CDZ4-175 Set-up & Drill and Tap

Gary (0498 762 352), who has been buying CDZ4-175 for years. He has had trouble with the last 2 batches.

When he tightened the screws, he could feel them bottoming out before the anode was clamping around the shaft. To resolve this he drilled out the bottom of the holes, but this didn’t resolve the problem.

The Male lugs were also too long by about 1mm, so he ground them down. Once he did that, they fit snuggly in the female recess.

LS suggested that this is result of whoever is tapping the threads not undertaking assembly checks at set up of tapping or during course of tapping.

If the holding jig is loose the casting can tilt in the jig and the tilt can cause a difference in the depth that the tap travels resulting in a shorter and or longer thread (mostly shorter) which would result in the anode not being able to clamp properly around the shaft. Or can be simply that the tap stroke depth has been set too shallow.
Sam to conduct toolbox talk to re-educate on correct procedure including multiple checks during tapping (especially a recheck upon a tap breakage) to ensure that we are catching it prior to assembly.
28AUG24: There was an issue with the length of the pins meaning the fasteners bottomed out before they fully tightened. New pins were fabricated and no further incidents have been reported, so this issue will be closed.

Verification –
Reported by –BL
Closed by –BL
Date closed –August 28, 2024