often requests our metrology services for various projects throughout the world. I personally had the chance to work with them twice since, once more in Mexico and in the USA.