Cleveland Motion Controls ULTRA ISC CARTRIDGE TRANSDUCER REV AA - Manual (Page 29)

MAN-70430-0 R EV AA U LTRA S ERIES S TATIONARY S HAFT T RANSDUCER T ECHNICAL M ANUAL
4.5 Mounting the Sensing Roll
The following steps take into consideration the risk and difficulty of handling large rolls and help to
minimize the number of failed attempts at mounting the roll.
1. Before mounting the sensing roll, confirm that the transducer bodies are securely mounted and that
they are “in line” with each other (coaxial).
2. Measure the roll shaft diameter, the shaft coupling bore diameter and any bushings (if used) to be
sure that they fit properly.
3. If you are using bushings, be sure that they are split on their circumference so that they readily
yield to hold the roll shaft. Refer to Figure 14.
4. Remove the four (4) socket head cap screws and then remove the shaft coupling cap.
5. Measure the overall length of the roll shaft to verify that it fits correctly between the transducer
bodies. The journal must be long enough to fully engage the transducer’s shaft coupling, but not
so long that it makes contact with the bottom of the coupling bore. A clearance of approximately
1/16” (1.6 mm) per side should ensure against bottoming.
6. Install coupling bushings on the roll shaft (if being used) and place the roll onto the stationary
portion of the shaft coupling. To be sure that the clamping force is properly transmitted to the roll
shaft align the bushings so that the split coincides with the split of the shaft coupling. Refer to
Figure 14.
7. Install the coupling cap loosely using the socket head cap screws. Do not completely tighten the
screws until you have performed Preloading steps outlined in section 4.6 of this document.
4.6 Preloading
The design of the gimbaled shaft coupling incorporates a feature to accommodate shaft expansion and
contraction. Temperature changes and material differences can cause the shaft to expand or contract,
therefore the coupling needs to provide a degree of axial “free-play” so that the strain beams in the
transducer are not subjected to excessive force. Performing the preloading steps outlined below lets the
transducer accommodate limited amounts of contraction or expansion. As a point of reference, a 100
degree Fahrenheit rise in temperature can cause an aluminum shaft to expand by nearly 0.016” per foot of
shaft. Steel expands only about 60% as much as aluminum.
To pre-load the transducer:
1. Confirm that there is clearance between the end of the roll shaft and the bottom of the coupling
bore (described above) then, tighten the shaft in the coupling at one transducer by tightening the
four (4) socket head cap screws.
2. Check the remaining transducer to be sure that the shaft is loose in the coupling and then, press the
coupling inward by approximately 1/16” (as if pushing it into the transducer body). Hold the
coupling in the pre-loaded state while tightening the cap screws. When you release the coupling,
the free play that you established is evenly distributed between the transducers (half at each
transducer).
Do not defeat the expansion capability by bottoming both transducer couplings while tightening the cap.
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