Removal and replacement testing of the stainless VCR lines extending from the HVFT to the piston modules and FE plate is documented in this ELOG.

Exchange of the FE plate water connector lines is documented in a ELOG #79. Exchange of VCR gaskets in the permanent joints is given in ELOG #83.

Photos provided in PDF, download and open to view all, ELOG preview not guaranteed to show all.

Feb 13:

• Connecting VCR joints between PEEK seal water lines at FE plate to welded pipe section from HVFT was tested:
  • Between the two joints, the one that is routed more internally was tested, there are more lines in the way of access to this joint so it is likely the more difficult of the two joints to service.
  • The gas line routed from the back of the FE is routed next to this joint and interferes with servicing slightly.
  • Retaining bracket on HVFT was kept on for the HVFT side of the line to simulate exchanging the VCR gasket only.
  • It is very easy to drop the gasket during this operation, and in a very hard to reach location, would be good to come up with a solution to prevent this or minimize the chance of the gasket dropping into hard to reach crevasses, better if dropped onto lift table.
  • Need to wedge something at the welded tube section to prop up the male VCR side of the joint for access for VCR exchange, large handled wrench worked best during testing.
  • Recommend end-mount gasket to minimize risk of losing, end loaded gaskets are more secure than side loaded ones.
  • Multi-pin bundle was not present during testing, in practice it will likely further obstruct the joint and increase the risk of dropping a VCR gasket, recommend unpinning FE side of the bundle and getting it out of the way in the real operation.
  • Due to the way that the lines are welded, they tend to be misaligned unless 'turned' by the manipulator into orientation, a camera mounted on the base jig, a dedicated stand, or even on the table would be good to get an alternate view and ensure that the threads are aligned during servicing. This creates side load onto the threads and makes 'hand tightening' with the manipulator fingers difficult to do.
  • By hand, the welded tube section looks like it could be removed without issue, assuming the VCR joints are undone, the FE plate side was tested separately.
  • A design change suggestion that was discussed was the addition of some kind of retainer or other feature on the line routing trays on the FE to hold the male side of the VCR joint and help simplify the gasket exchange operation.
  • Ultimately, however, we were able to successfully exchange the gasket in this line.
• The long gas lines between the HTV and the service tray was tested by hand:
  • the electrical connectors on the FE plate (mass markers) were not present during testing, but we believe it should not have affected the outcome.
  • the line(s) were successfully 'fished out' by hand, we believe it can go through the FE plate opening both ways (from the back or through the front) without too much issue.
  • the gas line brackets on the FE plate needs to be taken off in order to exchange the top gas line
  • the critical operation for the gas line will be removing the screws from the bracket, if it is dropped there is a high risk of it dropping into the FE carriage mechanisms and be difficult to retrieve
  • a catch tray is strongly recommended to prevent this
  • a hand tool to grab onto the sealing faces of the gas line is recommended (see previous observations in ELOG 72)
• Most other lines between the HVFT and the service tray look like they could be pulled out and returned without having to remove other lines, but we will check for sure when we revisit testing these lines.
  • Note: one slightly concerning line is the one routed in along the lowest layer, obstructed by all other lines above.

We will resume testing by attempting to replace the gas lines with the manipulator