APPARATUS FOR TENSION STRAIGHTENING OF RODS OF DEEP WELL PUMPS Russian patent published in 2003 - IPC

FIELD: equipment for making and repairing rods of deep well pumps, possibly in industry branches of petroleum machine engineering and in repairing shops of oil production plants for mechanized straightening of new and used pump rods. SUBSTANCE: apparatus includes mounted on frame power cylinder; movable and stationary clamps, each having tip provided with thread for joining with rod; motion pickup whose stem is joined with piston of power cylinder; pressure relay; distance counter and unit for controlling supply of working liquid to power cylinder. Apparatus is also provided with pressure meter connected to pipeline of power cylinder; comparator; devices for indicating and marking rods according to strength class. First and second inlets of comparator are connected respectively to outlets of pressure meter and distance counter. Devices for indicating and marking are connected to respective outlets of comparator. EFFECT: possibility for measuring averaged along cross section yield strength of rod metal and classifying rods by said value. 2 dwg