| abstract |
Alignment apparatus and method for aligning a pair of machines having first and second rotating shafts in a machine train with at least one flexible coupling interconnecting the first and second shafts. The flexible coupling has at least one member connected to one of the shafts and is capable of accommodating at least some misalignment of the first and second shafts. One of the first and second shafts is considered as a reference shaft and the other of said first and second shafts is considered as a movable shaft. Means is carried by the shafts having surfaces spaced apart circumferentially with respect to the axis of rotation of the shafts which represent the orientation of one of said shafts and serve as reference surfaces. Paddle means is carried by the flexible coupling and has surfaces spaced apart circumferentially with respect to the axis of rotation of the shafts and representing the orientation of the one member of the flexible coupling. Probe means is provided for sensing the position of the reference surfaces and the last named surfaces to provide information on the gap or spacing between the probe means and the surfaces. The information supplied by the probe is utilized for giving an indication of the axial motion of the machines, both steady state and dynamically and both relatively and absolutely. In addition, the apparatus provides net coupling hub motion of each machine due to any dynamic motion of each rotor, such as that due to fixed bows, thermal bows, unbalance bows and other action at rotative speed in a forward direction and also that due to any other action at other than rotative speed in a forward direction such as oil whirl, reexcitation of balance resonances and other actions that create shaft motions. |