N E W S L E T T E R
NEW TEST FACILITY
KTM-1000 Machining Facility
The Gas Turbine Research Establishment (GTRE), Bangalore, has installed an HMT-KTM-1000 CNC-controlled horizontal spindle machining centre for manufacturing certain components of Kaveri engine. The main components of the facility are: main machine unit, control unit and hydraulic power supply. The machine unit has three perpendicular turning axes with a fourth rotary axis. The auxiliary components of the machine consist of pallet shuttle-(a mechanism for changing work piece by a conveyor chain driven by hydraulic motor through gearbox), automatic tool drive selection mechanism, and an automatic tool changer mechanism. The control unit, is a specifically designed unit called Sinumeric 3M CNC which is a 3-D contouring control keyboard programme unit, equipped with resolver. The feedback is capable of controlling three axes motion of the machine. Hydraulic power-pack supplies oil pressure to the moving parts of the machine. Casings for compressor, fan split, intermeDIATe, and turbine components are manufactured using this facility. This facility is used only for milling operations.Sqeeze Film Damper Test Facility
The Squeeze Film Damper Test Facility has been set up in GTRE to study the effects of various parameters of squeeze film damper on the rotor performance of gas turbine engines. A scaled-down model of test rotor with full-scale damper geometry is tested with the help of this facility. The rig consists of two mass rotor systems (one overhung mass), supported on squeeze film-mounted anti-friction bearings at two points. The drive system is a thyristor-controlled DC motor coupled through pulleys. The maximum rotational speed is 9000 rpm. The instrumentation contains eddy current type displacement pick-ups to measure displacement in X and Y planes force transducer and phasemeters to measure phase relation between displacement and force transmitted at damper supports. Rotor speed is sensed by magnetic pick-ups. These signals are recorded on a 24 channel U-V recorder. The external unbalance and location of overhung mass can be altered to study the effect of extreme dynamic conditions on rotor behaviour. The damper effects on rotors can be analysed, based on the readings of vibration at various rotor planes, rpm, damper oil supply pressure, amount of unbalance created at two planes, geometry of different dampers and rotor assembly critical speed. This rig has been actively used for testing squeeze-film damped anti-friction bearings of Kaveri K1, K2 and K3 engines in GTRE.
The Laser Science & Technology Centre (LASTEC), Delhi, in collaboration with a Russian agency has developed a high energy EOCM class of solid-state laser with a sophisticated automatic beam pointing and focusing capability. The facility is named as Shalaka and is fully operational at the Metcalfe House Complex, Delhi. Shri R Ramanathan, Addl FA, inaugurated the facility, on 6 October 1999. Presently, Shalaka is under testing for longer ranges (up to 3 km).