FIELD: oil-and-gas industry.
SUBSTANCE: invention relates to well drilling equipment including rotary exit preventer comprising body and bearing assembly. Bearing assembly comprises outer bushing interacting with adjacent casing surface, inner bushing, bearings and preloading element. Outer bushing has central bore while inner bushing is fitted inside said central bore and can be withdrawn therefrom. Bearings are jointed between said bushings to allow their concentric arrangement and relative rotation. First of said bearings takes up radial loads applied in between said bushings while second bearings takes up loads applied in lengthwise direction between said bushings. Preloading element maintains load at second bearing and said bushings to preload the bearing taking up lengthwise load.
EFFECT: stable operation at variable loads.
7 cl, 18 dwg
