Semi-cryogenic propellant tank


    In News 

    The heaviest semi cryogenic propellant tank (SC120­ LOX) ever fabricated by Hindustan Aeronautics Limited (HAL) has been delivered to the Indian Space Research Organisation (ISRO). 


    • The semi cryo liquid oxygen (LOX) tank — the first developmental welded hardware — is a part of the SC120 stage intended for payload enhancement by replacing the L110 stage in the existing Mk­III launch vehicle.
      • In 2020 ,HAL had delivered the biggest ever cryogenic liquid hydrogen tank (C32­LH2), four meters in diameter and eight meters in length, much ahead of contractual schedule.
    • HAL has delivered critical structures, tankages, satellite structures for the PSLV, GSLV­Mk II and GSLV­Mk III launch vehicles. 



    What is a Cryogenic engine?

    • It is the last stage of space launch vehicles which makes use of Cryogenics.
      • Cryogenics is the study of the production and behaviour of materials at extremely low temperatures (below -150 degree Centigrade) to lift and place heavier objects in space.
    • Cryogenic stage is technically a much more complex system with respect to solid or liquid propellant (stored on earth) stages due to the usage of propellants at extremely low temperatures. 
    • A cryogenic engine provides more force with each kilogram of cryogenic propellant it uses compared to other propellants, such as solid and liquid propellant rocket engines and is more efficient.
    • Cryogenic engines make use of Liquid Oxygen (LOX) and Liquid Hydrogen (LH2) as propellants which liquefy at -183 deg C and -253 deg C respectively. LOX and LH2 are stored in their respective tanks. 

    What is a Semi-Cryogenic Engine?

    • Unlike a Cryogenic engine, a Semi Cryogenic engine uses Refined kerosene instead of liquid hydrogen. The liquid oxygen is used as a Oxidiser. 
      • That’s the advantage of using a Semi Cryogenic engine as it requires Refined Kerosene which is lighter than liquid fuel and can be stored in a normal temperature. 
    • Kerosene combined with liquid oxygen provide a higher thrust to the rocket. Refined Kerosene occupies less space, making it possible to carry more propellant in a Semi Cryogenic engines fuel compartment.
    •  A semi cryogenic engine is more powerful, environment friendly and cost effective as compare to cryogenic engine

                                          Image Courtesy:DH