Fine Mpd Downhole Pressure Calculation Method

The main difficulty of drilling technical in Central Tarim which include overflow and leakage occurred in frequently; hydrogen sulfide in the reservoir is not well distribution; existing lots of crack. The solution of solve this problem is managed pressure drilling horizontal well. In conjunction of the features of increasing production of horizontal well and reducing reservoir damage, so managed pressure drilling horizontal well has be created.For the reasons of technical monopoly by foreign company and precision control pressure drilling critical equipment is lack in our country. unable to complete accurately controlled pressure drilling closed-loop control. As a solution that calculate the pressure in the wellbore to replace the pressure in measurement.If the pressure in the wellbore can be calculated in each situations and the result satisfy a certain precision. It means that the condition of substitute for measuring joint has been applied, which resolve the troubles that lack other equipment and independent implement precision managed pressure drilling.The purpose of article is explore one method for calculate pressure in the Central Tarim carbonate reservoir. It is necessary support for drilling to the implementation of accurately control pressure.What is the thesis mainly studied as follows:(1) The basic thought is that solve the drilling problem such as pressure sensitive, the high level of the hydrogen content, fracture development is MPD. The basic principles of the pressure control- The whole process of micro-excessive.(2) Makes detailed explanation about each operation process conditions by analysis control pressure drilling control system composition and function in the Halliburton company.(3) To measure of the 1.08 g/cm3 water-based drilling fluid density in high temperature and high pressure through high temperature and high pressure which is made by southwest petroleum university.(4) Through the establishment of accurate control pressure drilling physical model and mathematical model, adopt the theoretical analysis method to calculate all kinds of conditions pressure in order to implement MPD by accurate control basis.(5) It means that the research results satisfy the construction needs through compared with the calculation results and construction data. It is break through difficulties in the MPD, control pressure drilling technology laid a foundation...