Incorrect stacking of rotor laminations during the rotor stacking process could result in uneven flux distribution or misalignment of the stack. Potential causes include operator mistake when measuring stack lengths or extension lengths of holding rods. Current controls include pictorial work instructions, measuring tapes calibrated for lengths, and quality checks of stamped keys and guiding rods.

1. Revision: 00
Date: 01/09/2010
Process Name:- Rotor Stacking Process Responsibility:- FMEA Number:-
Frame:- Generic Prepared By:-
Core Team:- Part Number:- FMEA Revision No. / Date :-
24 (Max. Value of S, O, D is 5)
S O D R
LSA LSA LSA LSA LSA E C E P S O D R
462 472 491 491 50.2 V C T N E C E P
1000 kVA (S) (O) (D) V C T N
x x x x x
Incorrect Stack
Length
Mismatching with
Stator stack
Operator Mistake
Pictorial Work
Instruction prepared
WI-20-002
Checked by QC
Variable flux
distribution
Measuring Tape not
calibrated
Data sheets for stack
lengths available
Quality basic audit
Uneven thickness of
laminations
Stacking is done in 4
parts rotating 180° in
WI.20.002
x x x x x
Incorrect Holding
rod Extension
length
Winding overhang
may come out
3 Operator Mistake 1
Pictorial Work
Instruction prepared
WI-20-002
Each holding rod
measured by operator
1 3
x x x x x Improper Welding
Breaking of welding
joint
Operator mistake
Work Instructions
prepared WI-20-007
Operator checks
introduced in job
cards
loosening of
Stampings
Poor quality of electrode
Welder Qualification
test
High temperature of
damper
Improper setting of
welding machine
parameters
Preventive
maintenance of
Machine done
Quarterly
x x x Shifting in stack
lamination mis-
alignment
High unbalance in rotor
Pictorial Work
Instruction prepared
WI-20-002
Manual checking by
operator
wrong
perpendicularity
stack not properly made
(4 parts rotated of 180°)
WI.20.002
Insulation failure
(HV Fail)
Worn out guiding rods
x x Shifting in stack
Insulation failure of
copper wires
Key of rotor lamination
not stamped properly
Guiding rods are used
for checking the
Manual checking by
operator
Work Instruction to be
updated
x x x x x
Burrs on the
stamping
Gap between
stampings
3
Stampings not rotated by
180° after stacking one-
fourth of the stack every
time
3
Pictorial Work
Instruction prepared
for visual display of
stacking WI.20.002
Stacking operator to
check the burr before
stacking.
1 9
Rotor Stacking
ACTION RESULTS
PROCESS FUNCTION/
REQUIREMENTS ACTION TAKEN
RECOMMENDED
ACTION(S)
RESPONSIBILITY &
TARGET
COMPLETION DATE
Threshold Value of RPN:-
Page: 1/1
Generic FMEA
PROCESS FAILURE MODE AND EFFECTS ANALYSIS (P-FMEA)
Rev No. 02 - 22.04.2011
POTENTIAL CAUSE(S)/
MECHANISM(S) OF FAILURE
CURRENT PROCESS
CONTROLS
PREVENTION
CURRENT PROCESS
CONTROLS DETECTION
3 1
POTENTIAL EFFECT(S)
OF FAILURE
POTENTIAL FAILURE
MODE
1 3
4 1 1 4
4 3 1 12KPC 1