Material kept in open for months gets rusted and laden with dust. Check this out in shell shop. Due to lots of corrosion in the bottom, some machining will again be required before fitment.
Rust ridden bottom.
Above is the photograph of one such cab.
Following shortcomings of TM to be looked into:-
- Less commutator slot depth.
- Slack insulators in TMs.
It is to be seen that commutator slot depth in TMs is not less than standarad.
Problem of slack insulators, need to be watched out.
Rocker rings of TM should be inspected.
Regarding unsuitable Centre Pivot of Casnub bogies : problem of blow holes may be found.
Problem of Mica getting broken in commutator need to be inspected in the shop.
It can be seen that due to Mica getting cracked in between slots( while fixing copper bars), the gap between two slots gets reduced which makes commutator unusable.
Commutator Spider is to be inspected as there can be blow holes/ spongy castings/less material while machining.
Dynamic seasoning plant for commutator should be inspected. Theres is a standard RPM (say 3050) at which all plants should be working . Less than that
may result in less seasoning.