General Procedure
Permanently attach benchmarks to the equipment and to the foundation at or near each bearing location.  Where bearing housings are readily-accessible, benchmarks are typically placed as shown in Figure 1.  Where bearing housings are not readily-accessible, benchmarks may be placed as shown in Figure 2.  In either case, all benchmarks at a given bearing location lie in a plane normal to the shaft centerline.  Recommendations for placement of benchmarks are furnished with benchmark gauge sets.  After installing the benchmarks, align the equipment in the normal manner and record final alignment readings.  Using the benchmark gauge, measure and record the distance between each pair of benchmarks (A and B in Fig. 1, or A, B, C and D in Fig. 2). Also measure and record the angles at which the readings are taken.  Angles are measured using the inclinometer furnished with the benchmark gauge set.

        When the equipment is brought on line and reaches normal operating temperature, again take and record benchmark gauge readings at each location.  Any movement of the machines from the initial (cold) to the final (hot) condition will be reflected in changes of benchmark gauge readings.  By using PC programs furnished with each benchmark gauge set, the following information can be obtained without stopping the equipment for a "hot check":

* Vertical and horizontal movements at each benchmark location (Fig. 3 or 4).

* Alignment of the machines in the running condition (Fig. 5 or 6).

* Shim changes and horizontal movements required to improve alignment, if desired.