Preparation And Application Of A New Type Of Downhole Excitation Source

In recent years,oil exploitation is increasing day by day,and shallow oil reserves are seriously insufficient,so it is urgent to go deeper for deep exploration.Currently,some researches only carry out exploration in shallow layer or surface,and there are few researches on deep well environment.As a result,the new downhole excitation source can withstand high temperature and pressure,generate enough energy to protect the oil steel well pipe,and obtain high-resolution maps.In this study,through theoretical analysis and performance testing methods,different explosive formulations were evaluated and optimized for detonation velocity and sensitivity,and the optimized explosive formulations were tested for shell source,sieve source and blind hole source through ground test.On the basis of this explosive,the shell charge shell,the diameter of the charge,the porosity of sieve source,and the porosity of shell source were analyzed.Discussion and analysis on the effect of blind hole source charge,and finally test in the field environment.The results show that:(1)The explosive formula with low detonation speed and low sensitivity and the addition of an appropriate amount of Al powder can effectively enhance the resolution of the atlas,and the normal initiation under high temperature and pressure environment,that is,the formula of70% RDX,15% potassium nitrate,10% aluminum powder,2.5% paraffin,2% liquid silicone and 0.5% graphite is adopted.(2)under the condition of no in-situ stress protection,the charging diameter of 20 mm can provide enough energy.The oil steel casing and concrete casing on the outside of shell source and screen source are seriously damaged,but the damage degree is similar,while the effect of different charging amounts of blind hole source is not obvious,and the oil steel casing and concrete casing on the outside are not damaged.It indicates that the energy generated is low and therefore does not meet the exploration requirements.(3)According to the ground test of the screen porosity,the expansion rate of the screen with a 15 mm aperture and a porosity of 7.7% is about 5%;With a 10 mm aperture and a porosity of 13.3%,the expansion rate of the screen is about 7%.Therefore,the method of large aperture and low porosity can reduce the expansion diameter of the screen,effectively protect the petroleum steel casing and pull out of it successfully to recover the fragments.(4)In the actual environment,the sieve source has been verified and can recover the fragments generated by the explosion,effectively prevent pipe clogging,and has application value.