Accurate placement and precise shaft alignment of machinery components is key for optimal and efficient operation. Although none of the traditional methods are bad or inadequate if carried out correctly, they can be complex and time consuming the least.
Especially with large machinery, many situations exist where shaft rotation is impractical or not possible at all. For one example case we were requested to determine the “As found” alignment of a multiple component machine train, where rotation of the shaft was not possible. The alignment and position of each component in the machine train was measured and determined with respect to an external reference points via global 3D coordinates and within tolerances of ±0,05 mm. By taking measurements on many positions this accuracy can even be further increased to determine flange positions and angle within typical machine alignment tolerances.
After exchanging the e-motor (> 70 ton, 25.4 MW) in-between other train components we were able to reposition the new e-motor exactly in the same position as the original “As found” position. Besides the speed and accuracy of this method, another significant advantage is the global overview over the alignment of the complete machine train that is created together with detailed coupling to coupling in all directions and rotations. This cannot be achieved with any of the traditional methods.
In addition, since the measurements are based on 3D coordinates many other geometrical parameters such as flatness and levelness can be checked and correlated with the alignment information. This method has proven to be very powerful large part inspections and with the placement and installation of internal machinery components such as disc carriers or impellor houses.
Also, when alignment specifications are not available and/or considered to be incorrect our advanced, high precision 3D Laser measurement can be used to determine the (differential) thermal growth between machinery components such as Gas Turbines and its driven equipment. Automated displacement measurements can be performed over the course of an hour or up to several of days continuous monitoring. We have multiple reference cases in which the start-up of a gas turbine driven compressor systems have been measured to determine the actual thermal growth and to re-engineer the ideal cold alignment offset specifications with a precision of ~100µm. Correlating measurement data from the 3D measurements and the continuous thermographic monitoring enables very detailed analysis. Additionally, a load/deformation study on the casing/piping can be performed with displacements measurements during various load configurations.
About the Author
Geert van RijswickGeneral Manager, van Geffen AMS BV
Geert is Principal Engineer and General Manager at van Geffen Allround Machine Support and is specialized in machinery diagnostics, advanced vibration analysis and machinery alignment. Motivated by a strong and lifelong interest in technology he received his engineering degree in 2004 and worked as a noise & vibration engineering at BMW’s Innovation Centre in Munich before joining van Geffen Allround Machine Support in 2007. He has gained extensive experience in the field of rotor & structural dynamics, machinery diagnostic including vibration/pulsation analysis during engineering and management roles in the past 15 years, from NVH to Machinery Diagnostics. In his current roll as General Manager and Principal engineer he leads a team of highly skilled diagnostic engineers and consultants and is still actively involved as a vibration and diagnostics specialist in many projects. He also guides R&D projects with the pursuit to combine practical problem solving with advanced, high level analytical skills and technology capabilities.