The Reliability And Remainder Life Research Of Sucker Rod

Existing bar oil pumping method is a sort of artificial lift oil extraction method, which is the most abroadly applied .At present , during the every kind of artificial lift oil extraction methods , it is still the chief degree. The sucker rod is the important component of the existing bar pumping equipment. It passes beam pumping unit's dynamic force to oil well pump underground. The sucker rod's fatigue strength and its service life determined and effect the complete set of pumping equipment's maximum pumping depth and its delivery capacity .The oil pumping bolt is composed by couplings connected of decades or hundreds of sucker rods. During the oil recovery process, the oil pumping bolt bear the no symmetric load action .Its working medium is crude oil and ledge water. However, a lot of pumping well's tamegai liquid contains corrosive medium. So, the sucker rod's main failure modes are fatigue fracture and corrosion fatigue crack. Breaking and missing out accidents of the sucker rod strictly affect crude production rate, and add the workover fees, and enhance crude oil costs. For enhancing sucker rod's operational reliability and its service life. This paper applied reliability theory, fracture mechanics and experiments to study fracture failure problems. Starting with investigation and research for the production well histories of Taching oilfield, collects existing bar oil well's fault system, clear up and analyze data ,set up sucker rod systemic fault trees, and qualitatively and quantitatively analyses the fault trees,find out weaklink during the sucker rod's serving period. Aiming at the weaklink, adopt experimental for the sucker rod's material and its component give out calculating methods of stress intensity factor and fracture toughness etc, afford theoretical bases to the calculation of the reminder life. By the study for sucker rod material's fatigue crack growth disciplinarian afford reliable foundation for sucker rod remainder life. Applied fracture mechanics and reliability theories to calculate its remainder life and reliability, afford theoretical basis for establishment of the sucker rod's serving period and repairing period.