Research On Key Technologies For "factory-based" Drilling Of Tight Oil Horizontal Wells

The estimated resources of the upper and lower dessert bodies of the Permian Lucaogou Formation in Jimusar Sag,Junggar Basin are 1.63 billion tons,which shows that the area has great exploration and development potential.However,the overburden permeability is generally less than 0.1 mD,the crude oil viscosity is large,and the oil wells have no natural productivity.Previous exploration well tests show that the use of conventional technology has high investment,low single well production and can not achieve effective tight oil.Development.Successful development experience of tight oil in Bacon Oilfield shows that large-scale fracturing technology of horizontal wells with long horizontal interval and "factory"operation mode are effective ways to solve this problem.In view of the characteristics of compact oil in Jimusar sag and drawing lessons from foreign experience,with the idea of "unconventional concept and unconventional technology”and around the low-cost strategy,the research on Key Technologies of "factory" drilling,optimization technology of well bore structure,personalized PDC bit design and optimization technology,three-dimensional trajectory optimization design and control technology and pilot test of 10 wells are carried out.Through testing,a series of matching technologies for "factory" drilling have been formed.On the basis of the optimization model of "factory" drilling and completion platform in other areas,this paper designs a "factory" platform,which saves 58.33%of the wellbore area by a single platform;studies the matching technology of"factory" drilling for three-dimensional long horizontal wells,and studies the rapid movement of drilling rigs,batch drilling operation procedures,drilling fluid reuse,electric oil substitution for industrial network of electric drilling rigs,etc.The key technology of factory drilling.The drilling efficiency is increased by 21.34%,and the reuse rate of recovered drilling fluid is up to 70%.The multi-target trajectory design and control technology of three-dimensional horizontal wells with the core of "space arc design,sectional control azimuth,optimizing drilling mode and adjusting target while drilling" are studied.The maximum offset is 265 m,the maximum horizontal displacement is 2312.4 m,and the maximum length of horizontal section is 2060 M.The safe drilling of the 2 900 m open hole section and the 2060 m horizontal section of five series of formations is realized;the average mechanical drilling speed is higher than that of earlier exploration wells.It increased by 233.8%,completed a new record of 1410m horizontal section for a single domestic PDC bit,shortened the drilling time by 74-100d,and greatly reduced the development cost.The "factory" drilling technology of long horizontal section horizontal wells has produced enormous economic and social benefits.Through the "factory" platform operation,the cost of land requisition for wellsite and road is reduced,and the destruction of surface vegetation is reduced.The drilling fluid is reused more than 1400 m3,which saves the cost of drilling fluid,reduces the consumption of water resources and waste discharge,and reduces the environmental pollution.Experiments show that the "factory" horizontal well drilling technology is an effective means to achieve tight oil development,which can provide reference for the effective development of other unconventional and low permeability reservoirs,and has a high popularization prospect.