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CASE STUDY OF FAILURE OF HELICAL SPRING OF CARRIAGE _ WAGON

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CASE STUDY OF FAILURE OF HELICAL SPRING OF CARRIAGE _ WAGON Powered By Docstoc
					INTRODUCTION TO COMPOSITES MATERIALS (FRP) AND ITS USES IN INDIAN RAILWAYS.
ARVIND LAL Chief Instructor (Met) IRIMEE, Jamalpur. E-mail – arvindlal65@ yahoo.co.in

INTRODUCTION
COMPOSITE MATERIALS.
COMPOSITES, THE WONDER MATERIALS * WITH LIGHT WEIGHT, * HIGH STRENGTH TO WEIGHT RATIO, * HIGH STIFFNESS AND MORE CORROSION RESISTANCE HAVE COME IN A LONG WAY BY REPLACING THE CONVENTIONAL MATERIALS LIKE WOODS METALS ETC
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COMPOSITES MATERIALS ARE DERIVED BY COMBING OF TWO OR MORE OF MATERIALS WITH THE INTENT OF ACHIEVING SUPERIOR PROPERTIES/ PERFORMANCE COMPARED TO EACH INDIVIDUAL MATERIALS. EXAMPLES- BONES, WOOD, MUSCLE FRP, CERMETS ETC.
FRP- (FIBER GASS REINFORCED PLASTICS ) - IS A LARGE FAMILY OF COMPOSITE MATERIALS. ONE OF THE CONSTITUENT MATERIALS IS CALLED MATRIX WHILE THE OTHER IS CALLED REINFORCEMENT.

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CONVENTIONAL MATERIALS .

METALS AND ALLOYS. (A)
ORGANIC POLYMERS. (B)

CERAMICS AND GLASSES. (C)

B+C –
A+BA+C-

FRP( FIBER-REINFORCED PLASTICS.
MRP( METAL- REINFORCED PLASTICS.

CERMETS

FRP-FEW FACTS.
IN FRP : F – FIBRE. (G-GLASS.) R- REINFORCEMENT.

P- POLYMER ( PLASTICS) BEHAVES LIKE MATRIX.
FIBRE:ANY POLYMER, METAL OR CERAMIC THAT HAS BEEN DRAWN INTO LONG AND THIN FILAMENT IS TERMED AS FIBRE. SOME OF THE FIBRES USED AS REINFORCEMENTS ARE :- GLASS FIBRES, CARBON FIBRES & ARAMID FIBRES

GLASS FIBRE:-GLASS FIBRES ARE THE MOST COMMON OF ALL
REINFORCING FIBRES FOR POLYMER MATRIX COMPOSITES. THE PRICIPLE ADVATAGES OF GLASS FIBRES ARE THE LOW COST AND HIGH STREGTH.

FORMS OF GLASS FIBRE.
1. 2. 3. CHOPPED-STRAND MAT AND CONTIUOUS-MAT. FIBRE GLASS ROVING. WOVEN ROVING. 4. SURFACE MAT.

MATRIX (RESIN) MAY BE :-

POLYMERIC MATRICES:* THERMOSETS;- POLYESTER, PHENOLICS,
METAL MATRICES:AL, Ni AND Ti EPOXY, & SILICONES.

* THERMOPLASTIC:- PS,PE,PC,NYLON-6,6 PEEK ETC.

POLYESTERS ARE WIDELY USED BECAUSE OF THERE LOW COST.

Phenolic resins;- high temperature resistance is required.
Epoxy resins: impart good mechanical properties. Silicon resins:-excellent thermal & elecrrical properties.

GLASS FIBERS:-

Glass fibers are the most common of all reinforcing fibers for polymer matrix composites. The principal advantages of glass fibers are the low cost and high strength. TYPES OF GLASS FIBERS & their nominal formula:E-glass: - Calcium aluminoboroslicate. E (Electrical)- 15 Al2O3, 17 CaO, 5MgO, 8B2O3

S-glass: - Magnesium aluminosilicate.
S (HIGH-STRENGTH) --- 25 Al2O3 , 10 MgO C- glass: - Sodalime borosilicate.

C (CHEMICAL) - 4 Al2O3,13CaO , 3 MgO, 8Na2O, 5 B2O3.

Properties of E-glass & S-glass fibers. Propertied units Density, g/cm3 E-glass 2.54 S-glass 2.49

Tensile strength, MPa
Elastic modules, GPa Range of diameter Um Coefficient of thermal Expansion 10-6/0C

3448
72.4 3.20

4585
85.5 8-13

5.0

2.9

Over 90% of the glass fibers made are E grade. The more expensive S grade is used for the highest strength, and the C grade for chemical resistance. The composition of the glass that is most commonly drawn into fibres is contained as (composition, wt %) – SiO2- 52-56%, CaO-16-25%, Al2O3 –12-16%, B2O3 – 8-13%, 4MgO.

SELECTION OF RAW MATERIALS (FRP)
1.GLASS FIBRE . 2.RESINS. ISOPHTHLATE POLYESTER RESINS IS:6746/72.

EXCEPTIONALLY GOOD CHEMICAL RESISTANT TOWARDS MINIRAL & ORGAIC ACIDS.
3.STABILIZERS:-TO GIVE RESIN A REASONABLE SHELF LIFE. 4. CATALYSTS AND ACCELERATORS:-TO CONVERT RESIN TO A HARD AND INFUSIBLE SOLID WITHIN A SHORT TIME TO MAKE MOULDING POSSIBILITY.

A. FOR COLD CURING:- CATALYST- MEKP
ACCELERATOR-COBALT NAPHTHENATE. B. HOT CURING:- CATALYST-MEKP.

SELECTION OF RAW MATERIALS (FRP)

5. COLOURING MATERIAL & FILLERS

IORGANIC PIGMENTS.
6. MOULD RELEASE AGENT :- PVA IN WATER. HARD WAX SUCH AS CARNAUBA. ARE USED ON POLISHED METAL MOULDS.

FIBRE REIFORCED COMPOSITES. (FIBROUS COMPOSITES)

PARTICLE REINFORCED COMPOSITES (PARTICULATE COMPOSOTES)

LAMINATES COMPOSITES.

ARRAGEMENT OF FIBRE

ARRAGEMET OF GLASS FIBRE.

ARRAGEMET OF FIBRE

ADVANTAGE OF C.M.(FRP) OVER CONVENTIONAL MATERIALS:1. EXCELLENT CORROSION RESISTANCE.

2. LONG LIFE OFFERS EXCELLENT FATIGUE, IMPACT , ENVIRONMENTAL RESISTANCE AND REDUCED MAINTENANCE.
3. LESS NOISY WHILE IN OPERATION & PROVIDE LOWER VIBRATION TRANSMISSION THAN METALS. 4. IMPROVED APPERANCE WITH SMOOTH SURFACES & DECORATIVES.

ADVANTAGES (CONT)

5. WIDE PERFORMANCE RANGE.(BY PROPER SELECTING FIBRES
AND MATRICES)

6. LOW MANUFACTURING COST. 7. SUPERIOR STYLING.
8. HIGH TENSILE STRENGTH (4 to 6 times greater than steel & Al.) 9. MORE FATIGUE LIFE.( UPTO 60% OF UTS). 10. HIGH STRENGTH TO WEIGHT RATIO.( 30 TO 45% LIGHTER THAN AL. 11. ELIMINATE JOINTS & INTEGRATED DESIG COMPARED TO CONVENTIONAL METALLIC PARTS. 12. LESS CHANCE OF THEFT.

FUNCTION OF MATRIX PHASE.
1. IT BINDS THE FIBRES TOGETHER BY VIRTUE OF ADHESIVE FORCE.

2.

IT ACTS AS A MEDIUM BY WHICH VIRTUE AN EXTERNALLY APPLIED LOAD IS TRANSMITTED AND DISTRIBUTED TO THE DISPERSED PHASE.
IT PTROTEST THE INDIVIDUAL FIBRES FRON CHEMICAL REACTION WITH ENVIRONMENT AND FROM THE SURFACE DAMAGE DUE TO MECH.ABRACTION. IT KEEPS THE REINFORCING FIBRES IN THE PROPER POSITIO AND ORENTATION SO THAT THEY CAN CARRY THE INTENDED LOADS.

3.

4.

5. IT PTEVENTS THE PROPAGATION OF BRITTLE CRACKS BY ITS RELATIVE SOFTNESS AND PLASTICITY.

THE ESSETIAL REQUIREMETS OF A GOOD MATRIX MATERIALS ARE :1. IT SOULD BE DUCTILE. 2. THE BONDIG STRENGTH BETWEEN THE MATRIX AND THE FIBRE MUST BE HIGH. 3. IT SOULD BE MORE CORROSION RESISTANCE.

4. IT SHOULD BE MORE ENVIRONMENTAL RESISTANCE.
5. IT SHOULD DETERMINES THE OVERALL SERVICE TEMPERATURE LIMITATIONS.

( POLYMERS ARE LIMITATED TO SERVICE TEMPERATURES BELOW 300c)

COMPOSITES IN RAILWAYS: INDIAN SCENARIO
C.M. HAVE ALREADY BEEN IDENTIFY AS A POTENTIAL MATERIAL FOR ITS APPLICATION IN THE INDIAN RAILWAYS BY THE CONCERTED EFFORTS OF RDSO.LKO & ICF.CHENNAI. WHY NEEDS FOR IR ? 1. HIGHER TRAIN SPEED. 2. LOWER PRODUCTIO, OPERATION & MAINTENANCE COST FOR CARRIAGES. 3. LOWER ENERGY CONSUMPTION. 4 MINIMUM ENVIRONMENTAL IMPACT. 5. LOWER NOISE LEVEL. 6. IMPROVED PASSENGER COMFORTS & AESTHETICS. 7. 8. LESS TRACK WEAR & THE ABILITY TO CARRY GREATER PAY LOADS. TO PROVIDE GREATER VERSATILITY IN TRAIN DESIGN AND OPTIMIZATION OF TRAIN PERFORMANCE.( LOWERING THE CENTRE OF GRAVITY TO ENHANCE STABILITY).

COMPONENTS USED IN IR
COMPONENTS OF COACHES ARE GENERALLY MADE OF FRP-COMPOSITE MATERIALS.
1. WINDOW FRAMES & SHUTTERS.

2.
3. 4. 5.

WALL PROTECTOR IN TOILETS.
TRAYS FOR BATTERY BOXES ( FOR AC & NON AC COACH.) SNACKS TABLE. CHAIN COVER FOR JMP JACK.

6.
7. 8. 9. 10. 11. 12.

FRP AIR GRILL FOR AC COACH.( RAJDHANI)
TOILET PAN FOR GUARAD VAN BRAKE. FRP- TOILET MODULES. FRP-COMMODE ADOPTER. AXLE BOX COVERS. LUGGAGE BIN. PANELS.

COMPONENTS USED IN IR (CONTINUE).
FLOOR, CEILING & ROOF PANELS. 14. MODULAR INTERIOR PANEL & DOORS. 15. DOUBLE DECK FLOORING. 16. INTERNAL SIDE WALL PANELS. 17. EXTERNAL STRUCTURAL SIDE PANELS.

IN ADDITION , RDSO HAS IDENTIFIED A NUMBER OF PARTS FOR REPLACEMENT WITH COMPOSITES I N THE NEAR FUTURE.
THESE INCIUDES. 1. COMPOSITE BRAKE- BLOCKS & BREAK- GEAR BUSHES. 2. FRP-GEAR CASE FOR LOCOMOTIVES. 3. AXLE BOX COVERS (SMC) 4. BERTH & CHAIR BACKINGS.

COMPONENTS USED IN IR (CONTINUE).

5. PANELING IN THE COACHES. 6. ROOF WATER TAKS. 7. TOILET MODULES. 8. LAVATORY CHUTES. 9. WINDOW GUIDES. 10. DOORS. ( MAIN ENTRANCE , SLIDING DOOR FOR 1ST AC COMPARTMENT, INTER COMMUNICATION DOOR IN AC CAOCHES, SLIDING DOORS FOR EMU/DMU, SLIDING/ FLUSH DOORS FOR TOILETS, VESTIBULE DOORS ETC.) 11. CAOPY END FOR EMU/DMU COACHES. 12. TOILET CABINETS. 13. FOLDING TABLES. 14. FUEL IJECTION PUMP COVER. 15. LUGGAGE RACKS ETC.

SOME NEW PROJECTS OR COMPOSITES FOR RAILWAYS: CASE STUDY

“ADVANCED COMPOSITES MISSION ” OF TIFAC
( TECHNOLOGY INFORMATION, FORECASTIG & ASSESSMENT COUNCIL) AN AUTONOMOUS ORGANIZATION UNDER DST (DEPARTMENT OF SCIENCE & TECHNOLOGY GOVT OF INDIA AND DRDO WORKING WITH SOME OF PVT AGECIES ON THE DEVELOPMENT OF COMPOSITES FOR THEIR USES UNDER THE GUIDE LINE OF RDSO & ICF
THESE ARE:-

1. FRP GEAR CASE FOR RAILWAY LOCOMOTIVES.
A.C.M OF TIFAC IN PARTNERSHIP WITH M/S PERMALI WALLACE Ltd, BHOPAL. & RRL,BHOPAL WHY IT IS FELT TO REPLACE THESE BY FRP GEAR CASE. 1. THE HEAVY WEIGHT OF STEEL GEAR-CASE SOMETIMES CAUSES ITS DETACHMENT FROM THE TRACTION MOTOR DUE TO VIOLENT JERKS OR IMPACT OR DAMAGE BY STONE BALLAST WHICH IS VERY COMMON FOR LOCOMOTIVES.

COMPOSITES FOR RAILWAYS: CASE STUDY (CONTINUE)
2. LOSS OF EXPESIVE LUBRICATING MEDIUM BY LEAKAGE.
SL NO. PARAMETER
CORROSION RESISTANCE. WEIGHT PER LOCO

MS GEAR CASE.
HIGHLY SUSCEPTIBLE 134x6=804 KGS

FRP-GEAR-CASE.
NON-CORROSIVE.

1. 2 3

68X6=408 KGS WEIGHT SAVING OF 396KGS

QUALITY OF JOINTS.

COULD BE POOR.

JOINTLESS CONSTRUCTION.

4.

LIFE CYCLE COST.

HIGH 2 TO 3 YEARS.

LOW 6 YEARS.

CASE STUDY (CONTINUE)
SL NO.
5.

PARAMETER

MS GEAR CASE.
DUE TO DEFORMATION MAY POSE PROBLEMS.

FRP-GEAR-CASE.

FITMENT

ENSURES REPEATABILITY

6.

IMPACT RESISTANCE.
HEAT DISSIPATION. FITMENT EFFORTS CHANCES OF FALLING OIL LEAKAGE COST.

VERY GOOD.

GOOD.
DESIGN PROVEN THROUGH FIELD TRIALS.

7.

VERY GOOD.

8.

HIGH.
HIGH CAN BE DISASTROUS.

LOW. VERY LOW. MINIMUM.

9.

10

HIGH.

CASE STUDY (CONTINUE)
•
60-FRP-GEAR-CASES HAVE ALREADY BEEN ORDER. INDUCTED BY IR AGAINST DEVELOPMENT

• EFFOORTS ARE CURRENTLY UNDERWAY TO DEVELOP FRP-GEAR CASES FOR NEW TYPE OF TR MOTOR WITH CYLINDRICAL ROLLER BEARING. • HITACHI MODEL FOR ELECTRIC LOCOMOTIVES.

2. FRP SLEEPERS FOR RAILWAY GIRDER BRIDGES.
THE PROJECT WAS INSTITUTED AT RESEARCH & DEVELOPMENT ESTABLISHMENT(ENGINEER) , PUNE IN ACTIVE COLLABORATION WITH RDSO. • SUBJECTED TO FIELD TRILS AT 3-4 LOCATIONS EACH AT DIFFERENT RAILWAY ZONES.

•VIBRATION DAMPING. & HIGH RESISTACE AGAINST STRENGTH AND WATER RESISTANCE • DYNAMIC PANEL TEST OF 8 LONG SLEEPERS IS CURRENTLY UDERGOING AT RDSO. • THE FULL LENGTH FRP SLEEPERS DEVELOPED BY RTM PROCESS AS PER RDSO.

CASE STUDY (CONTINUE)
3. ENERGY EFFICIENT FRP AXIAL FLOW FANS. OR 1680 MM DIA FAN FOR RADIATOR COOLING FOR DIESEL LOCOMOTIVES
THE PROJECT WAS LACHED IN PARTERSHIP WITH PARAG FANS & COOLING SYSTEMS Ltd, DEWAS & ACTIVE SUPPORTED BY IIT, MUMBAI. EFFICIENCY OF THE FAN HAS BEEN PROVED SUPERIOR TO THE CONVENTIONAL FANS WITH ALUMINIUM IMPELLERS.

4. JUTE-COIR COMPOSITES- AN ALTERNATIVE TO WOOD PRODUCTS.
* M/S DUROFLEX LIMITED BANGALORE.
* APPLICATION.

• PARTITIONING. ( 80% NATURAL FIBRES SUCH AS JUTE & COIR WITH PHEOLIC RESIN)
• FALSE CEILING • SURFACE PAELING • FURNITURE ( SLEEPER BERTH BACHING IN IR COACHES.)

CASE STUDY (CONTINUE)
5. DEVELOPMENT OF

FRP-PULTRUDED

PROFILES.
M/S SUCRO FILTERS Pvt Ltd PUNE & TECHNOLOGY SUPPORT FROM NCL, PUNE.
APPLICATION IN RAILWAYS FOR FRAME SECTIONS FOR DOOR WINDOWS LUGGAGE RACKS STRIPS LADDERS RODS ETC.

Conclusion.
* NOW THE COMPOSITES HAVE BECOME A PART EVERYDAY LIFE. OF OUR * COMPOSITES IMPART AN AESTHETIC APPEARANCE FOR THE RAILWAY COACHES. * NOW WITH THE INTRODUCTION OF LHB COACHES IN THE INDIAN RAILWAYS IN THE NEAR FUTURE, THE USAGE OF COMPOSITES IS EXPECTED TO GROW MORE AND MORE. * GLASS FIBRE IS MOST WIDELY USED REINFORCEMENT.E-GLASS FIBRE HAS EXCELLENT CORROSION AND ENVIROMENT RESISTANCE.

* CARBON FIBRES SHOW NO EXPASION OR CONTRACTION
ACROSS WIDELY TEMPERATURE DIFFERECE, & APPLICABLE TO ELECTRONICS. * SELECTION OF CORRECT RAW MATERIALS & RIGHT MANUFACTURING TECHNIQUE.

CONCLUSION.(CONT)

* DISPOSAL OF USED COMPOSITE MATERIALS. * TESTING FACILITIES OF COMPOENT MATERIALS SOULD BE AVAILABLE AT PU.

THANKS .


				
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