The lower limit of flowing pressure at various oil-gas ratio and water-cut stage in Wenwu Area is calculated using former soviet Craynof's rising theory formula of upright flow of oil and gas.

At present, large part of oil field has gone into the medium-latter stage, the pressure of oil-gas well has been lower year after year, pouring and producing contradiction change into intensify.

After almost 20 years of development, lower Interval of Du66 block has come to a later stage of steam stimulation, with the formation pressure lower and the steam stimulation effects poorer.