Dissoluble degrading temporary blocking ball for temporarily blocking perforation blast hole and preparation method thereof

Abstract

The invention discloses a dissoluble degrading temporary blocking ball for a temporarily blocking perforation blast hole and a preparation method thereof, wherein the temporary blocking ball mainly consists of a dissoluble polymer casing and a spherical core body covered by the dissoluble polymer casing, wherein a forming material of the casing is polyvinyl alcohol or polycaprolactone; a forming material of the spherical core body is any one kind of materials from polyglycolic acid, polyvinyl alcohol, polylactic acid and poly (lactic-glycolic acid). The dissolution/degradation performance is good; no selection is needed on the dissolution/degradation water quality environment; the application range to the geographical environment and the temperature environment is wide; good pressure bearing intensity, good elastic deformation capability and good blast hole sealing performance are realized; the adaptation to the fracturing acidification temporarily blocking of an ordinary low-temperature oil gas well is realized; the fracturing acidification temporarily blocking technical requirements of high-temperature deep wells can also be effectively met; excellent flexibility and reliabilityare realized during the operation; the application prospects are good.

Description

Technical field [0001] The invention relates to a temporary plugging ball used in the process of fracturing and acidizing temporary plugging in oil and gas well exploitation, in particular to a soluble / degradable temporary plugging ball for temporary plugging of perforating blastholes, and a preparation method of the temporary plugging ball. Background technique [0002] In the production of oil and gas wells, with the continuous promotion of volumetric fracturing technology, the fracturing target layers of shale gas wells are becoming more and more complex. How to increase the leakage area through the complication of fractures, improve the effect of fracturing, and when the wellbore integrity problems caused by uncontrollable factors in the development of shale gas and the tools cannot be run for operation and construction, thereby affecting the production of oil and gas wells As a special layered fracturing technology, the crack temporary plugging diversion technology has incre...

AI Technical Summary

Problems solved by technology

The temporary plugging process of perforating blastholes usually uses plastic balls, rubber balls, nylon balls, wax balls, etc. as temporary plugging balls. These temporary plugging balls have the following main technical problems in the temporary plugging process of perforating blastholes: plastic balls, Because rubber balls and nylon balls are difficult to dissolve, they will get stuck in the blasthole after deformation and block the passage of the blasthole, which will affect the flowback and oil and gas production in the later stage; although wax balls can be dissolved under certain temperature conditions, their compressive strength is relatively low. Low, unstable plugging, especially in the case of high formation fracture pressure, it is impossible to achieve effective temporary plugging and diversion under pressure

Although this technology discloses a high-strength, soluble temporary plugging ball, the magnesium alloy material selected for its forming is selective to the dissolution environment, and it needs to be dissolved at a relatively high ion concentration, and there will be residue after dissolution; in addition, the The technical temporary blocking ball has better rigidity, however, the blast hole it is used for plugging is irregular in size due to the high-speed sanding in the early stage. The amount of deformation is small, the sealing performance is poor, and the temporary blocking effect is poor