Plastic casing for Hole Protection in Core Drilling

Abstract:

Plastic casing is used to protect borehole wall cooperating with steel casing at some shallow loose orcemented layers, that is,plastic casing,is put into use as exterior casing in upper part of hole and steel casing is still used as inner tube for isolating protection.It reduces cost,and accumulates experiences for treating comples for-matiors with plastic instead of steel.