Cleveland Motion Controls ULTRA ISC CARTRIDGE TRANSDUCER REV AA - Manual (Page 30)

U LTRA S ERIES S TATIONARY S HAFT T RANSDUCER T ECHNICAL M ANUAL MAN-70430-0 R EV AA
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Tighten the shaft coupling cap. Be sure that the size of the gaps on each side of the roll shaft are
approximately equal in width. Refer to Figure 14
.
EQUAL GAP ON BOTH SIDES
REMOVABLE CAP
STATIONARY HALF
OF SHAFT COUPLING
ROLL SHAFT
ALIGN BUSHING AND
CAP SPLITS
(DEAD)
Figure 14 - Correct Shaft Coupling Installation
4.7 Minimizing Beam Torque
Rolls often have an uninterrupted shaft that extends to form the journals. Even though the roll may be
described as having a “dead shaft”, neither journal end can rotate independently of the other. Because of
the twisting force, attempting to rotate one transducer while the other end of the roll is firmly clamped can
result in damage to the transducer. Even though the force may not large enough to cause permanent
damage, they can impair the accuracy and stability of the transducer tension signal.
To minimize the potential for having accidentally stored a residual twisting force in the beams when the
transducers and roll were mounted, we recommend that you use the following steps to adjust and verify
your transducer.
1. Slightly loosen the mounting bolts that secure one of the transducers to the machine frame so that
the transducer is free to rotate about the axis of the roll. Note that a small amount of rotation is
possible using only moderate force. At the outer diameter of the transducer housing, the rotation
might amount to roughly 1/8” of circumferential travel, as each transducer contributes just over
two (2) mechanical degrees of rotational play.
2. Position the transducer at the approximate midway position before re-tightening the mounting
screws. This helps to ensure that the transducers shaft coupling is free to float rotationally. The
residual torsional forces are minimized on the beam assembly.
3. Lightly, twist the roll journal/shaft back-and-forth by hand to verify the amount of available free
play. Approximately one or two degrees of angular free play should be evident.
4.8 Checking The Transducer Mounting
Before preparing to apply force to the transducer(s) and calibrating the amplifier, inspect the load cell to
confirm that it is oriented and mounted in accordance to the installation instructions. Common problems
include:
 Failure to mount transducers on flat (machined) surface.
 Poor shaft alignment that exceeds allowable limits.
 Fastener torque either excessive or insufficient.
 Transducer mis-oriented so that the axis of sensing is not true to the applied force vector
(bisector of the wrap angle).
 Roll is mounted without allowance for shaft expansion/contraction at shaft coupling.
 The transducer is positioned in the web path so that the wrap angel is not constant.
For more information about proper practices for applying calibration, refer to section 4.12 in this
document.