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8 Cards in this Set
- Front
- Back
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High Pressure (HP) turbine
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Made by General Electric, the HP turbine is an 8 stage impulse turbine. The energy in main steam is converted into mechanical energy (high speed, low torque rotation) which is applied to the reduction gears. Main steam is supplied to the J3P turbine in the ahead direction only then is exhausted to the LP turbine.
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Low Pressure (LP) turbine
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Made by General Electric, the LP turbine is an 8 stage (7 ahead, 1 astern) impulse turbine. Energy in main steam is converted in the same manner as the HP turbine and applied to the reduction gears. In the ahead direction, main steam exhausted by the HP turbine is directed to the LP turbine via a crossover pipe then is exhausted to the main condenser. In the astern direction, main steam is directed
to the one stage of astern elements located on the fwd end of the LP turbine then exhausts to the main condenser. |
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Main condenser
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The primary purpose is to condense the steam exhausted by the LP turbine back into water (condensate). The cooling medium is seawater provided by either scoop injection or the main circulating pump. Seawater goes through tubes while steam goes around the tubes.
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Main circulating pump
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A steam driven (600 aux) propeller type pump used to provide seawater (22,000 gpm max) to the main condenser when the forward speed of the ship is below 8 knots. In case of major uncontrollable flooding, the main circulating pump can take a suction from the bilge to de-water the space at a maximum rate of 5,000 gpm.
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Guarding valves
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Valves used to isolate main steam from both the hp and LP turbines prior to the throttle valves. In an emergency (k-jammed ahead throttle) the ahead guarding valve can be used to control the forward speed of the ship, below the speed when the throttle jammed.
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Ahead throttle valve
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A remote hand wheel located in the EOS and connected to the hp turbine via metal rods and gear boxed and knuckles. The ahead throttle valve operates the beam which controls the amount of main steam admitted to the hp turbine.
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Astern throttle valve
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A remote hand wheel located in the eos connects to the ahead throttle valve which control the amount of main steam admitted to the astern elements of the LP turbine.
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Thrust bearings
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In the main engine, thrust bearings prevent axial (for and aft) movement of the turbine rotors. On the shaft, a Kingsbury type thrust prevents axial movement of the shaft and transmits the thrust developed by the screw to the hull moving the ship either forward or aft.
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