ISRO hot-tests additive-manufactured rocket engine

Bengaluru: The Indian Space Research Organisation (ISRO) has successfully hot-tested a liquid rocket engine manufactured through additive manufacturing (AM) technology.

Over 11 minutes and 5 seconds, the hot test – conducted on Thursday at the ISRO Propulsion Complex in Mahendragiri, Tamil Nadu – validated key performance parameters of the redesigned PS4 engine.

Additive Manufacturing involves a fabrication process that deposits materials on materials to create objects in a 3D form.

The conventionally manufactured PS4 engine has been in use in the fourth stage of the Polar Satellite Launch Vehicle (PSLV), India’s workhorse launcher, and in the Reaction Control System of PSLV’s first stage (PS1).

Developed by ISRO’s Liquid Propulsion Systems Centre (LPSC), the engine works on combinations of Nitrogen Tetroxide as oxidiser and Mono Methyl Hydrazine as fuel in the pressure-fed mode.

The LPSC redesigned the engine in line with the Design for Additive Manufacturing concept, bringing in multiple advantages. The new manufacturing process brought down the number of parts from 14 to a single-piece, eliminated 19 weld joints, saving significantly on the raw material usage per engine (13.7 kg of metal powder, compared to the 565 kg of forgings and sheets for conventional manufacturing process) and reduced 60 per cent in the overall production time, ISRO said on Friday. The manufacturing of the engine was done by Wipro 3D.

ISRO had earlier validated the engine’s injector head and carried out preparatory analyses ahead of four successful developmental hot tests on the integrated engine, for a cumulative duration of 74 seconds. “The engine was successfully tested for the full qualification duration of 665 s and it was observed that all the performance parameters were as expected,” ISRO said.

The space agency said it planned to induct the AM PS4 engine into its regular PSLV programme.