🔍 Key Concepts

• Difference between positive displacement rotary pumps and reciprocating pumps • How capacity vs. weight/size typically compares between pump types used on ships • Meaning of slippage in pumps and which pump type is more/less affected

💭 Think About

• Think about which pump type is generally more compact for the same capacity on board ships: rotary or reciprocating? • Consider whether rotary pumps are known for very high pressure, or more for steady flow and good capacity at moderate pressures. • Ask yourself which pump type usually has more moving parts and larger foundations for the same output.

✅ Before You Answer

• Be clear on what slippage means (internal leakage past clearances) and which pump type tends to have more of it. • Compare weight vs. capacity: for the same output, which pump would usually be lighter and smaller? • Check whether it sounds realistic that any pump type would cleanly eliminate all discharge slippage under normal conditions.