Rotor of Traction Motors

Audit of following Work Instructions was done in TM Shop. Report is as follows:-

MIG welding, Shrink ring fitment and dispatch work of Rotor Assembly( W 21.405):-

Points noticed:-

• 
  Protection while welding to be done by Glass Mica sheets as mentioned in para 3.3 of this WI should be done. Can heats conducting metal sheets be used?

• Record of pre-heating current and temperature to be taken while pre-heating should be kept.

• Baking to 300 degrees for 4 hours  after MIG welding as prescribed in para 3.10 of this WI is done.

• Proof turning and ultrasonic testing after baking as mentioned in para 3.11 of this WI  should be done.
• Cleaning after proof turning as mentioned in para 3.12 of this WI should be done.
• Brazing of rotor bars on both sides as mentioned in para 3.13 of this WI should be done.
• Since so many steps are to be followed and rotor still works, WI modification should be carried out.
• Spray Painting of rotor after covering the groove with  nomex paper as mentioned in para 3.20 of this WI should be  done.