Guided by the concept of 'reversible structure solution fracturing fluid'

a new type of thickening agent as well as a new fracturing fluid system with the agent is developed.Tests show that the system is a typical viscoelastic structure solution with it's G′ constantly bigger than G″;with a viscosity of merely 30mPa·s(170s

-1

)

the system has a proppant-carrying capacity strong enough for operation;this viscosity can be easily achieved at the temperature of 150℃ by adding only 0.8wt% of the agent into the system and is not sensitive to the shearing time;the system has a "clean" viscosity break fluid

high proppant flow conductivity(more than 90%)

and slight damage to core(lower than 10%).The application of the system in five wells

namely P65-9

Wen 99-20

Wei1 0-40

Weiche-214

and Wei 355-4

in Zhongyuan oil field

yields positive stimulation results and causes lesser damage to formations than that of conventional fracturing fluids.It is also user-friendly because of its simpler composition and preparation procedure

excellent proppant carrying capacity

small friction drag(22% of that of fresh water)

and higher working temperature(up to 120℃).