Study On The Mechanism,Inspection And Prediction Of Casing Damage

Oil gas output, injection effectiveness and service life of production and injection well are directlyaffected by casing deformation and damages, such as outside force, chemical corrosion and so on. With thenumber of casing damage wells increasing year by year in each oil field, inspections and precautions of casingdamage status have become more and more important during development of the filed. This paper systematicallyanalyzes the reasons of casing damage and introduce several advanced inspection methods, And introduce themethods of engineering logging which are used to inspect the cased hole status. Mainly analyzed are theapplications in inspecting casing damages are guiding such operations as work over and more. Illustrated are thevital functions of engineering logging in precautions and prediction of casing damages.The fast and slow flexural wave crossover phenomenon in anisotropic formation caused by uneven in-situstress is used as theoretical bases. A continuous phase spectral method for extracting phase slowness dispersioncurve is introduced. The method is deployed to process the crossed dipole data, thus to identify the types ofanisotropies from the dispersion characters of fast and slow flexural waves, those types include:â‘ the coincidenceof dispersion curves of anisotropic formation;â‘¡the parallel of dispersion curves of inherent anisotropic formation;â‘¢the crossover of dispersion curves of stress induced anisotropic formation. Given is a practical field applicationof cross-dipole acoustic measurements in estimating formation stress in Daqing Oilfield.In casing damages in the area 5 well time to the in-situ test data processing, altogether discovered 10 intervalexist formation stress, 5 sections ofthesel were geological personnel's confirmed, the confirmation (has not denied)the section geology understanding quite is also fuzzy. In this foundation, using casing damages predictionsoftware carried on prediction analysis of the single well, the well stability coefficient which the computationobtained is smaller than 1, therefore circumferential borehole exist certain unusual stress, but the rock of a well isstable, could not create the casing damage temporarily.Next step will use the prediction result of a single well shear wave casing damage, the union geologytendency, the static material and other test material, will damage the reason and the trend of development to thenested domain carries on the multi-disciplinary generalized analyses...