BENGALURU: India’s ambitious first-manned ocean mission Samudrayaan is inching closer to reality, with ISRO on Wednesday announcing that the testing of the personnel sphere of the Matsya-6000 submersible, along with the development of materials for realisation, were successfully carried out at the Vikram Sarabhai Space Centre (VSSC).
“The first welding on the actual hardware and detailed evaluation has been completed. High-penetration welding of this scale, ie. of 80-mm weld thickness, over 7,100-mm length with 32 minutes of weld duration, was carried out for the first time in the country,” ISRO said.
Matsya-6000 is a sphere comprising a diameter of 2,260-mm, made of Titanium, and is expected to withstand external pressure of up to 600bar under low temp situations of -3 degrees C. It is capable of carrying a three-member crew, up to 6 km deep into the ocean.
The National Institute of Ocean Technology (NIOT) signed an MoU with VSSC for the development of the special human-occupied spherical vessel, as a part of Samudrayaan, under the Deep Ocean Mission.
The scientists also said a major challenge in realising the spherical vessel was the development of reliable, high-penetration Electron Beam Welding process and the high-energy (7.5MeV) X-ray facility for the Non-Destructive Evaluation. This is essential for the certification of the human-rated product, the ISRO team said.
The Liquid Propulsion Systems Centre (LPSC) in Bengaluru developed the process and infrastructure for the welding process and NDE. ISRO said the LPSC has the facility and expertise to carry out welding up to 20-mm thickness.
To meet the high-power demand, the EBW machine was augmented from 15kW to 40kW rating, along with additional facilities for chemical cleaning and handling equipment for the higher size and mass. For the NDE, the existing X-ray facility in kV range was augmented to 7.5MeV range. Multiple NDE techniques were employed, which complement each other in ascertaining weld quality, including Time of Flight Diffraction and Dual Linear Array Phased Array Ultrasonic Testing, the team concluded.