SIGMA projetor - Manual (Page 47)

MAINTENANCE INSTRUCTIONS
4.16
4 Inspect the swage fittings of each source guide tube to ensure the threads are not stripped or galled.
If the threads are damaged, the use of a 1in-18 tap or die and oil can be used to clean the damaged
area. Using moderate pressure, attempt to twist the swage fitting off the source guide tube. If any
movement is possible, remove from service and replace the swage fitting. Inspect the source guide
tube near the swage fitting for breaks and bulging, remove from service and send to a service center
for repairs. Inspect the exposure head (source stop) for excessive wear or perforations on the end-
stop and the side where the collimator (beam limiter) is mounted. Damaged fittings or exposure
heads on source guide tubes can be replaced at a QSA Global service center. If the swage fittings
are not damaged and are securely attached to the source guide tube, apply a light coat of grease to
the threads and install the protective covers over the fittings.
Misconnect Test After Reloading Sealed Source into the Exposure Device
After performing the annual maintenance, the complete radiography system must be tested by the
maintenance program administrator or Radiation Safety Officer. A misconnect test on the exposure
device including the radioactive source assembly and wind-out controls effectively tests the integrity of
the entire locking system. This procedure detects long-term wear (or damage) of the interrelated failsafe
system including identify any excess wear on the control cable connector, device locking mechanism and
sealed source connectors simultaneously.
Note: Component wear occurs to both the control assemblies and the device lock assemblies
over time, therefore, to ensure acceptable equipment operation, the misconnect test must be
performed on each device lock assembly and control assembly combination that could be used in
the field. For example, if controls are used interchangeably with more than one specific exposure
device, then each control must be checked with each device to ensure the failsafe system for all
control assembly/device combinations are compliant.
The test should only be performed by personnel that are formally trained, authorized and thoroughly
familiar with annual maintenance procedures. This test is performed by engaging the remote control
connecting plug assembly into the exposure device's locking mechanism WITHOUT first engaging the
control cable connector within the source assembly connector.
The ability to then rotate the locking mechanism from the CONNECT position towards the LOCK position
indicates critical dimensions of the locking system are excessively worn to an unsafe condition. Extreme
care should be exercised to prevent rotating the locking mechanism's selector ring beyond the
LOCK position. If the locking mechanism and remote controls fail a misconnect test the equipment must
be removed from radiographic operations. The equipment must not be used until repairs are performed
and misconnect test results are satisfactory.
During the performance of the misconnect test there is a risk of losing control of the radioactive
source assembly if:
• the components are excessively worn or damaged
• the person performing the test intentionally or inadvertently rotates the selector ring from the
CONNECT position to the OPERATE position
• the person performing the test intentionally or inadvertently pushes the lock slide into the EXPOSURE
mode.
Contact a QSA Global, Inc. service center if you have questions regarding the misconnect test.