Covers testing for dealing with KF joints by the gate valve on the FE.

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Feb 20: Tested two KF clamps joints by the gate valve area

• When undoing the KF nuts, recommend starting with torque tool, then undoing by hand to prevent excessive loading in the updated retained design or prevent losing the nut if we decide to not have the nut retained.
• Having a retained design may help by giving the hot cell operator feedback when the nut is brought out as far as it can.
• During testing, we did not capture possible side loads on the 'free' side of the KF joint, though after reviewing the TISA version of the connectors, they may not be as strongly loaded so this is likely not a problem. Instead, the problem will be preventing the 'free' side from being dropped.
• A 'captive' KF gasket may be advantageous to better ensure the joint is re-done properly when servicing and to minimize the risk of the gasket falling out (although during testing this risk seemed minimal).
  • After initial search, an off-the-shelf solution does not seem to exist, would likely have to be modified in house, which is undesirable.
• We were working with 'old' designs for the clamps without captive nut on the clamp and with shorter screw and smaller hex size on the nut.
• The external clamp had a larger nut than the rear, more realistic to what we understand will be implemented in the redesigned clamps.
• For testing both, we used only the clamp body with the bigger nut.
  • To move clamp body from the exterior joint to the interior joint, we had to remove the HV shielding on the back
  • We noticed that the screw on the HV shielding was not captive but we recommend for this to be changed to be captive is possible
• Both KF joints were successfully serviced (undone, gasket accessed, re-done)
  • We did not test replacement of the gaskets, a tool is recommended to aid this
  • Access to clamp nut on exterior joint is ok, interior joint access could be better (orientation not optimal, could be adjusted by rotating the bracket)
  • Larger size KF line that crosses in front of the interior line was not tested due to missing clamp assembly.
  • The larger KF line will likely need to be disconnected and moved out of the way if we need to service the interior KF joint.
  • Again, a caveat with the successful servicing test is that we did not experience any side loads and the 'free' side was held in place by hand when the joint was re done and the clamp closed
    • When holding the 'free' side with the manipulator, it is difficult to position it such that the clamp can close enough to swing the nut back in place (full contact around the gasket difficult)
    • 'Closing' the clamp back up if the lines are aligned and flush is very difficult to do with a single manipulator (if the second manipulator is used to hold the 'free' side in place).
    • Using an allen key to 'fish' the nut on the clamp when re-doing is useful.

Testing will likely be revisited when we receive the updated clamps, specifically that for the larger, untested, KF joint.