MTS Series 249G2 Swivels - Manual (Page 18)

Series 249G2 Swivels 18
Safety Practices Specific to Swivels
Safety Information
Each test system operates within a unique environment which includes the
following known variables:
• Facility variables (facility variables include the structure, atmosphere, and
utilities)
• Unauthorized customer modifications to the equipment
• Operator experience and specialization
• Test specimens
Because of these variables (and the possibility of others), your system can
operate under unforeseen circumstances that can result in an operating
environment with unknown hazards.
Improper installation, operation, or maintenance of your system can result in
hazardous conditions that can cause death, personal injury, or damage to the
equipment or to the specimen. Common sense and a thorough knowledge of the
system’s operating capabilities can help to determine an appropriate and safe
approach to its operation.
Safety Practices Specific to Swivels
Read all manuals
Study the contents of this manual and the other manuals provided with your
system before attempting to perform any system function for the first time.
Procedures that seem relatively simple or intuitively obvious may require a
complete understanding of system operation to avoid unsafe or dangerous
situations.
Check for swivel
bearing backlash
During system operation, you should examine the swivel assembly to determine
if there are any visible signs of backlash. If possible, this examination should be
performed immediately after system installation, so that you can better recognize
the “normal” appearance, sound, and feel of a properly adjusted swivel in case an
adjustment becomes necessary in the future.
When a swivel bearing is too loose, the amount of force measured as the actuator
moves from compression to tension can exhibit a small signal discontinuity
during the load reversal. Swivel bearing backlash can also produce an audible
clicking noise from the spherical bearing. This sound might be difficult or
impossible to hear above the noise of the other components in the testing system.
Using a stethoscope can enable you to hear the noise and determine if backlash is
present.
Proper adjustment of the backlash enables the swivel to tilt and rotate without
damaging the bearing or distorting test results. If backlash appears to be the cause
of unacceptable test results, a small adjustment can be made to the swivel. If the
adjustment does not improve the test results, other possible sources of distortion
should be checked.
Locate and read
hazard placards/labels
Find, read, and follow the hazard placard instructions located on the equipment.
These placards are placed strategically on the equipment to call attention to areas
such as known crush points, electrical voltage, and high pressure hazards.