SUCKER ROD Russian patent published in 2008 - IPC F04B47/00 E21B17/00 

FIELD: oil and gas production industry.

SUBSTANCE: invention is related to oil production industry, i.e. to hardware to lift fluid from well and can be used to transfer motion as a part of sucker rod string from surface prime mover to downhole rod pump. Sucker rod includes hollow bar. The hollow bar is provided from both ends with heads with at least one of the side equipped with connecting part with thread element. Hollow bar is equipped with thrust areas. Through hole of the hollow bar is provided with inner bar that is provided with end stops interacting with thrust areas of hollow bar which ends are fixed in rod heads by means of detachable or permanent connection. Design of sucker rod allows for maintaining serviceable condition in case of external surface damage but with serviceable redundant element.

EFFECT: increased survivability, longer service life and reliability of sucker rod.

1 dwg