cement flows downwardly through cementing string 96 the interior of liner 28 filling the well bore below liner 28 the cement then flows upwardly through the annulus surrounding liner 28 then through ports 110 and 112 the annular space 106 and out check valve 108 in cementing the plug 120 is pumped down following the cement and seats in the lower end of the liner 28 the bypass flow of cement around the sealing cup assembly 70 assures that the liner is not lifted sufficiently to unset the hanger assembly 74 the drilling apparatus including the drill bit 14 and the three stage underreamers 16 18 and 20 are disclosed in greater detail in fig4 6 and 7 in fig4 a and 4b the upper end of the drilling apparatus is shown including the connection to the mud motor 21 and the telescoping joint 122 the joint 122 includes the sub 124 the outer tubular member 126 the inner mandrel 128 and the sleeve 130 the sleeve 130 is slidable axially relative to and in the space between tubular member 126 and mandrel 128 as shown in fig5 the sleeve 130 is provided with splines 132 which engage within the grooves 134 in outer tubular member 126 each of the splines 132 is protected by the wear inserts 136 positioned on both sides of the splines 132 as shown the body 138 of the underreamers is connected to the lower.