Law Of Re-fracturing On Old Fracture Non-damaging Technology In Sand Formation

Re-fracturing technology is an important measure for higher yields in sand formation.Old Fracture Non-damaging Technology not only effectively seal the old fracture,but also reverse the original production capacity of the old fracture.However,this technique is used for the non-solid fluid,and its performance evaluation method and Law of Refracturing are different from that of conventional diverging agents.Based on the fracture evaluation method proposed by other scholar,summarized a set of new evaluation method taking full consideration of rock brittleness,fracture toughness and mesh density.It provides a basis for preliminary evaluation of fracability of sand formation.The experiments made clear that the Fuzzy ball has the characteristics of easy cracking,good surface degradation,good effect of reservoir protection and good sealing ability,and meets the requirement of repeated fracturing of sandstone.All results showed that Fuzzy ball can meet the demands of re-fracturing in sand formation.Through the true three axis simulation,it is found that there is a critical stress difference in the fracture steering.If the horizontal stress difference is too large,the crack steering can not be realized.The angle size of the crack is proportional to the dosage of the steering agent.The greater the injection amount is,the greater the stress redirection area is,the greater the steering angle.