PPT AIR SPRING WORKING ^0 FAILURE[1].pptx

summer industrial training ppt

1. SUBMITTED by :- Sandeep singh Devendra khokher SUBMITTED TO :- M ahendra singh HOD MECHANICAL DIPARtment Presentation on prACTICAL INDUSTRIAL TRAINING AT NORTH WESTERN RAILWAY CARRIAGE WORKSHOP JODHPUR GOVERNMENT POLYTECNIC COLLEGE ,NAGOUR

2. TOPIC :- A IR SPRING, WORKING AND FAILURES

3. CONTENTS :- Introduction of suspension system Types of suspension system Introduction of Air suspension system Working layout of Air suspension system Components of Air suspension system Handling Procedure For Air Spring Testing of air spring assembly on leakage test bench

4. Suspension System in Railway: The system that connect a coach to its Wheels and allows relative motion between them. Maximizing the contact between the wheel & rail. Providing steering stability & supporting the weight of the vehicle. Ensuring the comfort of passenger by absorbing and damping. Function of suspension system:

5. 1. Two stage suspension system: This system has both secondary as well as primary suspension. Comfort level is an important consideration. Pay load is low as compared to tare weight. Moderate high speed is required Types of suspension system use in IR.- There are two types of suspension system use in Railway:- Secondary suspension connects the vehicle body to the bogie frame while primary suspension connects the bogie frame to the axle ICF coache  maximum tare weight 50 Tonnes LHB coache  maximum tare weight approximately 40.3 tonnes

6. This system has either secondary or primary suspension but not both. Most of the single stage suspension designs in existence today have secondary suspension. This system is used in vehicles where: Comfort is not the primary criteria High carrying capacity compared to tare weight. Moderate speed are required. 2. Single stage suspension system:

7. Suspension System in ICF Bogie based on suspension component With steel coil spring With air spring Integral Coach Factory(ICF)

8. Suspension System in FIAT Bogie based on suspension component With steel coil spring With air spring Fabric Italina de Automobil Torino(FIAT)

9. Air suspension SCHEMATIC LAYOUT 60 O R 60 O R 60 O R 60 O R

10. Constructional details of air spring This Air spring is a cylindrically shaped bellow that rolls over a custom contoured pedestal. The Air spring has nine major parts. Air Spring (or Elastomeric Rubber Bellow) Bead Skirt Upper Mounting Plate Bead Ring Pedestal Assembly (or Piston) Emergency Spring Bumper Support Plate Spacer Plate Base Plate

11. Air spring (Elastomeric Rubber Part) The Air Spring is a highly engineered pneumatic cylinder. It is made of elastomeric material and is nearly cylindrical in shape. It contains nylon cords that are laminated with elastomeric rubber and cured together for an airtight seal. At each end of the Air Spring there is a bead wire for reinforcement and sealing purposes. Bead skirt :- The bead skirt is made of aluminium and a bead groove is machined for a precision circumferential fit to assure the bead wire seats properly to seat with the top or upper mounting plate. This aluminium is high grade and more than strong enough to be used in any application, since the air spring carries the load.

12. Upper mounting plate :- Upper mounting plate is made of steel or aluminium. The upper plate is to be placed upon the bead skirt with the elastomeric rubber part bead wire seating in the bead skirt and to be bolted together to form the upper seal. The mounting plate is fitted with an air entrance for inflating the parts to a desired pressure. The air passage is designed such that an orifice could be added to attain additional air damping if so desired. The upper plate, further more, acts as a shield. (to keep foreign material, oil and grease off the rubber part) Bead ring :- The bead ring is also made of aluminium and is located at the bottom of the assembly and serves the same purposes as a bead skirt, and forms the lower seal. The bead ring is bolted to the pedestal.

13. Pedestal assembly (or piston) The pedestal (or piston) serves the purpose, as a component is the lower sealing procedure and support member. This steel part act as a lower mounting surface. The pedestal (piston) is tall enough to let the air spring oscillate with the given load conditions placed upon the spring. Vertical dynamic stiffness is obtained with either a contoured pedestal or a reservoir. Emergency spring The emergency spring (on bumper) provides an auxiliary spring system in the event of an air system failure. It is an integral feature of the air spring assembly and is secured to the upper mounting place with four bolts. It also has a rulon pad bounded to its contact surface to help facilitate lateral motion in the zero pressure condition.

14. Bumper support plate and spacer plate The bumper support plate is a steel plate (with two grooves and a hole in the centre) which goes on top of the spacer plate (with two grooves and No hole in centre). These two plates are bolted to the top of the pedestal assembly with four bolts. The bumper support plate is provided smooth surface for the emergency spring with rulon pad to slide on laterally in the zero pressure condition. Base plate The base plate is a steel plate, which is bolted to the bottom of the pedestal assembly with 6 bolts. This plate has three counter bore holes, which allows for the attachment of the assembly.

15. The levelling valve is fitted with Top bolster and is designed to move up and down along with bolster. Levelling valve :- Under normal condition, it is designed to take LAP position when the actual buffer height is equal to the required buffer height.

16. It also connects the air springs with exhaust to release the excess air from air spring, whenever the bolster goes up due to reduction in the Pay load after detraining of passengers from the coach. It connects the main reservoir with Air spring and admits more air, whenever the bolster comes down due to abnormal increase in the Pay load (Super Dense Crush load). continuation :-

17. It is fitted in between the levelling valve and bottom of the bogie frame. The function of installation lever is to operate the levelling valve automatically by moving the handle of the levelling valve up and down according to the condition of the load. This up and down movement of IL, levelling valve allows the compressed air into the Air spring or releases the air from the air spring through levelling valve in proportion to the pay load of the coach. INSTALLATION LEVER:

18. DETAILS Working of Levelling valve :-

19. DUPLEX VALVE :-

20. It is a double check valve provided between the two Air springs of the same bogie. It operates with a Pressure differential of 1.5 bar. It comprises of two check valves side by side, arranged so that air can flow in either direction whenever the air pressure differential exceeds the pre-set value of 1.5 bar. Whenever a burst of air spring occurs on one side, this valve will ensure that no severe tilt or twist occurs during movement of the coach. Both the check valves of Duplex valve remains closed, if the pressure between the two springs is within 1.5 bars. In case of burst of Air Spring, the air leaks to atmosphere . Due to high pressure differential, the Duplex check valve releases the air from the intact air spring through burst air spring. Thus complete coach will gradually come downed rest on the emergency rubber springs. DUPLEX VALVE :-

21. Isolating cock :- The isolating cocks are provided in the pneumatic suspension system at predetermined locations to stop the air supply in either bogies in the main reservoir for under taking local repairs. The total number of cocks required per coach is 3(three). Non -return valve :- The check valve provided in the system is a non return valve which allows the air to flow unidirectional from feed pipe to main reservoir in the event of failure or breakage in the feed pipe, the check valve will not allow the air to flow off of the pneumatic suspension system and thus keep the system operative for sometime. The total number of check valve required per coach is 1(one).

22. Main Air Reservoir :- The capacity of the main reservoir is 150 litres. It is exclusively used for feeding the compressed air in to the Air Spring. Auxiliary Reservoir :- It is fitted with the Air Spring. The capacity of this reservoir is 20 Litres for DEMU(Diesel Electrical multiple Unit) and 40/60 Litres. For Fiat Bogie. There is an orifice kept between air spring and additional reservoir. It acts as an Air damper to over come vertical and lateral oscillations so as to increase the riding comfort.

23. HANDLING PROCEDURE FOR AIR SPRING

24. continuation :-

25. Install the air spring assembly on the test bench at design height (289-294 mm). While maintaining the design height, gradually increase the air pressure to 6 kg/cm2 and stabilize the pressure for 1-2 minutes. Disconnect/turn off the air supply to the test vane with the help of isolating cock and check the leakage in the air spring assembly with soap solution. Check the pressure drop in the air spring assembly after 15 minutes. The pressure drop in the air spring assembly after 15 minutes should not exceed 1% (0.06 kg/cm2) of the test pressure (6 kg/cm2). The air spring design height should remain within 289-294 mm during the air spring assembly leakage test. Testing of air spring assembly on leakage test bench :-

26. FAILURE INDICATION & BRAKE APPLICATION (FIBA) DEVICE

27. THANK YOU