Abstract: The present invention concerns a measurement method of the alignment status of a shaft line (16) in rotating machineries and an apparatus for the implementation of the method. According to the invention, the displacement of alignment is measured at convenient points of the shaft line (16) from the displacement of an optically fanned laser beam (4) hitting sensor units (10, 11). At the beginning of a measurement session, a zero reference point is determined for the beam (4) and the measurement values of the sensor units (10, 11) are compared against this reference value during the measurement session. The relative displacement is obtained as the difference between the initial value and the value during the measurement. The apparatus and method is also applicable to the measurement of displacements in pipelines, long shafts and other similar systems.

Abstract: The present invention concerns a measurement method of the alignment status of a shaft line (16) in rotating machineries and an apparatus for the implementation of the method. According to the invention, the displacement of alignment is measured at convenient points of the shaft line (16) from the displacement of an optically fanned laser beam (4) hitting sensor units (10, 11). At the beginning of a measurement session, a zero reference point is determined for the beam (4) and the measurement values of the sensor units (10, 11) are compared against this reference value during the measurement session. The relative displacement is obtained as the difference between the initial value and the value during the measurement. The apparatus and method is also applicable to the measurement of displacements in pipelines, long shafts and other similar systems.