The document describes the development of a Stainless Steel Electrical Multiple Unit (EMU) by BEML for Indian Railways. Key points: 1) Existing EMUs were prone to corrosion due to use of mild steel, resulting in increased maintenance costs. BEML developed a prototype stainless steel EMU to address this issue. 2) The prototype utilized an austenitic stainless steel carbody, improved interiors, and underwent various tests from 2008-2013 before entering revenue service. 3) The stainless steel EMU demonstrated benefits like increased lifespan, reduced maintenance, and a more comfortable passenger experience. Indian Railways and other organizations have since placed additional orders for more stainless steel EMUs.

1. 7th OCT 2013

2. PROJECT BACKGROUND
 The present existing Electrical Multiple Units (EMU’s) running on sub-urban rail
network in metropolitan cities, are 3.66 m wide coaches manufactured with
Mild Steel material and painted.
 These EMU’s are prone to corrosion, especially in harsh environmental
conditions in coastal cities of Mumbai, Chennai & Kolkata.
 This results in frequent body repairs, increased down time and less availability
thereby reducing the revenue to Indian Railways.
 With the above background, a pro-active step was taken up by M/s
BEML Ltd, Bangalore Complex, R&D team
 Re-design the conventional mild steel body coaches with corrosion
resistant austenitic stainless steel material (life of 35 years).
 Carbody design which is modern, clean, aesthetically appealing
and more importantly which does not require any painting
 With world-class interiors.

3. PROJECT BACKGROUND
PROJECT HIGHLIGHTS:
 Development order from Indian Railways.
 Quantity: 2 rakes of 9 coaches each.
 Order Value: INR 40 crores for 2 rakes.
 Order received : 2008-09
 Scope: Design, Development, Manufacture, Testing, Commissioning & supply.
 Technical Requirements:
• 3.66 m wide Stainless Steel Carbody,
• World Class Interiors,
• Provision of forced air ventilation with ducting.
 Prototype completed: 2011-12
 Trials completed & put into revenue service : 2012-13

4. DETAILS OF PRODUCT
BRIEF SPECIFICATIONS:
 Track Gauge-Broad Gauge: 1676 mm,
 Max Speed : 100 kmph
 Coach length over body: 20726 mm,
 Max. width over body side: 3660 mm,
 Coupler height from rail level: 1035mm,
 Height of coach from rail level: 3618 mm,
 Maximum permissible axle load (Driving Motor coach & Trailer coach): 20.32 T,
 Max. height of the comp. floor from rail level under tare condition: 1230 mm,
 Rake Formation-9 Coaches: B-C-D-B-C-C-D-C-B
(B- Driving Motor Coach, C- Trailer Coach with Ladies Comp, D- Trailer Coach with Vendor Comp)

5. DETAILS OF PRODUCT
SUB SYSTEMS:
Sub – system
Features
 Carbody
Austenitic Stainless Steel carbody with unpainted exteriors
 Coupler arrangement
High capacity semi permanent coupling (Schaku couplers)
 Bogie
Primary Coil Spring & Secondary Air suspension for good riding
comfort
 Propulsion System
Electric propulsion system
 Brake System
Electro pneumatic brake system.
 Front end
FRP cab mask and cab skirt which provides a modern aesthetic
appeal to the coach.
Interiors
Designed to be on par with that of the world-class coach
interiors. FRP panels have been used extensively to provide
pleasant ambience for the passengers
Seat
Ergonomically designed passenger seats with polycarbonate
material and with dual tone shade to match the FRP interiors
Flooring
Anti-skid stainless steel floor cover sheets

6. DESIGN INNOVATIONS
 Design of wide bodied SS carbody structure with 16 passengers /
sqm loading (double of International & Indian metro standards)
was a challenging task
 Interior design was made with aesthetics & cost effectiveness in
mind, FRP panels used
 New design of window with wider opening. Design is having
provision for converting to Air-conditioned type with minimal
changes
 Passenger seats with polycarbonate material & dual tone shade to
match the interiors.
 FRP cab mask incorporated in the front to give a better look. FRP
driver’s desk ergonomically designed.

7. DESIGN & DEVELOPMENT EFFORTS
 Design effort involved:
 Development effort involved:
 Analysis of customers requirements,
 Manufacturing drawings
 Conceptual Design,
 Procurement technical specifications
 Detail design calculations
 Quality Documents.
 3D modeling
 Manufacturing of Prototype carbody
 Structural Integrity & Strength Analysis
 Design validation by squeeze testing
 Manufacturing, Furnishing & In-house
testing
 Testing and commissioning at
customers location.

8. DESIGN MODELING OF CARBODY
 Complete carbody modeled using CATIA V5 software.
 Carbody section to be within the allowable maximum moving dimensions.
 Weight reduction by 2 Tonnes
MOTOR COACH
TRAILER COACH

9. DESIGN OF INTERIORS
 CAD model of interiors, driver’s desk & cab mask prepared
 Interferences checked

10. STRUCTURAL STRENGTH VERIFICATION
 Structural Integrity & Strength Analysis of the carbody checked
 To meet UIC 566 standard,
 Analyzed using MSC Nastran software,
 Super dense passenger loading of 16 passengers / sqm
 Stress levels within acceptable limits.
TRAILER COACH
MOTOR COACH

11. CARBODY DESIGN VALIDATION – PHYSICAL TESTING
 Validation of carbody carried out by squeeze testing as per
UIC-566 standard with the following loads
Vertical Load L1: 75 Tonne
Compressive Load L2: 1200KN
Combined Load: L1+L2
PROTOTYPE MOTOR COACH CARBODY
DATA ACQUISITION
UNIT
PROTOTYPE TRAILER COACH CARBODY

12. MANUFACTURING INFRASTRUCTURE
 To meet the requirement of developing a world class coach, BEML has
established all the infrastructure required for manufacturing carbody and it’s
assemblies for SS EMU cars.

Robotic spot welding technology,

5 axis series spot welding,

CNC programmed Stretch Forming,
 Dedicated special Jigs & Fixtures.
 Custom built test facilities like water leak test, bogie load testing and test
tracks to ensure quality requirements.

13. MANUFACTURING INFRASTRUCTURE
ROBOTIC SPOT WELDING
5 AXIS SERIES SPOT WELDING
CNC PROGRAMMED STRETCH FORMING

14. MANUFACTURING INFRASTRUCTURE
UNDERFRAME MAIN ASSY JIG
SIDE BLOCK ASSY JIG
ROOF MAIN ASSY JIG
SIDE WALL MAIN ASSY JIG

15. CARBODY MANUFACTURE
 Manufacturing of Stainless steel
EMU carbody in production line.
TRAILER COACH CARBODY
MOTOR COACH CARBODY

16. CAR FURNISHING & ASSEMBLY
 Furnishing of Stainless Steel EMU in
production line.
INTERIOR VIEW
EXTERIOR VIEW
DRIVER DESK

17. INHOUSE TESTING
 Testing of furnished SSEMU rake in test track witnessed by RDSO/RITES.

18. FIRST PROTOTYPE RAKE
 First Rake Stainless Steel EMU rolled out from BEML Limited, Bangalore
Complex to Eastern Railways, Sealdah, Kolkata

19. COMMISIONING & FIELD TRIALS
 SSEMU has successfully undergone all the
extensive tests & trials by the customer, Eastern
Railways, Sealdah, Kolkata

20. REVENUE SERVICE
 This product was extensively tested by
the user railways and after successful
completion of trials for a period of six
months, this innovative product is running
successfully in revenue service at
Sealdah, Eastern Railways from Oct
2012 onwards.

21. VIDEO

22. COMPARISION OF SSEMU WITH
EXISTING MILD STEEL EMU
EXISTING MILD STEEL EMU
STAINLESS STEEL EMU
STAINLESS STEEL EMU & EXISTING MILD STEEL EMU

23. COMPARISION OF SSEMU WITH
EXISTING MILD STEEL EMU
STAINLESS STEEL EMU WINDOW
SS EMU WINDOW INSIDE VIEW
EXISTING MILD STEEL EMU WINDOW
EXISTING MILD STEEL EMU WINDOW INSIDE VIEW

24. COMPARISION OF SSEMU WITH
EXISTING MILD STEEL EMU
INTERIORS IN STAINLESS STEEL EMU
STAINLESS STEEL EMU SEATS
INTERIORS IN EXISTING MILD STEEL EMU
EXISTING MILD STEEL EMU SEATS

25. COMPARISION OF SSEMU WITH
EXISTING MILD STEEL EMU
INTERIORS IN STAINLESS STEEL EMU
FRP PANELLED PARTITIONS IN
STAINLESS STEEL EMU
INTERIORS IN EXISTING MILD STEEL EMU
SS PANELLED PARTITIONS IN
EXISTING MILD STEEL EMU

26. COMPARISION OF SSEMU WITH
EXISTING MILD STEEL EMU
STRAP HANGER IN STAINLESS STEEL EMU
FRP CEILING IN STAINLESS STEEL EMU
STRAP HANGER IN EXISTING MILD STEEL EMU
LP SHEETS PANELLED CEILING IN
EXISTING MILD STEEL EMU

27. CUSTOMER FEEDBACK
 The indigenously designed & developed SS EMU has successfully undergone
all the stringent tests & trials of the customer, IR
 User satisfactory performance certificate received.
 Based on the successful user trials, further order of 4 rakes (36 cars) has been
received from IR
 MD, MRVC (Mumbai Rail Vikas Corporation) after his visit to BEML had made
the following observations
“ We were extremely happy to observe the international standard achieved by
BEML in the design & manufacture of stainless steel coaches for Metro &
Suburban railway system in India. “

28. CUSTOMER FEEDBACK

29. CONTRIBUTION TOWARDS SELF RELIANCE
 SS EMU designed & developed for Indian Railways for the first time through inhouse R&D efforts without any foreign collaboration.
 Stainless steel carbody joining / manufacturing process established which will
be helpful for other projects.
 Stainless steel raw material of desired specification developed by indigenous
sources.
 Interior furnishing items developed through indigenous sources.
 Future requirements of rolling stock variants with stainless steel carbody can
be developed within the country.

30. KEY IMPACTS
 With introduction of SS EMU latest stainless steel carbody similar to the
metro cars brought in IR.
 Use of Stainless steel will increase the life of the coaches (25 to 35 yrs) & also
reduces maintenance time, thereby reducing the life cycle cost.
 Use of austenitic stainless steel has eliminated painting, making it eco friendly.
 Common man can have the pleasure of travelling in a better coach at the same
cost.
 Product well accepted, IR placed additional order for SS EMU & MRVC floated
requirement for 153 nos. SS cars.

31. FUTURE READINESS
 Based on the successful commercial service of prototype rake, Indian
Railways have placed additional supply order for 4 rakes of SSEMU valuing
about 84 crores.
 Indian Railways plans to replace the existing 3000 no’s of Mild Steel EMU
coaches with the newly developed Stainless Steel EMU’s. Total business
expected from SSEMU is about INR 1000 crores per year.
 Mumbai Rail Vikas Corporation (MRVC) were impressed by unique features of
the SSEMU prototype rake and have floated requirement for 153 SSEMU
coaches for their harbour line.
 Considering the benefits of stainless steel carbody, future production of other
EMU’s is expected to be manufactured with SS.
 Tier – II cities can adapt this technology with minimal changes for low cost
metro rolling stock.