How can displacement control for a screw compressor be achieved?

Displacement control in a screw compressor is fundamentally about managing the volume of air or refrigerant that the compressor moves through its system. Turning valves is a common method for achieving this control. Specifically, by adjusting or modulating the valves, the flow or pressure can be regulated, effectively controlling the amount of displacement produced by the compressor at any given time. This can lead to increased efficiency, as the compressor does not need to work harder than necessary to meet demand.

While the other options may have their own merits in certain contexts, they do not directly address the specific means of displacement control within a screw compressor. Adjusting compressor speed can influence overall performance but doesn’t specifically control displacement in the same precise way. Using variable frequency drives can provide speed control and energy efficiency but again, it does not specifically manage the displacement. Installing larger motors may improve performance capability but does not directly relate to how displacement is controlled in the operation of the compressor. Turning valves, however, offers a direct approach to adjusting the displacement as needed, making it the correct choice.