Air Spring Bollow m

AIR SPRING1. SPIGOT – It is the part of top plate which

connects the air path for bellow from bolster. Two ‘o’ rings are provided on this spigot.

2. EMERGENCY SPRING – It is made by layers of metal and rubber. The coach rests on this spring when there is no air, i.e. deflated condition.

3. BELLOW – It is the reservoir which holds the air column for suspension.

4. BASE PLATE – It is the lowest part of air spring and is fitted with Lower Spring Beam. Previously six bolts are used for fixation but now four bolts are used.

MAINTENANCE OF AIR SPRING

• REMOVING DUST MUD AND OIL DEPOSIT IF ANY, ON AIR SPRING IN 4 MONTHS INTERVAL.

• THOROUGH CHECKING OF AIR SPRING, BULGING OF BELLOW, AIR LEAKAGE IN EVERY 4 MONTHS.

• TIGHTENING OF AIR SPRING BOTTOM PLATE BOLTS AND NUTS IN EVERY 4 MONTHS.

• THOROUGH VISUAL CHECK OF AIR SPRING AFTER DISMANTLING (LOWRING FROM BOGIE) DURING POH.

• CODAL LIFE EXPECTED 16 YEARS.

AS PER “MAINTENANCE INSTRUCTIONS ON AIR SUSPENSION FOR DC, AC & AC-DC EMU/HHP DMU COACHES” CMI 9802 (Rev. 2) FEB. 2008 BY RDSO/LKO’S

MANUFACTURER OF AIR SPRING

• There are two manufacturer of air spring bellow

1. M/S CONTITECH.

2. M/S FIRESTONE

• DIFFERENCE – The basic difference between these bellows are the location of Emergency spring. In case of M/S CONTITECH make the bellow is provided on emergency spring. But in case of M/S FIRESTONE the bellow is provided surrounding the emergency spring.

FIRESTONE MAKE AIR SPRING

EMERGENGY SPRINGDEFLECTION UNDER 145 KN IS 13 mm AND STIFFNESS TO 45000 N/mm

FIRESTONE MAKE AIR SPRING BELLOW

DETAILS OF FIRESTONE MAKE AIR SPRING BELLOW

TOP PLATE – THIS IS THE TOP MOST PART OF AIR SPRING BELLOW ON WHICH SPIGOT IS PROVIDED. THIS IS FITTED BY 18 NOS. OF M-10 STUD AND NUT WITH 40 kg-m TORQUE. ONE DISTANCE PIECE OF ANTI RUST POWDER COATED IS FITTED WITH THIS BY THE HELP OF SIX NOS. SOCKET HEADED SCREWS WITH THREAD LOCK.THIS DISTANCE PIECE IS RESTED ON EMERGENCY SPRING WHEN THE BELLOW IS IN DEFLATED CONDITION.

DISTANCE PIECE

SOCKET HEADED SCREWS

DETAILS OF FIRESTONE MAKE AIR SPRING BELLOW

BID SKIRT- THIS IS THE SECOND PART FROM TOP OF BELLOW. THE TOP PLATE IS FITTED WITH THIS BY THE HELP OF 18 NOS. M-10 STUD AND NUT. THE RUBBER BELLOW IS FITTD ON THIS WITH THE HELP OF TWO BLUNT CHIESEL, JUST LIKE THE FITMENT OF TYRE FOR AUTOMIBILES.

BID FOR FITTING BELLOW

STUDS FOR FIXING OF TOP PLATE

DETAILS OF FIRESTONE MAKE AIR SPRING BELLOW

BELLOW- THIS IS MAIN ITEM OF THIS SYSTEM. THIS IS IMPORTED FROM FIRESTONE/USA. THERE ARE FOUR PLYES ON THE BELLOW.

1. OUTER PLY.

2. SECONDARY PLY.

3. SECONDARY PLY.

4. INNER PLY.

1 2 3 4

BELLOW STRUCTURE FOR M/S CONTITECH MAKE AIR SPRING

DETAILS OF FIRESTONE MAKE AIR SPRING BELLOW

DETAILS OF FIRESTONE MAKE AIR SPRING BELLOW

THE YEAR OF MANUFACTURING OF THE BELLOW IS EMBOSSED ON THE BELLOW. THERE IS TWO CONCENTRIC CIRCLES ON THE SURFACE OF BELLOW. THE LETTER IN THE SMALL CIRCLE IS REPRESENT THE YEAR OF MANUFACTURING AND THE NUMBER DOTS REPRESENT THE MONTH OF MANUFACTURING.

DETAILS OF FIRESTONE MAKE AIR SPRING BELLOW

BID RING- THIS IS THE PART WITH WHICH THE OTHER END OF RUBBER BELLOW IS FITTED BY THS SAME PROCEDURE AS FOR TOP END. THIS IS FITTED WITH PADESTAL ASSEMBLY BY THE HELP OF 24 NOS. M-10 STUD AND NUTS WITH 40 kg-m TORQUE.

BID FOR FITTING RUBBER BELLOW

STUD FOR FITTING WITH PADESTAL ASSEMBLY

DETAILS OF FIRESTONE MAKE AIR SPRING BELLOW

PADESTAL ASSEMBLY- AT THE BOTTOM OF THIS, BASE PLATE IS PROVIDED AND AT THE TOP EMERGENGY SPRING AND BID RING ARE FITTED. THERE ARE TWO DOWEL PINS FOR CENTERING OF EMERGENCY SPRING.

EMERGENCY SPRING IS FITTED HERE

BID RING IS FITTED HERE

BASE PLATE IS FITTED HERE

DETAILS OF FIRESTONE MAKE AIR SPRING BELLOW

EMERGENGY SPRING- THIS IS FITTED ON PADESTAL ASSEMBLY BY THE HELP OF FOUR NOS. M-10 BOLT WITH 40 kg-m TORQUE. THIS IS MADE OF RUBBER COVERED WITH METAL PLATE AT BOTH ENDS.

RUBBERMETAL PLATE

HOLES FOR FIXING WITH PADESTAL

DETAILS OF FIRESTONE MAKE AIR SPRING BELLOW

BASE PLATE- THIS IS THE LOWEST PART OF SPRING. THIS IS FITTED WITH PADESTAL ASSEMBLY BY THE HELP OF FIVE NOS. OF M-14 BOLTS AT 60 kg-m TORQUE. PREVIOUSLY THIS WAS OF CIRCULAR SHAPE WITH SIX FIXING HOLES. BUT NOW IT IS OF RECTANGULAR SHAPE WITH FOUR FIXING HOLES.

FIXING HOLES FOR FITTING WITH PADESTAL ASSEMBLY

HOLES FOR FIXING AIR SPRING ASSEMBLY

BASE PLATE

540 PCD

250

400

009

Φ 42

Φ 22

12

MIN

.

525 PCD

Φ 26

Φ 13

12

MIN

.6

HO

LES

EQ

UIS

PA

CE

D

FO

R M

12 C

OU

NT

ER

SU

NK

BO

LT

4 H

OLE

S F

OR

M20

CO

UN

TE

RS

UN

K B

OLT

THE SKETCH OF BASE PLATE AS PER RDSO SKETCH –K1048 ALT. 4 IN “MAINTENANCE INSTRUCTIONS ON AIR SUSPENSION FOR DC, AC & AC-DC EMU/HHP DMU COACHES” CMI 9802 (Rev. 2) FEB. 2008.

DETAILS OF FIRESTONE MAKE AIR SPRING BELLOW

TOP PLATE

BID SKIRT

RUBBER BELLOW

BID RING

EMERGENCY SPRING

PADESTAL ASSEMBLY

BASE PLATE

TESTING OF AIR SPRING

LOAD TESTING- THIS IS DONE AS PER RDSO/LKO’S SPECIFIED PROCEDURE AS MENTIONED IN STR-106.

TEST SET-UP

LOAD TEST PROCEDURE AS PER RDSO STR CK-106 1. PLACE THE AIR SPRING ASSEMBLY IN TEST RIG.2. TEST HEIGHT OF AIR SPRING TO BE MAINTIANED AT 255 ± 5 mm.3. CONNECT AIR SUPPLY TO AIR SPRING.4. RAISE AIR PRESSURE TO 2.0 kg/cm2.5. CLOSE AIR SUPPLY SOURCE.6. TAKE LOAD READING IN kgs AT 2.0 kg/cm2.7. RAISE AIR PRESSURE TO 3.4 kg/cm2.8. CLOSE AIR SUPPLY SOURCE.9. TAKE LOAD READING IN kgs AT 3.4 kg/cm2.10. RAISE AIR PRESSURE TO 4.8 kg/cm2.11. CLOSE AIR SUPPLY SOURCE.12. TAKE LOAD READING IN kgs AT 4.8 kg/cm2.13. RAISE AIR PRESSURE TO 6.0 kg/cm2.14. CLOSE AIR SUPPLY SOURCE.15. TAKE LOAD READING IN kgs AT 6.0 kg/cm2.16. RAISE AIR PRESSURE TO 6.4 kg/cm2.17. CLOSE AIR SUPPLY SOURCE.18. TAKE LOAD READING IN kgs AT 6.4 kg/cm2. If readings in steps 6,9,12,15 & 18 are within ±15% of the value as specifiedbelow, then the air spring has successfully been tested.

TEST RESULT

SL. NO. LOAD PRESSURE

1 4878 kg. (4.88 MT). 2.0 kg/cm2

2 8450 kg. (8.45 MT). 3.4 kg/cm2

3 11,743 kg. (11.74 MT). 4.8 kg/cm2

4 15,000 kgs. (15 MT). 6.0 kg/cm2

5 16,677 kgs. (16.68 MT). 6.4 kg/cm2

LOAD TESTING PROCEDURE

TEST RESULT

LEAKAGE TESTING

THIS TEST IS DONE BY ALLOWING AIR PRESSURE OF 9 kg/cm2 IN AIR SPRING. THE PERMISSIBLE LEAKAGE IS 0.1 kg/cm2 IN ONE HOUR.

FAILURE OF AIR SPRING

MAKE POPULATION LIFE ELAPSED

NO. OF FAILURE

FRCPY

CONTITECH

12 NOS. 07 YEARS NIL 0.00

36 NOS. 3.33 YEARS

36 NOS. 03 YEARS

23 NOS. 1.17 YEARS

16 NOS. 0.42 YEARS

22 NOS. 0.25 YEARS

28 NOS. 01 MONTHS

FIRESTONE

13 NOS. 1.17 YEARS NIL 0.00

04 NOS. 0.42 YEARS

14 NOS. 0.25 YEARS

08 NOS. 01 MONTHS