Research In System Of Low Densitycontrol Fluid Of Gas Well In Honggang Area

Now there are many kinds of well control fluid in manufacturing of oil well, but the well control fluid which is aimed at low-pressure area and specific gravity is smaller than one does not consider filtration property. When working, organic molecule or water will invade reservoir bed, it can create pollution and arise reduction of output seriously.In Honggang block of Jilin oil field the pressure coefficient is smaller than one,down hole temperature is 40℃, so the well control fluid which is fit for Hong Gang block of Jilin oil field has to possess low density and low filtration.This paper through combining the basic characteristics of gas reservoirs in Honggang, evaluates the sensitivity of reservoir bed,by means of analysing drill core and cast, sums up the sensitivity of reservoir bed,obtains design philosophy of control fluid system.Studied on system of control fluid based on water water external emulsion,selected emulsifing agent, antiswelling agent, anchoring agent, fluid loss agent and so on, took filter loss and viscosity of control fluid to the standard, ascertained the best addition agent of control fluid, Through conditioning the proportion of oil and water, optimizing dosage of addition agent, obtained different density dispensation of control fluid system.Interior through measuring control fluid system gas cutting resistance, subside stability,re- servoir damageand so on,evaluates overall performance and capability about protecting reser- voir of control fluid system.