For making metallic pipes, a continuous casting method, known as Osprey process is utilized. This method is cheaper to produce metallic pipes in comparison to traditional pipe manufacturing techniques. In this process the molten metal is sprayed over a rotating mandrel to produce seamless tubing and pipes. The Osprey process is essentially a rapid solidification technique for the direct conversion of liquid metal into shaped preforms by means of an integrated gas-atomizing /spray-depositing operation. In the osprey process, a controlled stream of molten metal is poured into a gas-atomizing device where it is impacted by high-velocity jets of gas , usually nitrogen or argon. The resulting spray of metal particles is directed onto a "collector" where the hot particles re-coalesce to form a highly dense preform.
Steam Pressure at inlet to a steam turbine is reduced by throttling process to maintain the speed of the turbine constant at part load and hence this method of governing is called "Throttle Governing". Construction : Throttle governing system consists of a centrifugal governor, a lever , an oil pump , a pilot piston , control valve , a relay piston and a throttle valve. The throttle valve is moved by a relay piston. The relay piston is actuated by pilot piston control valve. There are two piston valves covering ports in the pilot piston control valve without any overlap. These piston valves are operated by lubricating oil supplied by a gear pump at 2 to 4 bar. The oil returns to the drain from this chamber. Working : When the turbine works on full rated load, the throttle valve will remain open. When the load is decreased, the energy output of the turbine becomes in excess and the turbine shaft speed increases. Hence, governor sleeve will lift. The upward movement of the
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