Near-isothermal forging technology developed
The Defence Research and Development Organisation (DRDO) has announced a modest step towards achieving the ultimate aeronautical challenge, one that even resource-rich China is struggling to achieve: Developing a jet engine with the thrust to power a fighter in combat. The DRDO established the near-isothermal forging technology to produce all the five stages of high-pressure compressor (HPC) discs out of difficult-to-deform, titanium alloy, using its unique 2000 MT (metric tonne) isothermal forge press, announced the Ministry of Defence (MoD).
- This technological breakthrough, which involves developing complex titanium and nickel-based alloys that can withstand temperatures of more than 1,000 degrees Celsius, was achieved by the DRDO’s premier metallurgical laboratory, the Hyderabad-based Defence Metallurgical Research Laboratory (DMRL).
- With this development, India has joined the league of limited global engine developers to have the manufacturing capabilities of such critical aero-engine components.
- Using the isothermal forge press facility available at DMRL, Hyderabad, DMRL & MIDHANI have jointly produced 200 HPC disc forgings pertaining to various compressor stages.
- These have been supplied to HAL’s Engine Division in Bengaluru for fitting into the Adour 804/811 and 871 engines that power the Indian Air Force’s (IAF’s) Jaguar/Hawk Aircrafts.
- The Adour engine is overhauled by HAL, Bengaluru under a licensed manufacturing agreement with Rolls-Royce, the original equipment manufacturer (OEM).
- A fighter jet engine functions by sucking in a large volume of air, compressing it rapidly in several stages, injecting aviation fuel into the air and then setting it alight to create a high-pressure, high-temperature gaseous mix. That is expelled backward through the exhaust, its reaction propelling the aircraft forward.
- To achieve this, jet engines have seven modules, which from front to rear are: the input fan, low pressure and high pressure compressors, the combustion chamber, high pressure and low pressure turbines and the exhaust.
- An aero-engine requires finely tuned design and manufacture. For over three decades the DRDO’s Gas Turbine and Research Establishment (GTRE) has spearheaded a multi-laboratory effort to design the so-called Kaveri engine, but with only limited success.
- The (Kaveri) project was sanctioned in March 1989 at an estimated cost of Rs 382.81 crore and Probable Date of Completion (PDC) of December 1996.
- The PDC was extended to December 2009 and cost was revised and enhanced to Rs 2,839 crore.
- Even so, the Kaveri’s has achieved a thrust of just about 65 Kilo Newtons (KN), well short of the 95 KN that its premier rivals, the Eurojet EJ200 and the General Electric GE-F414 develop.
- The DRDO is now exploring the possibility of using the Kaveri as a marine propulsion turbine for warships.
- DMRL, which developed the technology to produce the five-stage HPC discs, is a laboratory without the facilities for bulk production.
- To manufacture the discs in the volumes required, DMRL has transferred technology to defence public sector undertaking (DPSU) MIDHANI through a licensing agreement for technology transfer (LAToT).