2.The keystone slot is narrower on the outside surface of the pipe than on the inside. Slots formed
in this way have an inverted “V” cross-sectional area and are less prone to plugging because any particle passing
through the slot at the outside diameter (OD) of the pipe will continue to flow through, rather than lodging within the slot.
3.While the slotted liners are usually less costly than wire-wrapped screens, they have smaller inflow
areas and experience higher pressure drops during production.
4.Slotted liners also plug more readily than screens; they are used where well productivity is small and economics
cannot support the use of screens.