SUCKER ROD STRING Russian patent published in 2007 - IPC E21B17/05 

FIELD: oil production, drilling rods or pipes, flexible drill strings, kellies, drill collars, sucker rods, casings, tubings particularly operation of deflected wells with downhole sucker-rod pumps.

SUBSTANCE: sucker rod string comprises sucker rods, closed couplings and hinged couplings installed in deflected well areas and in lower string part. Hinged couplings are made as cups with inner boring and connection threads for rod receiving made in the first cup end. Fixedly connected to another cup end is split support bush. The bush has conical boring arranged inside cup at cup boring level. Half-rod with spherical head is installed in cup boring and is kinematically connected to conical boring of split support bush. Half-rod body is inserted in axial orifice of split support bush and is spaced designed radial distance therefrom. Half-rod and cup are mutually arranged so as to accommodate axial travel thereof and are provided with mating contours defining designed gap in transversal section and spaced apart a distance equal to travel reserve. As longitudinal compressing force appears in hinged couplings half-rod and cup creates fixed kinematical coupling providing torque transfer from one component to another one.

EFFECT: extended operational capabilities of sucker rod string.

3 dwg