Edit: as of May 30, 2022, the modification has been reversed, and the crane is functioning normally as per the manufacturer's limits.
Modifications have been made to the crane to allow for the South Aux Hoist to reach closer to the South wall during the ARIEL Hot Cell installation period. These modifications are temporary, and were considered to be a safer and simpler alternative to the modification proposed by the hot cell contractor workers, which involved installing a sort of come-along on the wall and pulling the hoist closer to obtain the desired reach. The following modifications were made:
- Removal of the bumpers on the south side (T. Kauss). There are no bumpers on the South side of the crane’s bridge currently.
- Modification of the PLC program to reduce the software limit by approximately 4 inches (A. Newsome). The previous soft limit was set at 0.36 m and it was reduced to 0.26 m (~3.9 inch reduction).
These changes have been tested – the crane stops in the expected position. However, it is very close to the wall now. If you are using the crane anywhere near the South wall: exercise extreme caution. The crane automatically slows down when approaching the South wall, and there is plenty of time for the operator to react and further slow the motion by only holding the joystick down at about 20% speed. I strongly recommend operating at about 20% speed when close to the wall (on top of the automatic speed reduction I mentioned).
- These changes are based on Work Permit A2022-01-06-1
- Changes have been noted in the crane’s logbook
See attached screenshot of PLC program indicating that the new limit has been reached.
Contact me (Adam Newsome) for more detailed information.
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