Shakeel Akhtar, Ranchi:
High amount of hydrogen in the steel of the return shaft, lack of grease and improper tension management are the main reasons for the Trikut ropeway accident. The Central Mechanical Engineering Research Institute has mentioned these facts in the report sent to the committee constituted by the government to investigate the rope-way accident after investigating the causes of the accident. The committee has also recommended to conduct a safety audit before starting the ropeway in future and to make necessary changes according to the audit report, because there is a possibility of damage to the rest of the equipment of the ropeway after the accident.
It was said in the report that the rope-way accident took place due to breakage of the return shaft. The institute, which examined the broken return shaft, found that the steel used to make the shaft had a hydrogen content of 5.62 ppm (87% more), whereas it should have been 2-3 ppm. Due to the high amount of hydrogen, layers were formed in the shaft and cracks were created. At the same time, the volume of grease should be nine under the prescribed standard in bearings etc. in ropeway, while it was only 0.96. This caused excessive friction in bearings, shafts and other components.
Apart from this, the tension management of the ropeway was also not correct. This put excessive pressure on the return shaft and it broke. The ‘bull wheel’ shifted from its place due to the breakage of the return shaft. At the same time, a trolley was returning from Upper Return Station (UTP). She broke free from the rope and fell to the ground and the rest of the trolleys came to a halt with a heavy vibration.
Questions were also raised on the operation and maintenance of the ropeway:
In the report submitted to the committee, questions have also been raised on the operation and maintenance of the ropeway. It has been said that the people engaged in the operation were not fully trained and efficient. BIS standards prescribed for ropeway were not complied with. It has been said in the report that BIS standards were set after the construction of Trikut ropeway. That’s why later it was decided to meet BIS standards in this ropeway, but it was not completed.
Before the accident, the shaft of the rope-way was examined twice in the year 2016, once in the year 2018, 2019 and in the year 2021, but in any of the investigation reports, there was no evidence of high hydrogen content or any other defects in the steel of the shaft. Wasn’t mentioned. Only in the inspection reports of 2016 and 2018, it was mentioned that 100 percent shafts were not inspected.
The following officers were included in the inquiry committee:
The state government constituted a committee to investigate the accident, in which Finance Secretary Ajay Kumar Singh, then Secretary Amitabh Kaushal, Director Mines Safety (Mechanical) Ratnakar Sunaki, National Highway Logistics Management Consultant (Rope-way) NC Srivastava, ISM Dhanbad Kabir Das Gupta, Professor of Mechanical Engineering. The committee had decided to get the test done from the government laboratory. The committee got the material test, metallography, surface defect test, cause of failure of shaft and thrust bearing checked.
