h and to which are secured upper and lower generally t shaped members 12 and 14 respectively members 12 and 14 partially encircle and are secured to a socket shown generally as 16 socket 16 has a first upper frustoconical wall 18 and a second lower generally frustoconical wall 20 frustoconical wall 20 terminating in a radially inwardly extending lip 22 as best seen in fig2 members 12 14 and socket 16 do not form full annular structures but rather collectively define a laterally opening slot 24 framed by a pair of guide plates 26 and 28 received in socket 16 is a portion of a riser assembly shown generally as r riser assembly r comprises a section of steel piping 32 that is connected to the top deck not shown of platform p steel piping 32 is connected via a flange connection 34 to a titanium stress joint 36 which in turn is connected to a steel catenary riser 38 that extends to a subsea wellhead not shown as best seen with reference to fig3 a removable clamshell type bushing 28 surrounds stress joint 36 bushing 28 also has an inwardly facing frustoconical surface 30 because of slot 24 it will be seen that the stress joint 36 carrying bushing 28 can be easily inserted into the socket 16 and once positioned will be prevented from any downward axial movement bushing.