Grant Minor wrote this e-mail today:

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Hello all,

During our planned operation of transporting TM4 from a storage silo to the Hot Cell, we had a problem with the East-West bridge drive on the Target Hall crane.  The crane bridge is currently stuck in position over the silo area.  We were unable to complete the transport operation.  TM4 has been placed back down into the silo and the crane hook block has been disconnected from the module lifting yoke.

We have been on the phone with Norelco this afternoon and have determined the likely cause of the problem.  There is a splice joint in the crane rails at this position, where a small gap exists between the rail sections.  If the crane bridge is stopped during operation such that the wheel comes to rests in this gap, the crane motors have insufficient torque for the wheel to overcome the gap and ride back onto the rail.  The Norelco tech Mike Smith remembers encountering this problem several years ago (before my time) but cannot remember how it was overcome.  The fix likely involved moving the wheel out of the gap with pry bars.

Target Hall Survey Needed at or before 7:00 am, Wednesday Oct 9th (Lynne, Fiona, Danka, Max or Dano?)

Mike Smith and possibly a few others from Norelco will come tomorrow morning at 7:00am, and require access to the Target Hall.  Since we have opened the Hot Cell in preparation for the module move, we will need a survey as early as possible to allow Mike and his crew to enter the hall without a suit and respirator.

Most of the Remote Handling group will be off-site for a Division meeting, but Travis and Maico will stay for the day to accompany the Norelco guys and help with the problem assessment.

Travis: Please take Mike to the control room when he arrives, one of the cameras is currently zoomed in on the wheel and problem rail section.

Maico: Scaffolding may be required to get access to the crane rail.  Unfortunately we don't have an operational crane to transport a man-lift into the hall ;)  Please see what you can do to get this ready in case we need it.  Max's leak check might have to go on hold until we get this resolved.  Please take responsibility for ensuring correct Fall Protection procedures are followed.  This means that nobody should be walking up on the crane rail unless they are tied in with harnesses, or there is scaffolding directly under them.

I can be reached on my cell phone at 778-319-4612.  The Division meeting is on UBC campus so I can return to TRIUMF fairly quickly if needed.

Thank you all for your assistance,

Grant

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A photo of the THall camera view of the bridge wheel at the rail splice is attached, as well as Mike Smith's crane inspection report from March 2013.