ISAC Storage Vault Door Re-alignment (April-May 2024) 

Issue

• Rollers gouging and marking on roller supports, testing shows door shifts at least 185 thou on structural beam when fully open vs. fully closed
• door misaligned: 1/4" laterally, slight rotation (~1/16" difference across closed door gap).

Repair

• Moved left structural beam (facing front of door) inward 1/4" at post.
• Loosened drive system to shift door over via crane to average laterally (1/8" shift) towards center,
• Attempted to fix door rotation with crane, door would not settle down perfectly flush, but got slight improvement 
• Adjusted limit switches for fully open and closed (due to the adjustments made previously, needed to realign limit switches) - adjusted flag for final close back by ~1/4"; adjusted limit switch at back of vault forward ~1/4" 

Verification 

• Unloaded vault door actuation tested multiple times with no issues, door returned to same position every cycle, no interferences during travel
• Vault Door actuation tested with trays 4 and 6 engaged, no issues
• All pails accessible when open
• Tested open and closed limit switches: the open limit switches are working properly; the closing soft and hard limit switches are slightly close together, causing the door to just "bump" the vault when closing, The scale of this is OK for current operation, will be adjusted when the ISAC Target Hall Controls Overhaul is done
• Tested and reset Emergency override mechanism - works properly

Outstanding Tasks

• Will paint marks on structural supports to track if problem reoccurs - update ELog when complete 

System State: Operational

See attached file for details