Chennai Metro Rail Limited (CMRL) has been in passenger services since 2015. Providing an unparalleled comfortable service and safety to passengers is the core vision of the organisation. For the last 6 years, the Chennai Metro Trains have been carrying passengers on time. To ensure safety and reliability of Metro Trains, intermediate overhauling (IOH) of trains is performed as per the requirements of Original Equipment Manufacturer (OEM) Maintenance Manuals.
- The work involves removing the bogies (undercarriage with four or six wheels pivoted beneath the end of a Metro Train Vehicle) from the car body and stripping out of bogie components.
- Inspection of welding joints, welding and repainting of bogie frames are then done.
- Primary suspension springs are 100% replaced.
- The wheels are re-profiled for passenger comfort.
- The axles are then subjected to Ultrasonic flaw testing to ensure that no internal defects exist.
- Other worn-out components are also replaced during this process.
- A complete overhaul of traction converters, auxiliary converters, brakes system and air conditioning system are also performed.
- In addition, deep cleaning of air conditioner ducts, train exterior and interior is also performed using special environment-friendly chemicals.
- All components are re-assembled to bogie frames as per international best practices.
- The bogies are levelled in a static bogie testing machine.
- After the completion of all related works, the bogies are run in, and the car body is lowered.
- The train is subjected to level adjustments to maintain floor height inpar with platform level.
- The Metro Train undergo static tests and all functionalities are restored.
- Then dynamic tests are also carried out in test track up to 40 kmph and in mainline up to 80 kmph.
- The Metro train is then certified fit for passenger service by Competent Authority.
- The Metro Trainset No. 15 is the first trainset to be overhauled by CMRL ‘s in-house team in coordination with Maintenance Staff.
- The cost of overhauling one trainset is around INR 1.77 Cr and time taken for completion of the entire process is 40 days.
- Pradeep Yadav, I.A.S., Managing Director, CMRL inspected the first overhauled Metro Train set from CMRL Rolling Stock Maintenance Facility at Koyambedu on 15-09-2021.
- Rajesh Chathurvedi, Director (System and Operations), Senior Officials and Staff of CMRL were present during the inspection.
Source: CMRL-Press Release | Image Credit (representational): CMRL
