An Application Research On Narrow Pressure Window Cementing Technology In South Ⅱ-Area

Cementing is an important link in the process of drilling and completion operations, directly related to the level of the quality of wells, the wells’ life and production of wells. DaQing oil-field southⅡarea depth is generally between 1500 and 1800 m, complete the drilling depth between 1750 and 1850 m, and present the deeply buried, thin reservoir, poor physical properties and other characteristics, puts forward strict requirements for protect reservoir in the process of cementing. Besides Putaohua oil layer fracture pressure is low, and the pore pressure is relatively high, so, is easy to happen lost circulation in cementing, and hard to pressure stability in cement curing process, and requirements disposable sealing above 1600 m, make cementing increases difficulty. So, the paper adopt the method is combine non-Newtonian fluid dynamics and non-Newtonian dynamics of Fluids in Porous Media, establish the new model for the borehole lost circulation formation and the lost circulation pressure calculation, solves the problems of calculation about lost circulation information parameter. Put forward the concept and characteristics of narrow pressure window, established a method to determine the pressure window, and determine the narrow pressure window of given the oil area, select the cement slurry system and the plasma column is suitable for a given block, optimized cementing operation parameters. For prevent lost circulation and pressure stability of cementing construction provides a basis. Establish and apply the lost circulation and pressure stability dynamics analysis software Window to predict the safe pressure window in cementing for a given oil area. Predict and analysis of lost circulation information, and real time correction and dynamic simulation of the scene construction parameters. Implementation of the security of cementing construction under the condition of narrow pressure window.