Space

Avasarala enjoys a unique distinction of having achieved space quality certification process for its processes and components with successful establishment of critical heat pipes for satellites. The products have found its way into satellites and a continued long term commitment from our clients testifies to the customer confidence. Avasarala supplies critical machinery for the space launch programs and other critical equipment.

Avasarala has been actively associated with Space Sector since 1998 and has worked on a variety of critical and technologically challenging projects.

 

Products

  • Heat pipes.
  • Wave Guides.
  • Mechanisms.

Heat pipes

Heat pipes typically provide a quick mechanism to transport heat from the spacecraft electronics and instruments to its radiators. These are two phase heat transfer devices circulating a working fluid such as ammonia that evaporates and condenses to transport heat. Heat pipes provide a highly energy efficient means to transport hundreds of watts of thermal energy across several metres.

Heat pipes can be embedded within a honeycomb panel and bonded to the inner surface of the face sheets to achieve highly efficient heat removal. Surface mountable heat pipes with flanges attach to heat pipe panels to transfer heat from internal equipment to external radiator panels.

The heat pipes have been successfully supplied for various satellite programs such as GSAT-3 (Edusat), INSAT-4A, INSAT-4B, INSAT – 4CR, CARTOSAT-2A, CHANDRAYAAN, EADS – EUTELSAT – W2M, AVANTI HYLAS, GSAT-4, OCEANSAT-2, RISAT, GSAT-5, GSAT-5/3E, GSAT-8, ASTROSAT, GSAT-12, SS LORAL, ETC.,

Supply of Space quality heat pipes of different cross-section & configuration for various Space Programmes.

 

Thermal Specifications:

Type of heat pipe

Dual core constant conductance heat pipe

Operating Temperature range

-40°C  to  +60°C

Heat Transport Capability of each core

Straight Heat Pipe : >150 Wm. @ 20°C and >120 Wm at +60°C with temperature gradient less than 5°C for an input/output heat flux of 1.5W/cm2 in horizontal condition        ( i.e. under near 0-g condition)

Bent Heat Pipe : The performance degradation will not be more than 5% per bend of the straight pipe for bend radius of 50 mm & bend angle of 90°

Non Condensable Gas Plug length

Less than 5mm @ - 40°C Heat pipe temperature

Mechanical Specification

Dimensional control details and finish

Flatness          : 0.10mm per 300mm and 0.20mm per full length
Roughness   : 0.008mm.
Parallelism   : 0.20mm per 1000mm
Straightness : 0.50mm per 1000mm
Visual defects           : scratches, digs and dents
(not deeper than 0.08mm)

Proof Pressure Test 189 kg/cm2 at room temperature
Burst Pressure Test 255 kg/cm2 min (Destructive test on sample basis)
Shape As per customer requirement (ex: Straight, L-Bend, Multi Bend, S-Bend & two plane bend etc.)
Material & Working Fluid  
Envelope tube material Aluminum alloy 6063-T6 or equivalent
Wicking system Axial grooves (extruded type)
Welding Tungsten Inert Gas welding
Helium Leak Test Less than 1x10-8 S CC/sec
Working Fluid Ultra High Purity - Anhydrous Ammonia
(Water vapour content  <1 PPM )
Leak rate for Ammonia Less than 1 x10-7 s cc/ sec at envelope
Less than 1 x 10-6 s cc/sec between two vapour cores

 

Wave Guides & Mechanisms:

Avasarala offers critical space grade Al section waveguides with critical dimensioning, shapes, with dip brazed flanges and silver plated internals.

Products shall be custom built to individual requirements.The products have been approved for space applications.

 

Equipments:

Avasarala has been a pioneer in providing various critical ground equipment to the space industry. Starting from developing critical thin film burr free punching to Ion beam polishing systems have been designed and developed successfully.

Equipments to Space Industry:

  • Ion Beam Polishing System.
  • CNC Perforating Machine.
  • Thermo Vacuum Chamber.
  • Conformal Coating System.
  • Vacuum Baking Chamber.

ION BEAM POLISHING SYSTEM:

A turn key developmental project for non-contact nano-level polishing of 1 meter diameter optics employed in satellites for earth imaging. Work consisted of conceptual designing, engineering drawings, global sourcing of customized sub-systems, development of software to interface various sub-systems, demonstration of process, installation on site and commissioning. Typical sub-systems are

  • Stainless Steel high vacuum chamber .
  • Five axes manipulator to work in high vacuum .
  • Low energy ion broad beam sources complete with power supply.
  • Optic mounting and rotating fixture.
  • High vacuum pumping system complete with gauges and instruments.
  • Electro-mechanical robot for handling optics.
  • Complete electric power and control system.
  • Laser Interferometer with supporting interfaces.
  • SCADA Soft ware for interfacing.

Criticalities:

  • A unique and a highly technologically challenging development through interactive approach.
  • Gravity compensated optic mounting.
  • Extensive trials to demonstrate the process and consistency in process reproducibility.

The turn key project could successfully polish Zerodur optics to a surface finish of λ/60 i.e. 10 nano-meters (RMS) absolute as specified.

 

Features:

  • SS-304L Chamber: 3.2m dia/ 2m long.
  • Vacuum: 1x10-6 mbar.
  • Ion Guns: 16 Cm.
  • Vacuum Compatible 5 axes movement.
  • Software for laser interferometer output.
  • Data Acquisition System.
  • Non contact machining of precision glass & silicon carbide.
  • CNC Controls to interface with interferometer output.

CNC PERFORATING MACHINE

CNC Perforating Machine for making tiny precision holes on Aluminized Mylar and Kapton films.It makes holes, which are free from burrs and ensures non tearing of the film around the edges. Fully programmable options for hole patterns.

THERMO VACUUM CHAMBER:

A turn key development project for testing of satellite packages for Thermal cycling and RF Shielding parameters. Work consists of conceptual designs, engineering drawings, global sourcing of customized sub-systems. Software to interface, demonstration of process, site installation and commissioning. Typical sub-systems are,

  • Stainless Steel high vacuum chamber .
  • Package mounting platform.
  • RF Shield.
  • Thermo Panels.
  • High vacuum pumping system complete with gauges and instruments.
  • Complete LN2 and GN2 system with controls and instruments.
  • Electrical power and control system.
  • Software for interfacing.

Criticalities:

  • Establishing technically challenging customized sub-systems.
  • User friendly configuring for either thermal or RF Shielding.
  • Extensive trials to demonstrate the process and consistency in process reproducibility.

Successful completion of the project proved another milestone in the development of highly technical challenging multi engineering test setup for satellite packages.

CONFORMAL COATING SYSTEM:

Developed in technical arrangement with ISRO for uniform conformal coating of PCBs for space applications.

 

Services:

Avasarala provides onsite thermal system services for satellite integration and assembly in clean room environment. The highly skilled thermal system team provides the following services:

  • OSR Bonding.
  • Multi-Layer Insulation - MLI Fab & Implementation.
  • Tape Heater.
  • Foil Heater.
  • PRT/Thermistor .
  • Thermal Control Tape.
  • Thermal Painting.
  • Thermal Grease Application.
  • Thermal Properties Measurement and Testing Services.

Avasarala’s Space group skill sets:

  • Copper - Copper welding in an inert atmosphere enclosure.
  • Aluminium – Aluminium Welding using TIG technology for high pressure application conforming to level 2.
  • Stainless steel – Stainless steel FUSION welding.
  • DIP Brazing for Aluminium joints formation (Space grade reliability approved).
  • Manufacture of high precision components with surface treatment such as Chromatising, hard anodising, etc.

Application areas:

  • Aeronautical.
  • Space.
  • Medical.
  • R&D.

Service capabilities:

Electrolyzing – A process of Hard Chrome plating, hardness achieved is in the range of 65 min HRC to 71 HRC;Thickness:10 microns to 25 microns.

Nickel Forming – A highly specialised capability to produce extremely thick Nickel surfaces required for    critical applications. A Nickel coating of 2000 microns with in a tolerance limit of 20 microns with hardness in the range of 135 VHN.

Copper to Copper Welding– A special capability to weld copper parts in a precise way. Using TIG welding facility and in enclosed atmosphere.