Hkkjr ljdkj&jsy ea=ky; Government of India - Ministry of
vuqla/kku vfHkdYi vkSj ekud laxBu Railways
y[kuÅ& 226011 Research, Designs & Standards
e-mail: Organizaton, LUCKNO 0 226011
dsetm@rdso.railnet.gov.in Fax: 91-0522-2452581
Telephone : 0522-2465716
No. EL/2.2.13 Date: As signed
To Principal Chief Electrical Engineers:
1. Central Railway, Mumbai CST-400001 e/; jsyos] eqEcbZ ]lh,lVh&400001
2. East Central Railway, Hazipur-844101 iwoZ e/; jsyos] gkthiqj&
844101
3. East Coast Railway, Chandra Shekharpur, iwoZ rVh; jsyos] pUnz'ks[kjiqj]
Bhubaneshwar-751017 Hkqcus“oj&751 017
4. Eastern Railway, Fairlie Place, Kolkata -700 iwoZ jsyos] Qs;yhZ Iysl] dksydkrk&700
001. 001
5. North Central Railway, Block-A, mRrj e/; jsyos] Cykd ,&2]
Subedarganj, Allahabad- 211 033 lqcsnkjxat bykgkckn & 211 033
6. Northern Railway, Baroda House, New Delhi- mRrj jsyos] cM+ksnk gkml] u;h
110001 fnYyh & 110001
7. North Western Railway, Jaipur- 302 006 mRrj if'pe jsyos t;iqj& 302006
8. North Eastern Railway, Gorakhpur-273001 mRrj iwoZ jsyos xksj[kiqj& 273001
9. North East Frontier Railway, Maligaon, mRrj iwoZ QzsUVh;j jsyos ekyhxkWo
Guwahati-781011 xqokgkVh&781011
10. South Central Railway, Secunderabad nf{k.k e/; jsyos] jsy fuyk;e]
-500371 fldanjkckn&500 371
11. South East Central Railway, Bilaspur - nf{k.k iwoZ e/; jsyos] fcykliqj & 495 004
495004
12. South Eastern Railway, Garden reach, nf{k.k iwoZ jsyos] xkMsZujhp] dksydkrk&700
Kolkata-700043 043
13. Southern Railway, Park Town, Chennai - nf{k.k jsyos] ikdZ Vkmu] psUubZ&600003
600003
14. South Western Railway, Hubli- 580020 nf{k.k if'pe jsyos gqcyh&580020
15. West Central Railway, Jabalpur-482001 if'pe e/; jsyos] Tkcyiqj & 482001
16. Western Railway, Churchgate, Mumbai-400 if'pe jsyos] ppZxsV] eqEcbZ& 400 020
020
17. Chittaranjan Locomotive Works, fpRrjatu jsy batu dkj[kkuk]
Chittaranjan-713331(WB) fpRrjatu & 713331
18. Banaras Locomotive Works, Varanasi -221 cukjl jsy batu dkj[kkuk]
004 okjk.klh&221004
19. Patiala Locomotive Works, Patiala (Punjab)- पटटियाला रे ल batu कारख़ाना] पटटियाला
147003 (पंजाब)&147003
Amendment No.-2
Special Maintenance Instruction No. RDSO/2013/EL/SMI/0278 (Rev’0’) dated
24.12.2013
Sub.: Amendment no-2 of SMI-0278 Rev ‘0’ dated 24.12.2013 for fitment of Traction Motor
Drive End Bearing NU2236 in 3-phase TM type 6FRA6068.
Ref.: Special Maintenance Instruction No. RDSO/2013/EL/SMI/0278 (Rev’0’) dated 24.12.2013
and its amendment no.-1 dated 08.03.2021
Amendment no.-2 of Special Maintenance Instruction no. RDSO/2013/EL/SMI/0278 Rev
‘0’ dated 24.12.2013 for fitment of Traction Motor Drive End Bearing NU2236 in 3-
phase TM type 6FRA6068 is being issued and enclosed herewith for necessary action.
ANURAG Digitally signed by
ANURAG AGARWAL
AGARWAL 16:59:04 +05'30'
Date: 2022.03.29
(Anurag Agarwal)
For Director General/Electrical
Copy to:
Principal Chief Electrical Engineer, Chittaranjan Locomotive Works, Chittaranjan-
713331: Kindly inform to all traction motor manufacturers accordingly
ANURAG Digitally signed by
ANURAG AGARWAL
AGARWAL 16:59:58 +05'30'
Date: 2022.03.29
(Anurag Agarwal)
For Director General/Electrical
s Hkkjrljdkj&jsyea=ky; Government of India - Ministry of
vuqla/kkuvfHkdYivkSjekudlaxBu Railways
y[kuÅ& 226011 Research, Designs & Standards
e-mail: Organizaton, LUCKNO 0
dsetm@rdso.railnet.gov.in 226011
Telephone : 0522-2465716 Telex: 0535-2424 RDSO-IN
Fax: 91-0522-2465716
No. EL/2.2.13 Date: As signed
Amendment No.-2
Special Maintenance Instruction No. RDSO/2013/EL/SMI/0278 (Rev’0’) dated
24.12.2013
Sub.: Amendment in SMI-0278 Rev ‘0’ dated 24.12.2013 for fitment of Traction Motor Drive
End Bearing NU2236 in 3-phase TM type 6FRA6068.
Ref.: Special Maintenance Instruction No. RDSO/2013/EL/SMI/0278 (Rev’0’)
dated24.12.2013 and its amendment no.-1 dated 08.03.2021
1. Recently DE side bearing seizure cases in traction motor type 6FRA6068 is showing
increasing trend specially in last two years. In most of the DE side deflector (outer
labyrinth) is coming out as reported by Railways.
2. Improper interference between bearing components and rotor shaft is one of the reasons
of such type of failures. Interference between bearing components & rotor shaft must be
as per MS-0415. During examination it was found that improper taper /dimensions of
dummy pinion is one of the reasons for maintaining improper interference.
3. It is mentioned that rotor shaft of the traction motor is hollow from one side. Shaft of the
dummy pinion is inserted into the rotor shaft & final machining/grinding of outer surface
of shaft is done. Hence the different seating diameters (of inner racer & labyrinths) of
rotor shaft OD are maintained with dummy pinion.
4. As per instructions /procedure (as per SMI-0278 & its amendment-1), fitment of inner
labyrinths, inner racer & outer labyrinth is done with dummy pinion and after complete
assembly of TM, dummy pinion is removed & actual pinion is finally inserted.
5. If there is any discrepancy in dimensions/taper of dummy pinion or in actual pinion then
there will be difference of swell on rotor shaft during insertion of actual pinion which
will result in improper interference between labyrinths /inner racers & rotor shaft. There
is no guarantee that the interference maintained at different locations will remain the
same.
6. So, keeping in mind the importance of dimension/taper of dummy pinion, CLW is
advised to review the QAP of manufacturing process of rotor assembly for ensuring
100% measurement of dimension/taper of dummy pinion during procurement/assembly.
7. Some Zonal Railways (CR, SCR etc.) have started assembly of traction motor with actual
pinion in place of dummy pinion to avoid improper interference due to incorrect
dimension/taper of dummy pinion.
8. Keeping in view of above facts, it is advised to assemble the traction motor with actual
pinion in place of dummy pinion. Accordingly procedure of assembly of TM as
mentioned in SMI-0278 needs to be modified. Existing clauses of SMI-0278 are modified
as below :-
SN Clauses of Existing Modified
SMI-0278
Ensure dummy pinion is inserted in Remove dummy pinion as per
1. 4.1.3
the shaft before mounting of inner procedure prescribed in SMI-
racer. Measure the bore diameter of 0278 and mount the actual
inner racer and bearing seat pinion as per procedure given
diameter and ensure there shall be in revised clause 4.5 of SMI-
interference between 50-65 micron. 0278 (mentioned below).
This can be done by selecting right Note down the pinion
match of inner racer for a given advancement and rotor shaft
shaft. Record these measurements. diameter at inner racer seat,
inner & outer labyrinth seats.
Measurement of rotor shaft dia
at different location will be
useful for ensuring desired
interference between rotor shaft
& bearing components as per
MS-0415.
2. 4.2.1 Inner racer Fitment of inner labyrinth
After following necessary &inner racer
precautions, heat the inner racer In case of WAG9 TM:
upto 120°C and mount the inner Actual pinion will remain
racer and hold it in the position till inserted. After following
it cools down. Measure the swell of necessary precautions, mount
inner racer and record it. the inner labyrinth & inner
racer. Both must be heated on
induction heater & temperature
must not exceed 120 degree.
During the mounting, racer
must be hold till it cools down.
In case of WAP7 TM:
Remove the actual pinion and
mount the inner Labyrinth &
racer.
3 4.2.2 Outer racer Fitment of outer racer
Clean The end frame and all its No change
tapped holes with compressed
air/sand paper.
Fix the expanding dowel on the
hole above the greasing nipple
hole by driving the ball of
expanding dowel with the help
of metallic rod and hammer.
Insert the grease with grease
gun in the re-greasing bore such
that the grease just fills the
entire bore. Remove the first
grease which comes out of the
bore of the regreasing hole.
Clean the inner labyrinth and
apply grease on half of the
circumference with grease gun.
Insert the inner labyrinth by
matching its slot with the
regreasing hole with the help of
copper hammer.
Take the cylindrical roller
bearing, apply grease with
grease gun inside the cylindrical
rollers. Make it uniform by
hand.
Heat the bearing bracket up to
120oC and insert the outer racer
in it .
Clean the bearing cap and apply
grease on half of the
circumference with grease gun
& assemble the sealing ring.
Apply the anti rust compound
on the bearing cap and the end
frame surface.
Apply the anti-rust compound
on all bolts.
Mount the bearing cap by
matching its slot with the re-
greasing bore hole.
Tighten all bolts by torque
wrench.
4 4.2.3 - Assemble the TM as per
maintenance manual. Finally
mount the outer labyrinth.
In case of WAP7 TM, finally insert
the actual pinion as per revised
procedure in clause 4.5 mentioned
below
3. 4.5 a. Clean the tapered fit by cloth a. Clean the tapered fit by cloth
and paper and thinner. Dry it. and paper and thinner. Dry it.
Clean the pinion with paper and Clean the pinion with paper
cloth and all its holes by and cloth and all its holes by
compressed air. Pinion and the compressed air. Pinion and
shaft bore must be free of any the shaft bore must be free of
grease/rust/ colour. any grease/rust/ color.
b. Mount the pinion on the shaft as b. Mount the pinion on the shaft
per the procedure given in the as per the procedure given in
maintenance manual. the maintenance manual.
c. Measure the distance between c. Measure the distance between
gauge face & pinion teeth face. shaft face & pinion teeth face
It should be 15±0.3 mm (say a). before applying pressure. It
The pinion shall travel 12 mm should be around 15-17 mm.
inside the shaft and after d. Now start applying pressure.
mounting of pinion, it shall be Ideally pinion shall travel 12
a-b=12±0.1 mm, mm (+/-0.1mm). However, it
There shall be travel of 12±0.1 is advisable to measure racer
mm of pinion during application seating dia during pinion
of pressure. insertion. Make sure racer
seating dia must not exceed its
maximum limit i.e. 180.068
mm.
e. During pinion mounting,
pressure of pump should be
increased up to approximately
1700-1900 bar. Ensure that
under no circumstances
pressure exceeds 2000 bar.
ANURAG Digitally signed by
ANURAG AGARWAL
AGARWAL Date: 2022.03.29
17:00:33 +05'30'
(Anurag Agarwal)
for Director General Electrical
