Instru cti on Bull etin no. MP.IB.EM MP.IB.EM.08 .08.70 .70.09 .09
Government of Indi a, Ministry of Railways Railways Research Research Design Design s & Standard Organis ation Manak Nagar, Luck now – 226 226 011 011 Inst ruct ru ctio ion n Bul leti n no.MP.IB.EM.0 no.MP.IB.EM.08.7 8.70.0 0.09 9
Dated 29.10. 29.10.200 2009 9
1.0 TITLE: TITLE: Instructions for arresting loosening/ breakage of screws fitted in roller suspension bearing unit and gear case of Alco locomotives. 2.0
BACKGROUND: BACKGROUND: The fitment procedure and maintenance of the suspension bearing arrangement on ALCO locos was standardized through MP.MISC.- 141 (Rev.01), September 2006 (Schedule of standard examinations of 3100 HP and 3300 HP Diesel Electric Locomotives fitted with Roller Suspension Bearings), MP.MI-20 of Nov. 2001, MP.MI-22 of March’2002 and MP.IB.EM.01.22.09.
2.1
3.0
In view of continued complaints by Diesel sheds regarding loosening of cap screws, some of the maintenance practices advised in MP.IB.EM.01.22.09 have been studied afresh and this additional instruction bulletin is being issued. OBJECT: The object of this IB is to lay down guidelines to prevent loosening of screws of suspension tube and gear case during locomotive run.
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DETAIL S OF STUDY/ EXPERIMENTATION DONE: Study has been carried out in diesel sheds regarding problem of loosening of screws fitted at the locations. These screws become loose due to vibrations generated on locomotive at run. The torque value of the screws has been revised upward along with instruction to use thread locker vide IB no. MP.IB.EM.01.22.09. In order to arrest cases of loosening of these screws a new design of washer known as ‘Disc-Lock washer’ has been developed for application at these locations and demonstrated in Itarsi and AMV Diesel Sheds. This washer has been found to be effective in preventing loosening of these screws.
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APPLICATION APPLICA TION TO CLASS CLA SS OF LOCOMOTIVES: LOCOMOTIVES: All Alco design of locomotives locomotives with MSU arrangement.
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INSTRUCTION CONTENT: In order to arrest loosening/ dropping/ breakage of screws of suspension tube components following instructions are being issued; Page 1 of
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Instru cti on Bull etin no. MP.IB.EM.08.70.09
i)
This IB shall give an option to the sheds etc. to switch over to Disc Lock washer in case they are unable to arrest the loosening by application of thread locker/ use of higher torque. In case the Disc lock washers are used, revised torque values shall have to be used as given in table-I.
ii)
Provision of disc lock washers shall be done on all M-12 and M-36 bolts fitted on wheel/ gear end of MSU components and gear case as per table below: Table- I S. No.
1
2
3 4
*
Size of Screw/ Location /Qty.
Part no./ Order
Torque with Disc Lock Washer (Kg.cm) 418 to 503
Torque with Conventional Washer (Kg.cm) 800 to 1000
M12 x L70 at RWE of MSU Qty. = 8 nos. M12 x L90 at GWE of MSU Qty. = 8 nos. M36 of MSU Qty. = 8 nos. M36 of gear case, qty. for; TM4907 & TM5002 = 2 nos. each. TM4906 = 3 nos.
105-01
418 to 503
800 to 1000
117-01
12100 to 14500
14500
117-01
20700 to 24400 (Dry condition)
20700 to 24400 (Dry condition)
No. *
* (CB) 105-01
* (CB)
Order no. as per M/s V.M.R.Engineering Services Pvt. Ltd. Instructions “Solves the problem of fastener failure”.
* (CB) – Counter Bore. Procedure of fi tment: a) Place a pair of Disc-lock washer at M-12 cap screws and M-36 bolts on MSU and M-36 bolts on gear case. b)
Both the disc lock washers should be applied such that the sides with cams are mated together as shown under;
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Instru cti on Bull etin no. MP.IB.EM.08.70.09
c) Location of b olts o n suspension tu be and gear case
Suspension Tube Indicating Location of Mounting B olts & Disc-Lock Washer Page 3 of
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Instru cti on Bull etin no. MP.IB.EM.08.70.09
Traction Mot or (TM4907) Gear case Indic ating L ocatio n of Mounti ng Bolts & Disc-Lock Washer
Precautions whil e using disc loc k washers: i.
Disc lock washers should be applied such that the sides with cams are mated together
ii.
Washers of sizes matching with the fastener should only be used as given in table-I.
iii. The threads should be properly cleaned and recommended torque values to be used for tightening the fasteners. iv. The disc lock washers are re-usable based upon its condition and soundness. As in case of conventional fasteners before re-use, disc lock washers should be carefully examined. If deep scoring on the cam surfaces or the seizing ridges getting worn/ flattened, the washers must not be reused. v.
7.0
Sometimes, bolts/ screws are used to push/ jack an assembly into place. This practice should not be followed where disc lock washers are used. They must not be used to push/ jack an assembly into place. Disc lock washers must be installed when the assembly is in place and ready for tightening. MATERIAL REQUIRED AND SOURCES OF SUPPLY: Material -
As given at Table- I.
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Instru cti on Bull etin no. MP.IB.EM.08.70.09 Sources: •
M/s VMR Engineering Services Pvt. Ltd., 20, Paras Majestic, E-8, Area Colony, Bhopal- 462 039, Tel: 07480-231056, Fax: 0755-2560483, Mobile: 09300811757 (Contact person: Mr. Manish Vichitra).
Note: Alternately, similar material is also available from M/s Fair Field Equipment Pvt. Limited, 40, Strand Road, 2nd Floor, Room No. 14, Kolkata for Nord Lock Washers. Small orders may be placed on this firm also, its efficacy evaluated and reported to RDSO.
8.0 ADDITIONAL INFORMATION: -
Nil -
9.0 AGENCIES AND SCHEDULE OF IMPLEMENTATION: All Zonal Railways DLW, Varanasi DCW, Patiala 10.0 DISTRIBUTION: As per enclosed list. 11.0 REFERENCE: i) Sr.D.M.E, N.E Railway, Gonda letter no. M/Dsl/CS/Misc/02/783, Dated 11.08.2009 indicating problem of loosening of cap bolts fitted on suspension tube. ii) MP.IB.EM.01.22.09 Instructions for arresting loosening/ breakage of bolts/ cap screws fitted on MSU in Alco locomotives.
(Vivek Khare) for Director General/MP
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