Matching Technology and Application of Gas Drilling in Daqing Oilfield

Gas drilling matching technology was researched and applied in Daqing Oilfield,in view of the problems of slow ROP in deep formation and difficult production in"low porosity,low permeability,and low salinity"shallow-medium reservoirs.According to monitoring of humidity and gas injection parameters with matched equipment,formation water identification,water production calculation,optimization of BHA and drilling parameters were carried out,and"inside spray and outside invasion"of gas liquid conversion was used to solve problems such as downhole complexity,well deviation,hole instability caused by water production,which form a set of matching technologies for gas drilling,fulfilling safe drilling in deep mud shale formation with water production.The application of this technology in 27 deep wells of Daqing Oilfield shows ROP is increased more than 4 times,and drilling cycle is decreased more than 15 days;while its application in 8 shallow wells results in a production increment of more than 2 t/d per well without stimulation.This proves gas drilling is suitable for improving drilling speed in deep layer,and shallow gas reservoir protection,serving as a new means for speeding up exploration and development in Daqing Oilfield.