Abstract: A method of construction of a well screen comprising the steps of providing a base pipe: spiral winding an inner drainage layer around the base pipe; spiral winding a filter layer around the inner drainage layer, then; spiral winding an outer drainage layer around the filter layer. Also disclosed is a well screen, comprising: a base pipe; a spiral-wound inner drainage layer disposed around the base pipe; a spiral-wound filter layer disposed around the inner drainage layer; and a spiral-wound outer drainage layer disposed around the filter layer.

Abstract: An inflow control device for a well screen comprising: a body having an internal bore, said body mountable in line with a base pipe of said well screen; a plurality of body apertures in a wall of said body, said apertures spaced longitudinally and circumferentially from each other, about said wall; a slide member in sliding engagement with an inner surface of said body, said slide member having a plurality of slide apertures; wherein the inflow control device is arranged to selectively and progressively increase the aperture area through the body through sliding the slide member, so as to align at least one of the body apertures with at least one of the slide apertures.