The Research Of Exploitation Formation Damage Mechanism And Evaluation

During the long-term production in the oil field, the exploitation formation could be damaged among the total production program.The essence of damages to the exploitation formations is the increase of fluid resistance and the decrease of permeability.The phenomenon is that the fluid can't flow out of or be pushed into formations.It's immediate result is the decreases of off-take potential and economic losses.However the damages to the exploitation formations are very common.The problem is getting more and more attentions to because of the big economic losses.The reasons of damages to the exploitation formations are complicated and indeterminate.This paper is focused on the mechanisms of the damages to the exploitation formations .degree of the damages and countermeasures to them.The paper analyses internal and external causes of the damages in detail.And mathematics modeling are done from the migration of the fine particles, stress around the borehole and the process of water injection.At the same time , overall evaluation to the degree of damages is done through theories and methods of fuzzy mathematics.The paper gives some countermeasures in drilling, cementing and oil recovery in steam injection aiming at the truth of thick oil petroleum deposit in Liaohe Oil Field on the basis of overall evaluation to the degree of damages and mathematics modeling to the mechanisms of the damages. Finally it makes software of diagnose and countermeasure to damages. The research and outcome is not only a guidance to the protection to exploitation formation, but also practical in site.