Shaft Alignment

Correct shaft alignment is a key issue on ships, especially on large vessels such as containerships, bulks, tankers, and gas-carriers. Any wrong alignment of the shaft may result in undesirable vibrations and higher operating costs. Furthermore, damage to the stern tube bearings or other key parts of the vessel’s propulsion equipment could result in the ship being immobilised.

Consequently, shaft alignment stage during new building or repair requires a specific procedure with accurate measurements. Tecnitas provides in situ laser measurement service to ship owners and ship yards.

Regarding marine applications, laser sightings performed in dry dock enable to measure the relative offsets of stern tube and intermediate bearings. In addition, GAP & SAG measurements at flanges could also be carried out in order to tune the position of each intermediate bearing according to calculated values.

Tecnitas main strength is to provide global service offer including in situ measurements, elastic alignment calculation performed by Tecnitas with LILAS software and support/supervision during (re)mounting.

Our solutions may also be suitable for any onshore/offshore facility, particularly for shaft alignment of rotating machines such as turbines, pumps, motor, etc., in a general context of new building or repair after damage.

Tecnitas complete set of services to Clients consists in:

  • Measurement of bore alignment
  • Alignment of stern tube bearing with several measurement points in each bearings
  • GAP/SAG measurements
  • Supervision of remounting
  • Elastic Shaft Alignment calculation


  • Laser measurement
  • Reach of 200m
  • Horizontal and vertical offsets 

The alignment of bearing journals in relation to the stern tube (or gearbox) is carried out using linebore equipment, where the laser transmitter is mounted on the axial surface at one end of the stern tube (or the gearbox flange) and the detector unit is placed in the bearing position. Measurement values are recorded in two positions for each bearing position (the detector unit is rotated through 180°), the measurement program calculates and then displays the position in the vertical and horizontal directions.