Screw pump (2) comprising: a casing (3) with an inlet (30), an outlet (31) and a flow chamber (32) between the inlet and the outlet; at least two screws (4, 5, 6) housed in the flow chamber to force a fluid flow through the flow chamber from the inlet to the outlet; and a flexible coupling (11) connected to one of the screws to couple the screw to a drive motor (10).

The disclosure relates to a screw pump (2) comprising: a casing (3) with an inlet (30), an outlet (31) and a flow chamber (32) between the inlet and the outlet; and at least two screws (4, 5, 6) housed in the flow chamber to 5 force a fluid flow through the flow chamber from the inlet to the outlet; wherein the casing (3) comprises a shell (33) within which an insert (34) defining the flow chamber is housed.