Prediction Method Research Of ECD Applied To Dabei And Keshen Blocks

The Dabei and Keshen oilfield are locatede at the foot of the mountains.The temperature of this area can reach 180?,and the pressure can reach 140 Mpa.At the same time,the safe range of drilling mud density is very nerrow.The properties of drilling mud would have some changes inevitablely under this condition.For the reason of narrow safe range of mud density,some complex accidents would happen.So it's very important to find a accurate calculation method which can be applied to calculate the pressure of the wellbore.The main work of this paper is to study the calculation method of ECD.Firstly,we should analyze the changing rule of rheological property of the drilling mud under the high temperature and high pressure condition.Then we can establish the related calculation modle.Also,we need to analyze the changing rules of drilling mud density under the same condition in this paper.Through the literature research,we evaluate the diffient methods and give the best calculation method.In this area,the wellhole is straight.So we can analyze the temperature field of wellbore simply.The calculation method of ESD is mentioned at the same time in my paper.To calculate the perssure loss,we give the generalized flow index method which is very accurate.At last,we select some wells of Dabei and Keshen oifield,then calculate ECD of these wells and give the corresponding evaluation.