Puyang Junhong Rubber Co., Ltd.

Puyang Junhong Rubber Co., Ltd.

What are the causes of sucker rod fracture?

2021 09/29

In order to further improve the degree of recovery,the property of produced fluid changes,and the occurrence frequency of sucker rod fracture in pumping Wells also increases,which brings many difficulties to production management and increases the cost of crude oil.So what we need to know is what causes the sucker rod to break?
centralizer
(I)Description of macroscopic characteristics of sucker rod fracture

By analyzing the fracture sections of 21 ordinary rod Wells,the fracture sections can be divided into three zones,namely,corrosion fatigue source,extension zone and transient fracture zone.Corrosion fatigue source,under the action of alternating stress in the up and down stroke of sucker rod,the corrosion pit,scar or internal material defect on the surface of sucker rod centralizer is easy to form stress concentration,cause cracks and form corrosion fatigue source.

(2)Material of sucker rod

According to the standard of sucker rod,sample some broken rods,and test or test five physical and chemical properties including chemical composition,tensile properties,impact properties,hardness and metallographic microstructure.The results show that the material of the sucker rod for inspection is uniform tempered sorbitite,and the hardness,tensile properties and impact properties meet the requirements of the STANDARD for HL sucker rod.Therefore,the rupture of snap-rod centralizer has nothing to do with rod quality.