Hindustan Aeronautics Limited (HAL) has commissioned and operationalised a Hot Isostatic Press (HIP) facility at its Nasik Division to process carbon-carbon brake discs for the Light Combat Aircraft (LCA) Tejas Mk 1A. The facility enables high-temperature, high-pressure densification of carbon-carbon composite components used in the aircraft’s braking system.
The specialised carbon HIP system is designed to process Carbon-Carbon Brake Discs (CCBD), which are critical components of the LCA Tejas Mk 1A braking system. Carbon-carbon composites are naturally porous after initial manufacture, and the HIP process densifies the material by removing internal voids under uniform pressure and elevated temperature to ensure the structural integrity required for aircraft braking applications.
The facility was commissioned and operationalised on 13 March in the presence of Rajesh Kumar Singh, Defence Secretary of India, and D. K. Sunil, Chairman and Managing Director of Hindustan Aeronautics Limited, during the inauguration ceremony at the company’s Nasik Division.
The installation of the facility was carried out through phased tenders issued by HAL. In December 2022, the company floated a tender for the construction of a building and associated infrastructure for the HIP installation at its Nasik site with an estimated value of INR 76.3 million. HAL subsequently invited bids for a two-year operation and maintenance contract for the press under Contract No. SPR/24/62, with an estimated value of INR 42.5 million and a requirement for prior experience in operating or maintaining carbon HIP systems and graphite-based aircraft components.
The HIP system supplied for the facility was manufactured by ASACO Private Limited, a Hyderabad-based engineering company that produces metal-forming equipment, wire and cable machinery, and specialised heavy-duty presses. The company has previously supplied hot isostatic press equipment for India’s space sector, including a V-50 HIP delivered to the Vikram Sarabhai Space Centre (VSSC), the Indian Space Research Organisation’s launch vehicle development facility in Thiruvananthapuram, Kerala.
For the VSSC project, the HIP system was developed in collaboration with Isostatic Forgings International (IFI) of the United Kingdom. ASACO handled global procurement, local assembly, and the final supply of the equipment for the installation.
Hot isostatic pressing is an industrial process used to eliminate internal porosity in materials by subjecting components to simultaneous high temperature and uniform pressure within a sealed vessel. In the process, manufactured components such as porous carbon-carbon brake discs or additive-manufactured metal parts are placed inside a reinforced pressure vessel, which is then sealed and evacuated of ambient air.
The chamber is subsequently filled with an inert gas, typically argon, and heated to high temperatures. As the gas expands, it generates internal pressure that can exceed 15,000 pounds per square inch. Because the pressurised gas surrounds the components entirely, it applies uniform pressure from all directions, collapsing microscopic voids and defects without altering the external shape of the part.
Following controlled cooling and depressurisation, the resulting components emerge fully densified, improving structural integrity, fatigue life, and resistance to extreme operational stress. In aerospace applications such as fighter aircraft braking systems, this densification process enables carbon-carbon composites to withstand repeated friction loads and thermal shocks during landing operations.
Hindustan Aeronautics Limited is an Indian aerospace and defence company engaged in the design, development, manufacture, and maintenance of aircraft, helicopters, engines, and aerospace structures. The company operates manufacturing and maintenance divisions across India supporting military and civil aviation programmes.
