TABLE OF CONTENTS A run out test of either or both couplings holds the status of importance only if there s a run out problem. Sort of like seat belts you may need them only once, but which once?
Seldom will the run out of a pump or motor coupling be enough to detect with the eye alone. Standard practice is to position a Rim and Face indicator setup to the uncoupled couplings (one at the time) and roll said couplings through several full turns while monitoring the indicators. While this is being done, the indicator bracket should be attached to a static object close to the pump or motor coupling being checked. Usually a magnetic base designed to hold indicators is the device used for this purpose if there is more than 5 or 6 inches between the involved couplings. For an ordinary pump and motor, however, it s usually more convenient to mount the indicator jig on the motor coupling for the run out test on the pump coupling, then vice-versa to check the motor coupling.
Shown in FIGURE (1) is a profile and a bull s eye view of a typical run out check setup involving the use of indicators attached to a magnetic base. Assume the Rim indicator to have been adjusted to zero and the coupling being checked is rotated several full turns. Repeated turns delivered repeated readings of a maximum minus of 0.xxx inch at one extreme and a maximum plus of 0.xxx inch at the...
