Screw pumps typically employ angles of inclination of 30°, 35°, or 38°. When designed for higher lifting heads, usually exceeding 6.5 meters, a steeper 38° angle is preferred. Conversely, for lower heads and scenarios requiring high discharge capacity, a shallower 30° angle is typically chosen.
Generally, at a fixed capacity and lifting head, a screw pump with a 30° inclination will have a smaller diameter and longer length compared to one with a 38° inclination. This correlation between angle and dimensions is crucial in pump design and selection.
To increase a screw pump’s discharge capacity, opting for a larger number of flights is effective. However, two-flight screw pumps often present a more economical choice than three-flight pumps due to superior efficiency and reduced manufacturing costs. Besides the number of flights, the screw pump’s diameter also plays a significant role in determining discharge capacity. Currently, the market offers a wide range of sizes, spanning from 300mm to 5000mm in diameter.