摘要 |
A multistage pump (4) comprises DEG a plurality of components (50, 60, 70, 80, 90, 100, 110) comprising a plurality of pre-assembled pump modules (70, 90, 110) including at least one twin screw pump module (1, 2), characterised in that the multistage pump (4) further comprises an elongate sleeve (41) for housing the components (50, 60, 70, 80, 90, 100, 110); and securing means (42a, 42b) attachable or engagable with a portion of the elongate sleeve (41), the securing means (42a, 42b) being operable to fixedly retain the components (50, 60, 70, 80, 90, 100, 110) within the sleeve (41). |