Once the ground crew confirms normal operation confirm the inspection; the officer starts other pumps in parallel and pumps speed and pressure. Cargo pumps should not be started until the inert gas system is in operation; cargo and ramp tanks are common (parallel). In addition, the cargo is unloaded; the exhaust valve should be closed with the valve open. Once it is confirmed that the onshore facility receives cargo at its end; slowly move the pump to its nominal full speed. If multiple cargo pumps run in parallel; they need to have the same operating speed and pressure to maintain cargo flow. Changes will cause the pump to overheat, no flow output or pumping loss.
The entire pump structure can be divided into two key parts; rotating and stationary components. The impeller and the shaft constitute a rotating structure; the volute occupies a fixed portion. Centrifugal pumps are suitable for handling low and medium viscosity fluids. Their oil pump motors have high-capacity output and dynamic magnetic heads. In addition, it is a dynamic pressure pump; it allows controlling the output without changing its operating speed or dangerously pressurizing the system. For centrifugal pumps used as cargo pumps, they are equipped with an additional non-return valve at the output for backflow.
When used as a main cargo oil pump, a centrifugal pump turbine or COPT has two main parts; a turbine and a centrifugal pump. Steam turbines consist of components such as boilers, feed pumps, condensers and turbines, which work together in a closed loop system. The high-pressure steam from the turbine casing passes through a series of inlet nozzles. These nozzles convert high-pressure steam into high speeds, directing them onto turbine blades; rotating with the shaft to generate rotational power. The generated power is then transmitted to the centrifugal pump through the connecting shaft. The exhaust steam returns to the boiler through the condenser and feed pump. Centrifugal pumps, on the other hand, work on the simple law of centrifugal force. The pump impeller throws the fluid out of the axis. This process transfers part of the kinetic energy of the impeller to the fluid; it then passes through the volute to leave pressure. The pressure difference due to a sudden change in fluid volume creates a partial vacuum behind the impeller eye; this creates a much-needed suction pressure to continue the process.