schedule of technical requirements metal ......emu coaches having icf bogie str no. -...

Ref: CG-WI-4.2.1-1 Ver 1.0

of 37 Date / Month of issue: August, 2020

STR No. RDSO/2008/CG-1, Rev.-1

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Prepared By: V. K. Singh/ SSE/Design

Checked By: Praveen Kumar/DD/VDG

Approved By: Shobhit Pratap Singh /JD/VDG

INDIAN RAILWAYS

SCHEDULE OF TECHNICAL REQUIREMENTS

FOR METAL BONDED CONICAL RUBBER SPRING WITH

EXTERNAL DAMPER FOR PRIMARY SUSPENSION OF EMU COACHES HAVING ICF BOGIE

STR NO. - RDSO/2008/CG-01

Record of Amendments/ Revision:

S. No.

Date / Month of Issue:

Revision / Amendment

Page No Reason for Amendment

1. September, 2010 None - ------

2.

September, 2020 Rev.-1 - As per Amendment slip

Issued by:

CARRIAGE DIRECTORATE

REASEARCH DESIGNS AND STANDARDS ORGANISATION MINISTRY OF RAILWAYS

LUCKNOW -226011

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FOREWORD

This Schedule of Technical Requirements (STR) spells out the schedule of technical requirements of for metal bonded conical rubber with external damper for primary suspension of EMU Coaches having ICF bogies.

The specification shall not be altered /modified or reproduced in any form without

the written permission of the Director General (Carriage), RDSO, Lucknow.

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CONTENTS Description Page

I FOREWORD … … … … … … … 2 II CONICAL SPRING ASSEMBLY (Section -A)

1. Scope 5 2. Operating Conditions 5 3. Environmental Condition 5 4. Scope of Supply 6 5. Procedure for Vendor Registration 6 6. Technical Requirements 12 7. Space Envelope 13 8. Mounting Arrangement 14 9. Submission of Offer 14 10. Guarantee 15 11. Installation, Commissioning, & Maintenance 15 12. Inspection and Testing 16 13. Tolerance 18 14. Minimum required testing equipments 18 15. Marking 18 16. Packing 18 17. Maintenance Manual 18 18. Clarification 18 Annexure – A 20

III TYPE TEST REPORT (Section - B) 1. Requirements 21 2. Testing of Metal Bonded Conical Rubber Spring 22 3. Bonding Strength Test 22 4. Vertical Load vs Deflection Test (Before Endurance Test) 23 5. Shear Load vs Deflection Test (Before Endurance Test) 23 6. Endurance Test 24 7. Vertical Load vs Deflection Test (After Endurance Test) 26 8. Shear Load vs Deflection Test (After Endurance Test) 26 9. Superimposition of Acquired Data 26 10. Creep Test 26 11. General 27 ANNEXURE – I to VII 28 to 34

IV DRAWINGS

1. CG-K6008 35 2. CG-K6007 36 3. CG-K6006 37

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AMENDMENT SLIP

S. No.

Description Clause No.

Page No. of old STR

Reason for Amendment

1 Minor correction in scope of supply.

4.1/ Section - A

5 Minor Correction.

2 Modified para. 5.4.d 5.4.d/ Section-A

7 Minor Correction.

3 Modified para. 5.4.f 5.4.f/ Section-A

7 Minor Correction.

4 Modified para. 5.4.g 5.4.g/ Section-A

7 Reference of ISO document for vendor status upgradation added.

5 Earlier Clause no. 5.5 and 5.6 of Section – A deleted.

5.5 & 5.6 / Section-A

8 Not required in STR. These are make part of vendor registration form.

6 New Clause no. 5.5 in Section – A added.

5.5 / Section-A

------ In view of make in India policy. Conditions for complete indigenous manufacturers added


5.6 / Section-A

------ New clause added.


5.7 / Section-A



5.8 / Section-A


10 Clause no. 6.3.1.b in Section – A deleated.

6.3.1.b/ Section-A

10 Conical spring with these characteristics were failed in service trials.

11 Minor correction in clause 12.3/Section - A

12.3/Section - A

14 Minor Correction.

12 Replace word “bumper”

with “Conical Rubber

Spring” at some places.

3.1, 3.2, 5.0 and 6.1 of

Section - B

19 & 20 Error corrected.

13 Note no. 1 in drawing

no. CG-K6007 deleted.

Drawing No. CG-K6007

32 Minor correction.

14 Modification in fitment arrangement of conical spring is axle box.

Drawing No. CG-K6006

33 As per experience gained during oscillation trials.

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(SECTION – A)

SCHEDULE OF TECHNICAL REQUIREMENTS FOR METAL BONDED CONICAL RUBBER SPRING WITH EXTERNAL DAMPER FOR PRIMARY

SUSPENSION OF EMU COACHES HAVING ICF BOGIES

1.0 SCOPE

This Schedule of Technical requirement covers the necessary requirements relating to the design, suspension characteristics, fitment Arrangement, material, testing procedure and supply of metal bonded conical rubber spring to be provided in the primary stage of existing two axle ICF bogies having pneumatic suspension at secondary level for EMU coaches running on Indian Railways. The scope of supply shall generally be as per clause 4.0 of this schedule of technical requirement (STR). However, if the supplier feels that certain additional items are necessary for the improved working performance of the system, they may be quoted for the same. In any case purchaser will be at liberty to buy all or part material from the offer.

2.0 OPERATING CONDITIONS

2.1 Each coach having two bogies shall be provided with 16 Nos. of metal bonded

conical rubber spring (8 Nos. per bogie) between the bogie frame and axle box which will act as a primary suspension system.

2.2 Each metal bonded conical rubber spring is subjected to variable, heavy duty

dynamic loading in vertical, lateral and longitudinal direction during running. The Dynamic loading is of sinusoidal in nature.

2.3 The coach fitted with metal bonded rubber spring would be having a maximum

operating speed of 110 kmph for EMUs and shall negotiate curves up to a minimum radius of 175 meter.

2.4 Track ballast during train operation may occasionally hit metal bonded conical

rubber spring assembly. 3.0 ENVIRONMENTAL CONDITIONS: 3.1 The metal bonded conical rubber spring shall normally be subjected to following

environmental conditions: Maximum temperature under sun 600C Ambient temperature 00 C to 450 C in shade Average relative humidity 70% to 90%, 100% on several days

Rail fall Fairly heavy maximum being 200 mm in 24 hrs., typical to coastal area.

Atmosphere Dusty for several months of year.

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3.2. The metal bonded rubber spring assembly system may also come in contact with

the following during coach maintenance.

a. Chemical product ( like cleaning, compound of coach cleaning ) b. Cotton waste smeared with oil and paint etc. c. Disinfectants d. Oil and lubricant used in the coach bodies.

4.0 SCOPE OF SUPPLY The scope of supply covers the following items: 4.1 For one coach set metal bonded rubber spring with external damper:

SNo. Item Qty.

1. Top Plate 16

2. Conical rubber spring including stud 16

3. Bottom fasteners for fixing with base

3.1 Hex. nut M42 16

3.2 Hex. lock nut M42 16

3.3 Disc Lock Washer 16

4. Top fasteners for fixing conical spring top with bogie frame

4.1 Hex. head bolt M16 X 100 64

4.2 Self locking nut M16 64

4.3 Plain washer for M 16 nut 64

5. Compensating ring 4 mm thick (OD 110 mm / ID 46mm). 32 for TC 80 for MC

6. Wheel Wear Packing ring 20 mm thick (OD 110 mm / ID 46mm)

32

7. Double acting external hydraulic damper. 8

8. Hex. Head bolt M16 X 90 and plain washer for fixing vertical damper.

32

9. Metal collar for mounting metal bonded conical spring on axle box housing.

16

4.2 Any other item, which in the view of supplier is considered essential for operation

or enhances the performance of system, may also be offered. 5.0 PROCEDURE FOR VENDOR REGISTRATION: 5.1 Venders willing to supply metal bonded conical rubber spring assembly for the use

on Indian Railway shall register themselves with Research Design and Standard organization, Ministry of Railway, Manak Nagar, Lucknow – 226011 (RDSO) and should be ISO approved.

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5.2 The venders shall have adequate facilities for the manufacture and testing of metal bonded conical rubber spring assembly conforming to drawings approved by RDSO.

5.3 The venders shall have a well-documented “Internal Quality Assurance System” to

ensure sustained quality of product being manufactured. The Quality Assurance System shall generally cover the following:

5.3.1 System to ensure that correct raw material is being used. The type of rubber used

for the conical spring shall be specified by the OEM. 5.3.2 System ensured that components having manufacturing defects are identified and

destroyed so that such components are not used during assembly of metal bonded conical rubber spring.

5.3.3 System to maintain strict control of dimension and workmanship of component and

assembly product. 5.3.4 System to test and establish that the metal bonded conical rubber spring assembly

manufactured by the firm meets all the requirements laid down in STR/Drawings. 5.3.5 System of periodical calibration of equipments/gauges to ensure accuracy of

product. 5.3.6 System to ensure cleaning and removal of dust/rust and moisture by dry air. 5.3.7 System to ensure metal bonded conical rubber spring assembly is properly packed

to meet the requirements of clause 16 of this STR. 5.3.8 System to ensure traceability at least up to guarantee period. 5.4 Conditions for manufacturers, having MOU with any established OEM:

a) Metal bonded conical spring vendors shall be recognized on the basis of the OEM design. An OEM for this purpose shall be defined as a company having the facilities for designing the metal bonded conical spring and the necessary infrastructure to carry out detailed type tests at their own facility. Their metal bonded conical rubber spring designs should have been approved over other railway systems and been in regular passenger service.

b) Application for registration shall therefore be considered from OEMs or from

companies entering into a valid MOU/Agreement with OEM metal bonded conical spring manufacturers as defined above. The MOU should clearly state that the OEM undertakes to fulfill the warranty and support obligations with respect to technology up gradations as and when required for the metal bonded conical spring, even in case the MOU is rescinded at some later stage.

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c) Since metal bonded conical springs are a safety related suspension element, in-service trials shall be necessary for each OEM design before full clearance is given for supply.

d) OEMs whose metal bonded conical springs have completed five years

satisfactory service on other Railway Systems on at least two hundred fifty coach sets shall only be considered. Vendors shall be required to submit verifiable documentary proof of satisfactory performance of the same. The metal bonded conical springs of a particular design shall be subjected to in-service trials on a minimum of ten coach sets for one year on IR’s system. For this purpose, trial order for minimum ten coach sets shall be given to such vendors.

e) In case of any failure during service trials attributable to poor design or material,

the service trials shall be repeated. RDSO shall decide the cause of failure after investigation in this regard.

f) After completion of service trial period, sample (02 nos) of the metal bonded conical spring shall be subjected to the tests laid down at paras 4.0/Section-B, 12.3/Section-A and 12.4/Section-A. In case the values obtained during these tests are beyond permissible limits, the conical spring design shall be deemed to have failed the service trials.

g) Vendors providing a particular OEM design as defined at (a) above shall be provided part-II status on successful completion of service trials as defined above. A Vendor shall be considered eligible for upgradation to Part-I status on completing successful supply of a minimum of 100 coach sets of the particular type of air spring and also after a minimum period of 18 months after issue of first Inspection Certificate as a Part-II vendor. “Developmental” status on successful completion of service trials on a minimum of ten coach set conical springs for one year from date of commissioning. A Vendor shall be considered eligible for up-gradation as “Approved Vendor” for conical spring on completing successful supply of a minimum of 100 coach sets of conical springs along with the fulfillment of conditions mention in latest apex ISO document of RDSO for “Vendor- Changes in approved status” (document no. QO-D-8.1-11 )

h) In case any part of the metal bonded conical spring assembly is manufactured

outside India, a certificate of country of origin shall be provided with initial supply clearly establishing the source of manufacture. Source of manufacture of each component shall be provided by the vendor at the time of design approval.

i) After type tests, of a particular OEM design are will be approved by RDSO.

Vendors shall ensure that metal bonded conical spring to the particular specification are supplied with components manufactured from the sources as indicated at the time of design approval and used for type testing.

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j) In case design of conical spring assembly is changed, fresh type tests and service trials shall be necessary. However service trials can be dispensed with by RDSO considering the reasons for change and extent of modification.

k) In case, source of any component of metal bonded conical spring is changed or

any additional new source is introduced, fresh type tests shall be required. The OEM/vendor should provide the detail information of the source changed/ additional source introduced along with the documentary evidences for the record of this office. OEM shall validate the source in all respects i.e. material, manufacturing process, quality control and inspection & testing etc. to conform to originally approved design and process. Compliance to all obligations including guarantee/warrantee (As per Para 10) shall remain the responsibility of OEM.

5.5 UNDERTAKING FOR INFRINGMENT OF IPR: Vendors should submit undertaking on “INFRINGMENT OF PATENT RIGHTS”.

The undertaking can be as under: Indian Railways shall not be responsible for infringement of patent rights arising

due to similarity in design, manufacturing process, use of similar component in the design and development of this item and any other factor not mentioned herein which may cause such a dispute. The entire responsibility to settle any such disputes/matters lies with the manufacturer/supplier. Details / design / documents given by them are not infringing any IPR and they are responsible in absolute and full measure instead of railways for any such violations. Data specifications and other IP as generated out of interaction with railways shall not be unilateral used without the consent of RDSO and right of Railways / RDSO on such IP is acceptable to them.

5.6 DECLARATION OF CONFIDENTIALITY OF SUBMITTED DOCUMENTS: While submitting a new proposal/design, vendors must classify their documents

confidentiality declaration, such as, “This document and its contents are the property of M/s XYZ (Name of vendor) or its subsidiaries. This document contains confidential proprietary information. The reproduction /distribution/ utilization or the communication of this document or any part thereof, without express authorization is strictly prohibited. Offenders will be held liable for the payment of damages. Indian Railways / RDSO is granted right to use, copy and distributes this documents for the use of inspection, operation, maintenance and repairs etc”.

5.5 Conditions for complete indigenous manufacturers without MOU with any established OEM:

a) Supplier should have in-house facilities as per STR i.e. design, manufacture

and Type testing of Conical Spring. Facilities available and type testing shall

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be witnessed / verified by RDSO officials right from the stage of fitment on

machines and intermittently as decided by RDSO till completion.

Manufacturing of some components may be done at reputed

sister/allied/outsourced concern with approval of RDSO.

b) After complete type testing of conical spring followed by satisfactory test

results, firm will supply 10 coach set conical springs only to IR for service

trials, which shall be fitted in coaches where passenger occupancy is relatively

lesser.

c) Field performance of these 10 coach set conical springs shall be monitored for

six months and after six months of service, 08 conical springs of one bogie

subjected to the tests laid down at paras 12.2/Section-A and 12.3/Section-A.

d) If results of above tests are found within specified limit then firm shall be

considered for supply of 25 coach set conical springs only to IR and again

performance of these conical springs shall be monitored in field for one year

from date of commissioning.

e) In case of any failure during service trials attributable to poor design

/quality/material, the service trials of that particular type of conical spring may

be repeated with upgraded design or material.

f) After successful trial reports from Zonal Railways followed by satisfactory

characteristic testing results of two nos. sample in-service conical springs at

firm’s premises as per para. 12.3/Section-A and 12.4/Section-A of this STR,

vendor shall be allowed for regular supply of conical springs as a

developmental vendor.

g) A Vendor shall be considered eligible for up-gradation as “Approved Vendor”

for particular type of conical spring on completing successful supply of a

minimum of 100 coach sets of conical spring along with the fulfillment of

conditions mention in latest apex ISO document of RDSO for “Vendor-

Changes in approved status” (document no. QO-D-8.1-11 )

h) Source of manufacture of each component of conical spring shall be provided

by the vendor at the time of design approval.

i) After type tests, a particular vendor design will be approved by RDSO,

vendors shall ensure that metal bonded conical spring are supplied with

components manufactured from the sources as indicated at the time of design

approval and used for type testing.

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j) In case design of conical spring assembly is changed, fresh type tests and

service trials shall be necessary. However service trials can be dispensed with

by RDSO considering the reasons for change and extent of modification.

k) In case, source of any component of metal bonded conical spring is changed

or any additional new source is introduced, fresh type tests shall be required.

The OEM/vendor should provide the detail information of the source changed/

additional source introduced along with the documentary evidences for the

record of this office. OEM shall validate the source in all respects i.e. material,

manufacturing process, quality control and inspection & testing etc. to conform

to originally approved design and process. Compliance to all obligations

including guarantee/warrantee (As per Para 10) shall remain the responsibility

of OEM.

5.6 Capability and capacity assessment of vendors:

Verification of STR and QAP along with assessment of capacity and capability of manufacturer of Metal Bonded Conical Spring shall be undertaken by authorized representative of RDSO at the premises of firm. In case of the firm having their sub assembly manufacturers located at different locations, the facilities at the location of manufacturing sub components will be verified along with witnessing of assembly of conical spring and Type Testing of Conical spring.

5.7 Prototype Inspection:

5.7.1 Vendor shall offer at least two nos. prototype conical springs, for necessary inspection and testing as per paras. 12.2/Section-A, 12.3/Section-A and 12.4/Section-A of this STR.

5.7.2 The prototype inspection of conical spring assemblies shall be carried out by

Carriage Directorate of RDSO or their nominee at manufacturing premises of firm. The manufacturer shall provides material, tool and any other assistance without any extra charges which may consider necessary for any test / examination and dimensional test.

5.8 Service trials quantity: As per the requirement of Indian Railways, RDSO at its discretion with approval of competent authority can increase the trial quantity of conical springs of particular vendor based on the satisfactory performance of conical springs supplied earlier against developmental orders for service trials.

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6.0 TECHNICAL REQUIREMENTS: 6.1 Axle Guidance:

The Metal bonded conical rubber springs are required to provide rigid guidance to the wheel/ Axle set with respect to bogie frame, by providing optimized stiffness characteristics in vertical, lateral and longitudinal directions. Compression and shearing of metal bonded rubber is permitted only in the vertical mode however pure rubber compression is desirable in lateral and longitudinal directions.

6.2 Load Conditions :

The load condition for each metal bonded conical rubber spring is given as under: 6.2.1 Static Vertical load:

S.No. Load EMU

1. Tare Load 17.5 kN

2. Normal Load 30.0 kN

3. Gross Load 42.5 kN

6.2.2 Lateral and Longitudinal Load:

S.No. Load EMU

1. Maximum Shear Load 16.20 kN

6.3 Stiffness and Damping Characteristics:

The conical rubber spring being circular in nature, generally provides similar lateral and longitudinal characteristics. The stiffness characteristics for both the above mentioned options are given as under:

6.3.1 Stiffness Characteristic 6.3.1.a The differential stiffness characteristics of conical rubber spring in lateral and

longitudinal directions are given as under:

S.No. Fz (KN) Vertical Stiffness

(N/mm) Lateral stiffness

(N/mm)

Longitudinal Stiffness (N/mm)

1. 17.5 700 + 100 2000 + 300 1650 + 250

2 30.0 850 + 125 2800 + 400 2330 + 350

3. 42.5 1075 + 150 4950 + 700 3150 + 470

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6.3.1.b The stiffness characteristics for conical rubber springs with similar lateral and longitudinal characteristics are given as under:

S.No Fz (KN) Vertical Stiffness

(N/mm) Lateral/ Longitudinal

Stiffness (N/mm)

1. 17.5 750 + 100 2000 + 300

2. 30.0 700 + 100 2250 + 300

3. 42.5 760 + 100 3000 + 450

6.3.2. Damping Characteristics:

The double acting external Hydraulic damper is provided between bogie frame and axle box which is located centrally near the axle box. The damping contributes to the metal bonded conical rubber spring located on the same axle box. The rating and details of external damper is given as under.

S.N. Description EMU

1. (i) Full Extended Length (ii) Nominal fitment distance

407 mm. 370 mm.

2. Damping capacity 1500 - 2000 N/0.1m/sec.

3. Stroke length + 60 mm

4. Working frequency 0.1Hz to 11.0 Hz

5. Max. Dia. Of Damper Barrel 82 mm

6. Orientation of Fastening Bolts Vertical

7. Cross section diameter of eye at mount hinge of damper

17 mm

The manufacturer is required to furnish the characteristics details of external Hydraulic Damper as per RDSO specification No. C–8703 Rev.2.

6.4. Operating Frequency and Amplitude: 6.4.1 For all the vertical load conditions as given in para 6.2, the operating vertical

frequency varies from 0Hz to 11 Hz with an average amplitude of oscillation as +10 mm.

6.4.2 The isolating vertical frequency shall be more than 11.0 Hz with a maximum loss

angle as 60 at a vertical displace of + 5 mm. 6.4.3 The Metal bonded conical rubber spring system shall be designed suitably to

dissipate heat energy developed within rubber element. 7.0 Space Envelope A generalized space available for the existing primary suspension in ICF bogie is

given as per RDSO drawing No. CG K–6008 for EMU/DMU coaches. However, due to unique end fastening arrangement of metal bonded conical rubber spring

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the tailored shape and space enveloped for the metal bonded conical rubber spring including lower end stud shall be as per RDSO drawing No. CG – K 6006.

8.0 Mounting Arrangement: 8.1 The Mounting arrangement of metal bonded conical rubber spring under tare

condition for the motor/trailer coach bogie shall be as per RDSO Drg. No. CG-K6007 Alt. c for EMU/DMU coaches.

8.2 The thickness of spacer plate for the motor and trailer coach bogie shall depend

upon the vertical stiffness of conical rubber spring. 8.3 Under tare condition vertical load on each conical rubber spring for Trailer and

Motor Coach bogie are 17.28 KN and 27.87 KN respectively. 8.4 The lower end fastening arrangement and details of top plate are shown is

enclosed Drg. No. CG – K 6006 Alt. a and CG-K6007 Alt. c. 9.0 SUBMISSION OF OFFER 9.1 Firms desirous of submitting their initial offer to Indian Railway for seeking

developmental approval from RDSO for supply of material as per this STR shall submit their proposal accompanied by documents containing the following information to Director General, RDSO, Ministry of Railways Manak, Nagar, Lucknow – 226011.

1. The type test of the proposed metal bonded conical rubber spring based on this

STR. 2. Dimensional drawing of metal bonded conical rubber spring. 3. Weight of one metal bonded conical rubber spring assembly. 4. Whether proposed conical rubber spring is being used by any other rail- road

system? If yes, details regarding quantity, type of stock, maximum operating speed, type of service, average annual running kilometers, life cycle obtained by the user rail – road maintenance cycle followed by them shall be furnished.

5. Details of deviation from the STR. 6. Contents of Indigenous and imported items in the offered metal bonded conical

rubber spring. 7. Expected operating life of metal bonded conical rubber spring in terms of time or

distance.

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8. Authorization certificate /Licenses etc. from the original manufacturer permitting manufacturer and assembly of the offered rubber spring (for proposal from other than the original manufacturer).

9. A write up giving broadly the maintenance requirements on time / distance basis

along with the facilities that would be needed for proper maintenance /up keep of offered conical rubber spring assembly.

10. A detailed write up giving the details of “Quality Assurance System” being

followed for manufacturer of the offered items. 11. Details of manufacturing and testing facilities available with the firm.

9.2 The information as received above shall be used for preliminary evaluation of the

firm’s capability in meeting with the requirements of this STR. 9.3 The firm shall be required to submit a Type Test Report of a proposed design after

the preliminary evaluation carried out as per para 9.2 is found satisfactory. Type test report shall be complying with Annexure “A” of this STR.

9.4 The premises of the firm may also be visited by RDSO officials for on the spot

assessment of the firm’s capacity cum capability, manufacturing and testing facilities after the type test report is accepted by RDSO.

9.5 RDSO reserves the right for granting approval or otherwise to a firm. 10.0 GUARANTEE

The complete metal bonded conical rubber spring including accessories shall be guaranteed for satisfactory performance for a minimum period of 60 months from the date of actual commission in the bogie or 72 months from the date of supply. Satisfactory performance for this purpose means that complete metal bonded conical rubber spring assembly or any of its part shall neither show any kind of deterioration which is likely to render it unserviceable nor lose its characteristics as stipulated in this STR. During the guarantee period for reasons attributable to manufacturing /design defects. In the event of “Non satisfactory Performance” of any of the items as indicated above, supplier will have to replace the same at his own expenses without levying any cost involved in transportations handling and replacement of such item on the purchase.

11.0 INSTALLATION COMMISSIONING AND MAINTENANCE:

On placement of order, supplier whose equipment will be purchased for the first time for installation on the coaches, shall have to be depute his representative at his own expenses to associates with the purchaser in installation and

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commissioning of the equipment on the first five coaches. He shall also depute his representative during maintenance schedule undertaken on his equipment as per maintenance book let supplied by him.

With the every order for supply of the metal bonded conical rubber spring assembly, the supplier shall have to supply maintenance instructions in the form of two booklet (Hard Copy) and one copy on compact disc. (MS-Office Compatible) Maintenance book let supplied by the supplier shall cover the following aspect in details. 1) Specification of Metal bonded conical rubber spring. 2) Working principle based upon the actual construction. 3) Constructed details giving sketch, drawing and photo copy etc. identification

various items and their part number etc. for easy identification.

4) Procedure for dismantling using sequential steps with the help of sketch etc.

5) Procedure for assembly, using sequential step with the help of Sketch etc.

6) Jigs, tool, other material and details of special set ups etc., necessary for item 4 and 5 above.

7) Testing procedure and facility, required along with their details.

8) Comprehensive details containing legible sectional view of defects normally obstruct or may happen on metal bonded conical rubber spring with clear remarks, whether the defects is rejectable or non rejectable.

9) List of other defects and their remedies.

10) Periodicity for various maintenance activities on time and distance basis.

11) Do’s and don’ts for maintenance officials. 12.0 INSPECTION AND TESTING 12.1 General Requirements:

During initial approval of a firm by RDSO and latter on when approval has been granted, RDSO for the purpose of ensuring quality of purchased product may carry out periodic quality Audit, inspection and testing of the equipment at the premises of the manufacturer. Purchase inspection shall be done at the premises of the manufacturer by a representative of Research Designs and Standards

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Organization or an agency authorized by RDSO. The supplier shall have to arrange for the following and associate with the same. 1) Access to all records considered relevant for such activity by inspecting official. 2) Questioning of relevant personal engaged in production, testing and quality

checking activity etc. or related issue. 3) Testing of few samples of items already produced by the firm to ascertain the

technical characteristics given in this STR. 4) Any other check considered necessary by the inspecting party.

12.2 Dimensional Check:

S. No. Item Reference Document

1 Top plate dimension, Hole spacing and hole size.

As per approved drawing of firm.

2 Metal Collar/ Adapter ring dimensions

3 M42 stud size

4 Packing plate dimension

5 Details dimension of bottom fitment arrangement

12.3 Tare Load height Check:

In this test the metal bonded conical rubber spring is subjected to a vertical load of 17.5 KN and the overall height of the spring is measured from the bottom seat, which should be 318 + 2 mm.

12.4 Characteristics Test: The Characteristics tests of metal bonded conical rubber shall be submitted by the supplier in the form of a type test report containing all test parameters as given in para 3.0 to 8.0 of Section – B however, the inspecting official can ask for some sample tests which are to be complied by the firm supplying the metal bonded conical rubber spring. Vertical load vs. deflection characteristics measured at vertical loads on conical spring given in type test report / QAP approved by RDSO.

12.5 Sample Checks:

10% samples of the lot or a minimum 10 samples shall be picked up randomly for dimensional & other specified inspections as given in clause 12.2 of this STR.For other specified inspections a given in clause 12.3 and 12.4 of this STR, samples shall be picked up randomly as under:

Lot size upto 10 25 50 75 100

No of samples 2 3 4 5 6

For lot sizes more than 100, 5 % of the samples shall be picked up randomly for the above inspections.

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In case any picked up sample fails, manufacturer/supplier shall re offer, rectifying the defects. However, in such cases double the quantity of samples shall be picked up and shall be checked for dimension and other specified testings. In case any one sample again fails the entire lot shall be rejected.

13.0 Tolerance : Tolerance in dimensions should be as per IS 2102 (Part -I) and in physical

characteristic as per Annexure- C of BS EN 13913:2003. 14.0 Minimum required testing eq./gauges at vendor premises for inspection :

a. Universal testing machine equipped with precise gauges for load deflection

test. b. Vernier calipers capable to measuring all dimensions of conical spring. c. Other necessary gauges to carry out dimensional tests.

15.0 Marking:

Every Item of metal bonded conical rubber spring shall be legibly marked by using suitable means to indicate the following:

a) Manufacturer’s initials. b) Month and year of the manufacturer. c) Identification marks i.e. part, number, batch number etc.

16.0 Packing :

The metal bonded conical rubber spring assembly shall be suitably packed along with its loose parts, exposed threaded portion, to protect against any damage that may be occurred during transit and handling. Any hole which may contaminate dust shall be suitably covered with plastic or rubber cap.

17.0 Maintenance Manual

The supplier shall provide at least one copy free of cost for each consignment, a detailed maintenance manual for maintenance and overhaul purpose

18.0 Clarification

18.1 RDSO may draw samples for quality check to test any property mentioned in this specification at it’s discretion. The vendor shall arrange testing of these samples at a reputed outside laboratory as decided between RDSO and the vendor. The testing charges should be borne by the vendor.

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18.2 Additional information if required may be obtained from the office of the Director General (Carriage), RDSO, Manak Nagar, Lucknow – 226011.

Ref: CG-WI-4.2.1-1 Ver 1.0



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Annexure – A

REQUIREMENTS OF TYPE TEST REPORT

The type test report of metal bonded conical spring shall consist of the following, clearly represented by graphs/ Hysterisis loop as well as in tabulation forms, with detailed test procedures and their results: - 1) Lateral characteristics measurement at 17.5, 30.0 & 42.5 KN vertical loads, lateral

stroke dy = ±2 and ±5mm, speed V= 5 mm/sec at 0.1 Hz frequency.

2) Vertical characteristics measurement at 17.5, 30 & 42.5 KN vertical loads with vertical stroke dz = ±7.5, ±10 and ±15mm, speed V= 5 mm/sec at 0.1 Hz frequency.

3) Physical tests of rubber for metal bonded conical spring.

(i) Abrasion test as per para. 7.2.7 of EN 13913 : 2003 (E).

(ii) Resistance to “Oil and Petroleum Product” as per para. 7.2.5 of EN 13913: 2003 (E).

(iii) Accelerated ageing test as per para. 1.1.1/ ii /Section-B of this STR. (iv) Resistant to ozone test as per para. 7.2.4 of EN 13913 : 2003 (E). (v) Fire behavior test as per para. 7.2.8 of EN 13913 : 2003 (E). (vi) Resistance to chemical product test as per para. 7.2.6 of EN 13913 : 2003 (E)

4) Load versus deflection characteristics (before and after endurance test) of metal bonded conical spring in vertical and lateral mode as per paras 4.0/Section-B and 5.0/Section-B of this STR.

5) Endurance test of metal bonded conical spring alongwith vertical and lateral

characteristics for minimum 1 million cycles, as per para 6.1/Section-B and 6.2/Section-B of this STR.

6) Bonding strength test as per para 3.0/Section-B of this STR.

7) Physical properties test of rubber material as per para 1.1.1/ i /Section-B of this STR.

8) Material test report (supported by standard test specifications). 9) Any other test felt necessary by the manufacturer.

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(SECTION – B)

Tests in Type Test Report

1.0 REQUIREMENTS: 1.1 MATERIAL 1.1.1 Rubber The rubber element in the metal bonded conical rubber spring should be

manufactured from natural rubber compounded to conform to the requirements stipulated in this STR. The rubber compound shall conform to the following stipulations.

a. The ash content shall not exceed 8% and shall be checked on as per method specified in IS : 3400 (Part 22).

b. The specified gravity shall not exceed 1.22 and shall be checked as per method specified in IS : 3400 ( Part IX).

(i) Physical Properties of Rubber Compound:

The physical properties of rubber compound should be checked as per method

given in IS specification mention below and shall conform to the following limits.

S.No. Properties Method /Standards Permissible limits

1. Tensile strength ( Kg/Cm2 ), Min

IS: 3400(PART –I) 210

2. Elongation at Break ( % ) min.

IS: 3400 (PART –I) 450

3. Compression set ( %) at 70+ 10 c for 24+0/-2 Hrs., Max.

IS: 3400 (PART –X) 20

4. Hardness (Shore ‘A’) IS: 3400 (PART –II) 50-60

(ii) Accelerated Ageing:

a. The manufacturer shall carry out the accelerated ageing test on the test pieces prepared from the same rubber compound as stated in para 11.a/Section-B. The method of accelerated ageing test shall be in IS: 3400 (part–IV) to check the accelerated ageing properties of the rubber compound and their conformance with permissible limits.

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b. After ageing at 70 + 100 C in on air oven for 72 hours, the hardness, tensile strength, and elongation at break shall not vary from the values obtained with an un-aged specimen by more than the limits given below:

S No. Properties Permissible limit

1. Hardness (Shore ‘A’) +7 - 0

2. Tensile strength +/- 20%

3. Elongation at break ( %) + 5% - 20%

1.1.2 Steel:

a) The end mounting plate, inter leafs and other metal parts shall be of steel confirming to IS :2062 Gr. Fe 410 Cu WB or stainless steel.

b) In the preparation process of metal plates, end fasteners or interleaf it shall be ensured that all sharp edges and burrs are removed and they are chemically treated and cleaned before. Shot grit blast as per IS : 9139-GM30.

Bonding of Metal to Rubber:

a) Before applying primer coat for achieving the required bond strength between metal part and rubber, the metal parts, which are ready for use, should be stored suitably to avoid contamination on the surface.

b) The process and bonding agent adopted for bonding of rubber to metal plates shall be of proven quality. “Chemlok” as bonding agent is recommended.

c) The temperature and moulding time shall be optimized for proper curing of rubber. The optimization should be done by using a Rheometer.

d) The rubber should be smooth and free from pinholes, blister and other visual flaws. 2.0 Testing of metal bonded conical Rubber Spring:

The metal bonded conical rubber spring unit comprising of bonded metal interleaf/ cones shall be subjected to following tests independently. a) Bonding strength test. b) Vertical load Vs deflection test. (Before and after endurance test) c) Shear load Vs deflection test. (Before and after endurance test) d) Endurance test (vertical & lateral) e) Creep test.

Test (b) and test (c) are required to be conducted before and after test (d)

3.0 Bonding strength test :

The objective of this test is to determine bond strength between metal plate and rubber, under pre-determined load or deflection. This test is conducted as per IS : 3400 (Part – XIV) . The bond should be capable of bearing a minimum stress level of 35 Kg/Cm2. This test shall be conducted before test 4.0 (b) and test 4.0 (c).

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3.1 Vertical bonding test:

In this test a compressive vertical load, which is 200% of maximum static load, is applied on the conical spring for duration not more than 60 seconds. OR The conical spring should be subjected to 35 mm vertical deflection under compression for duration not more than 60 seconds. At the end of test there should not be any visible slip between metal and rubber or crack on the rubber surface.

3.2 Shear bonding test :

In this test a compressive vertical load which is 150% of maximum static load is applied on the conical spring and then a shear load of 32.4 KN is applied at the top most plate for duration not more than 60 seconds after rigidly supporting the bottom seating end. At the end of the test there should not be any visible slip between metal and rubber or cracks on the rubber surface.

4.0 Vertical load vs deflection test: (Before Endurance test)

The conical rubber spring should be subjected to three successive load cycles up to 150% of gross static vertical load at quasi-static frequency of 0.1Hz for pre conditioning. In the fourth cycle the conical rubber spring shall be compressed with a load of 0.10 KN and the deflection taken as zero at this point. The fourth cycle is completed to record force Vs deflection curve in the form of hysterisis loop for a deflection range as obtained during initial three load cycle (loading and unloading). The load and deflection values shall be recorded digitally and the values shall be provided in the form of X – Y plot and table (Ref. Annexure-I). The following geometric parameter shall be recorded:

SNo. Parameters Before Endurance Test

After Endurance Test *

1. Free height (mm)

2. Outer dia (mm)

3. Vertical axis orientation

5.0 Shear load vs deflection test: (before endurance test)

In this test the M 42 at seating location for metal bonded conical rubber spring is rigidly clamped to a fixed horizontal plate and shear load is applied at the top of spring to measure the shear load Vs shear displacement characteristics. The maximum lateral load shall be 150% of maximum shear load which shall be applied in both directions (Positive and Negative) from the mean position at a quasi-static frequency of 0.1 Hz. The pre-conditioning of conical rubber spring is done by giving three successive lateral load cycles and in the fourth cycle measurements are taken for applied shear load and corresponding shear

Ref: CG-WI-4.2.1-1 Ver 1.0



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displacement of conical spring. The above test is conducted under following pre-vertical loads. a) Tare vertical load. b) Gross vertical load c) 150% of gross vertical load

The measurements shall be done using digital methods and the measured data shall be provided in the form of hysterisis loop and tables (Ref. Annexure-II). The following geometric parameters shall be recorded

S.No. Parameters Before Endurance

Test

After the Endurance Test *

1. Free height (mm)

2. Outer dia (mm)

3. Vertical Axis orientation (mm)

In case of those metal bonded conical springs which are having different lateral and longitudinal stiffness characteristics the above shear load Vs deflection test shall be conducted in longitudinal direction which is having a lower stiffness value.

6.0 Endurance test

a) The Endurance test is conducted to assess suitability of the conical rubber spring for use at primary level in conjunction with air spring provided at secondary stage suspension in coach bogie by simulating service conditions in the laboratory.

b) The test on conical spring shall be conducted only when the results of load deflection characteristics are obtained and found satisfactory.

c) The test shall be conducted in vertical and shear modes. d) In case of such metal bonded conical springs, which are having different

lateral and longitudinal stiffness, the shear endurance test shall be conducted in longitudinal direction.

6.1 Vertical Endurance Test

a) The rubber spring is subjected to a pre compressive load, which is 125% higher than the gross static load on a endurance testing machine. This load is taken as datum and further tests are conducted in load control mode.

b) With load datum as given in para (a) above, the plunger is made to oscillate vertically in sinusoidal manner at a frequency of 4.0Hz, such that the maximum compressive load on the plunger does not exceed 150% of the gross vertical load.

c) Endurance test shall be conducted for a total 1 million cycles at a stretch with conditions as stipulated in para (a) and (b) above.

d) During endurance test of 1 million cycle if the temperature build up in rubber conical spring exceeds 70C with respect to the ambient air

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temperature in the surroundings, the oscillating frequency of the plunger can be reduced by 1.0Hz.

e) At the end of every 0.2 million cycles following parameters are required to be measured (Ref. Annexure III)

i) Hystersis loop for 5 successive cycle of vertical load Vs deflection record.(After every 0.2 million cycle of endurance test

ii) Actuator plunger frequency. iii) Conical Rubber Spring temperature rise. iv) Ambient/room temperature.

f) At the end of 1 million cycles following measurements/observations shall be

recorded after 30 minutes from load release.

S.No. Parameters Results

1. Adhesion of bond.

2. Obvious signs of failures.

3. Excessive wear or Abrasions

4. Free height

5. Permanent set.

6.2 Shear endurance test:

a) The M42 steel stud at its seating locations is clamped rigidly on a fixed horizontal table and the spring is subjected to a vertical pre compressive load which is equal to gross vertical load, acting at the geometric centre of top plate. The test is conducted in load control mode and a horizontal force with sinusoidal frequency of 3.0Hz having peak load value as + 150% of maximum shear load is applied simultaneously for 1 million cycles.

b) During endurance test of 1 million cycle as per para (a) above, if the temperature build up in the rubber spring exceeds 7o C with respect to the ambient air temperature in the surroundings the horizontal Oscillating frequency of the plunger can be reduced by 1.0 Hz.

c) At the end of every 0.2 million horizontal oscillating cycles of the actuator plunger following parameters are required to be measured (Ref. Annexure IV).

I. Hystersis loop for 5 successive cycle of horizontal load Vs horizontal

displacement record.(After every 0.2 million cycle of endurance test II. Actuator plunger frequency.

III. Conical Rubber Spring temperature rise. IV. Ambient/room temperature.

At the end of 1 million horizontal cycle, following measurement /observations shall be recorded after 30 minutes from vertical and lateral load release.

S.No. Parameters Results

1. Adhesion of bond.

2. Obvious signs of failures.

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3. Excessive wear or Abrasions

4. Free height

5. Permanent set.

7.0 Vertical load Vs deflection test.( after endurance test )

This Test is required to be conducted after satisfactory Endurance test and shall be carried out on the similar line as given in para 4.0/Section-B.

8.0 Shear load Vs deflection test( after endurance test).

The test is required to be conducted after satisfactory shear Endurance Test and shall be carried out on the similar lines given in para 5.0/Section-B.

9.0 Superimposition of acquired data:

The following data obtained before and after Endurance Test shall be superimposed over each other as details given below:

9.1 Vertical Load Vs Deflection test data

The object is to determine the loss in vertical properties/characteristics of rubber due to endurance test. The characteristics test obtained vide para 4.0 and 7.0 shall be superimposed over each other in the form of hysterisis loop and comparative table (Ref. Annexure V).

9.2 Shear load Vs deflection test data

The object is to determine the loss in shear properties/characteristics of rubber due to shear endurance test. The characteristic data obtained vide para 5.0 and 8.0 shall be superimposed over each other of hysterisis loop and comparative table (Ref. Annexure VI).

10.0 Creep test

The Creep Test is conducted on the metal bonded conical emergency rubber spring by applying a predetermined maximum vertical load, which is born by the spring for a sufficiently long period to determine the magnitude of permanent set or loss in free height under the influence of load with respect to time. The predetermined maximum vertical load which is 150% of gross static load should be applied continuously for a period not less than 30 days. The following measurements are required to be taken.

1. Magnitude of applied vertical load.

2. Free height of rubber spring (before and after creep test)

3. Height of conical rubber spring with respect to time. The height of the spring should be measured after every 24 hrs for the first 15 days and after every 48 hrs. thereafter.

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The vertical deflection Vs time curve should be drawn for the minimum period of 30 days. It can then be extrapolated depending on the expected working age of conical rubber spring (Ref. Annexure VII).

11.0 General :

a) All the tests mentioned in this specification shall be conducted on the same

specimen of conical rubber spring. b) All measurements shall be given in SI units. c) Lay out drawing of jigs and fixtures used in evaluating test parameters shall

be provided in the report. d) The test results shall be furnished by vendor in the form of a type test

report. e) Digital photographs/ pictures of test rig should be provided by contractor. f) A list of instruments used in taking the measurements shall be supplied by

the vendors. g) Any other relevant details in support of accuracy of test shall be given in

type test report.

Ref: CG-WI-4.2.1-1 Ver 1.0



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schedule of technical requirements metal ......emu coaches having icf bogie str no. -...

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