The Indian Navy will commission its third Scorpene-class submarine–the INS Karanj–in Mumbai on 10 March, a person familiar with the development said on Monday. The Navy has inducted two submarines of the same class–the INS Kalvari and INS Khanderi–from Mazagaon Docks Limited (MDL’s) where the INS Karanj was also built.
The INS Karanj was handed over to the Indian Navy on February 15. The submarine is the third out of the six submarines that will add teeth to the Indian Navy. Initially, the submarine was supposed to be commissioned into the Indian Navy by mid-2019 but got delayed. The construction of the submarine began 10 years and five months ago and finally it will be inducted into the Navy. The pressure hull fabrication of the submarine began in October 2010. The pressure hull is the primary structural element of the submarine and is designed to be able to withstand external hydrostatic pressure. It is designed for a particular collapse depth, at which complete failure is expected within a very narrow range. The collapse depth is calculated by multiplying the maximum operable depth (MOD) or service depth with a factor of safety. The hydrostatic pressure at this depth is considered as the design pressure for all the pressure hull calculations.
According to the agreement with the Government of India, a total of six submarines are to be built in this shipyard. Of which, the trials of Vela and Wazir are underway, while the construction of the sixth submarine is going on. The sixth boat of the Scorpene or the Kalvari class had been named Vahsheer.