The Mechanical Study Of Testing String In DeepWell

With the development of oil industry exploitation, depth-drilled isdeeper and deeper, and the bottom hole situation is more complicated thanbefore. The association and the intensity of testing string that used in shallowwell can not meet the deep well testing requirement in the situation of hightemperature and pressure, and have strongly affected the discovery andevaluation of the deep reservoirs. In view of the situation, it is stronglyneeded to study the mechanics on deep well testing string. This paperanalyzes the composition characteristic and operating principle of deep welltesting string. Considering the high temperature and pressure in deep well,the multiphase flow distribution method is studyed, the deliverability of welland the distribution of the borehole pressure and temperature are predicted.The alteration of temperature and pressure produces four actions, such aspiston effect, helical buckling effect, ballooning effect and temperature effect.The affection of testing string force and deformation that caused by the fouractions is also studyed. On the basis of the study above, the string depth,string loading, string intensity and string deformation are analyzed, the deepwell testing string mechanical model is built and the software is alsodeveloped. Using the software, more than 20 wells are designed and analyzed,for example, Jie 207 well and Fengshen 1 well are studyed detailedly in thepaper. The result of practical application proves that the design is up to themustard. The deep well testing string mechanical model analyzes the stringforce correctly in the process of the work. It is strongly enhanced the testingeffect and it is also speeded up the development of exploration activity in thefuture.