| As the 2nd largest gas field of Sinopec, Dainiu Gas Field has low natural deliverability before fracturing and its buried depth of gas seams is relatively great, though it has good pool-forming conditions for natural gas. DaiNiu Gas Field pertain to low pressure and low permeability. Aimed at the characteristics on margin gas bearing formation of low pressure and low permeability storage layer as the congenital defect of Daniu gas field , the use of extended reach horizontal well is very useful to increase discharge area and enhance control reserves of single well and gas production. This would also be helpful to reduce drawdown pressure, extend producing period and improve recovery rate of developed gas reservoir.The thesis conducts the analyses regarding the triaxial statics of navigation drilling system, bulids up mechanical model on the basis of differential equation method, completes the differential equation by using weighting residual value law, seeks for the solution on drill bit angle build-up force by employing the search procedure based on the target of minimal drill bit bending moment value,and handles guide drilling rig compound drilling state following the evaluation of hold angle capability connecting drilling rig compound drilling progress through applying the average angle build-up force in the changing process from the range 0°to 360°of tool face fixture angle. The author puts forward the thoughts of controlling core on single curved bistable guidance system by analysing mechanical property of single curved bistable guide drilling rig aimed at extended reach horizontal well path control of Daniu Gas Field.The drog and torque is an important research topic, the prediction and control is the key and difficulty of successfully. The thesis puts forwards the assumption concerning the contact of drill stem and borehole face at the location of the major drill stem diameter on drill adapter and centering device on the basis of making a comparative analysis of rationality and reliability for model for drag and torque calculation. Then the thesis addresses the idea of judging whether or not raising the new contact points based on whether the drill stem bending deflection between two contact points surpassing the interpace of drill stem and borehole face. And what's more, through the above discussion, we will obtain improving measures to figure out the positive pressure of different contact points.Based on above theory, I monitored the construction of Daping 4 Well successfully. This well is as long as 1624 m at horizontal depth, setting a record of the longest level section in Sinopec. This well also proved that we have the ability to carry out the well drilling of 1500m extended reach horizontal well with conventional equipment in our country. The agreement of measured value of Daping 4 Well friction torque and predictive value of improved conceptual model predictive value further testifies that practicability and correctness of the presented method. |