Surprisingly, often on larger machines like gas turbines and diesel engines coupled to generators or compressors, there is less space to mount your brackets than on small machines. The large size of couplings and shafts frequently means that there is very radial clearance in the OD of the coupling hub to provide line of sight, or piping or other structures interfere with rotation, limiting your axial clearances on the shafts as well.

Also, shrouds or other obstacles limiting access to the shafts can cause difficulties in turning them. Yet, there is almost always a way to do an alignment with Pruftechnik tools. Our brackets do not need to be mounted on the shaft, provided the coupling hub is solid to the shaft (ie. rigidly mounted to the shaft.) A variety of magnetic brackets and offset adapters lets you overcome almost any obstacle to rotation or to the line of sight. In fact, anywhere that you can devise a way to mount a dial indicator, you can also mount a bracket to hold a laser component. Here are a few examples:
Here we see the ROTALIGN® SMART EX laser component and Bluetooth module mounted on a solid hub, shooting the beam through the coupling bolt hole. The laser emitter is mounted on the magnetic coupling bolt hole bracket designed for applications like this, and the Bluetooth module is mounted on a compact magnetic bracket, illustrating that the two components need not always necessarily be mounted on the same bracket. This setup allows the laser beam to be shot through an unoccupied bolt hole of the coupling without any hardware protrusion beyond the OD of the coupling.
Here we see the ROTALIGN ULTRA IS sensALIGN laser (on the right) mounted with a compact magnetic bracket to the axially protruding face of the solid hub of the double-engagement gear coupling, in a very limited axial space that would not permit a standard chain bracket to be mounted on the shaft. An offset adapter moves the laser unit forward axially, permitting the setup to overcome the axial obstruction of the machine housing at 3 o’clock.
image3Here we see the ROTALIGN ULTRA laser (on the right) mounted on a magnetic bolt hole bracket to the flywheel of a methane gas engine, overcoming the axial space limitations posed by the shim disk-pack type coupling.
Here we see the ROTALIGN ULTRA receiver mounted on offset support posts on a compact magnetic bracket, overcoming both an axial space limitation preventing the use of the chain brackets and a radial obstruction posed by the pipe seen in the foreground on the left.
Here we see the ROTALIGN SMART EX receiver mounted on a compact magnetic sliding bracket, overcoming both an axial space limitation and a situation in which the shaft cannot be turned by hand. Instead, the magnetic sliding bracket is slid around the solid coupling hub to each measurement position while the laser is rotated past the receiver as the other shaft is rotated using the Pass Mode measurement mode for uncoupled shafts.

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by Alan Luedeking CRL CMRP