A duplex double-acting reciprocating feed water pump has what ratio of steam pistons to water pistons?

In a duplex double-acting reciprocating feed water pump, the design incorporates two steam pistons for every two water pistons, which aligns with the notion of a balanced operation. The "double-acting" aspect indicates that each piston has two strokes – one for each side of the pump, enhancing efficiency in water delivery.

The term "duplex" refers to the presence of two distinct pump units working together in harmony. With this setup, each steam piston powers the corresponding water piston, ensuring that for every cycle of steam applied, an effective volume of water is moved. This configuration allows for a seamless and continuous flow, optimizing the overall performance of the water feed system in a steam-based application.

Thus, a ratio of "2 to 2" signifies that there are an equal number of steam and water pistons, providing the necessary synergy for effective operation. This design is vital for maintaining hydraulic balance and ensuring sufficient water is supplied to the boiler system, which is critical for steam generation.