MTS Series 215 Rotary Actuator - Manual (Page 36)

Series 215 Rotary Actuator Product Manual 36
Adjusting Actuator and Torque Cell Concentricity
Installation
2. Rotate the V-block around the rotor shaft circumference while
simultaneously reading the pilot diameter runout on the face of the torque
cell flange. Check the reading at top and bottom positions.
A. Variation between the actuator reading and the torque cell flange face
must differ by less than 0.0508 mm (0.002 in.).
B. Height adjustments are made by loosening and repositioning the torque
cell. When the proper position has been achieved, re-tighten the torque
cell mounting bolts to the appropriate torque values.
3. Repeat Steps 1 and 2 to ensure that the adjustment was not altered when the
torque cell was re-torqued.
Adjusting Actuator and Torque Cell Concentricity
While centerline heights may be identical and parallel to the base plate or T-slot
table mounting surface, the actuator and torque cell can be eccentric in a lateral
direction. There are two ways to correct for actuator/torque cell eccentricity. The
most appropriate method depends on the type of specimen to be tested. Both
methods are listed below.
Rigid specimen
If the current test application makes use of a rigid specimen, then the specimen
itself can be used to facilitate the alignment process. Because the presumed goal
of the alignment process is to mount the specimen without exerting any
unintentional forces upon it, it may be simplest to loosen the bolts securing the
reaction bracket to the table and then place the specimen in position.
When installing the mounting bolts, ensure that there are no gaps between the
specimen, flexures, and torque cell. Only after checking that both ends of the
specimen contact the mounting surfaces should the mounting bolts be torqued.
This technique allows the specimen configuration to control the “at rest” position
of the reaction bracket. Once the specimen is securely positioned, the reaction
bracket bolts may be torqued to the proper value. Do not use the mounting bolts
to pull the reaction bracket into position.
Flexible or fragile
specimen
If the current test application uses a flexible or fragile specimen, then the
following procedure must be used to correct for actuator/torque cell eccentricity.
1. Attach a dial indicator to the actuator rotor shaft using a magnetic V-block
for the base.
2. Rotate the V-block around the rotor shaft circumference while
simultaneously reading the pilot diameter runout on the torque cell flange.
3. Adjust the torque cell position for an acceptable level of eccentricity by
loosening the reaction bracket. The acceptable level of eccentricity is
determined by the test requirements.
4. After positioning the torque cell, re-tighten the mounting bolts to the
appropriate torque values.
5. Recheck the centerline height and adjust as required.