ROTATING BLOWOUT PREVENTOR WITH RIGID WASHPIPE

摘要

ROTATING BLOWOUT PREVENTOR WITHRIGID WASHPIPEABSTRACT OF THE INVENTIONA rotating blowout preventor of simplified construc-tion which requires no kelly drive bushing, and which has arotating external housing formed at the upper marginal endthereof within which the main bearings and seals are isolated.The external housing rotates about a fixed washpipe and sup-ports a stripper seal doughnut to which a stripper seal ismounted in underlying relationship thereto. A removal clampenables the doughnut and stripper rubber to be lifted free ofthe assembly for service or replacement. The bearing housingis fabricated in a manner to enable servicing the seals andbearings thereof without removing the blowout preventor fromthe top of a tool string. The bearing housing and seals there-fore are arranged respective to the rotating stripper rubbersuch that should leakage across the stripper rubber and sealoccur, the isolated bearing housing will be maintained free ofcontamination therefrom.- 1 -