Abstract:
To solve the problem of sand production that occurs during oil and gas well exploitation, a new sand control method of filling perforation channels with a temperature-sensitive shape-memory polymer was proposed with the goals of simplifying the construction procedure, reducing sand control cost, and prolonging the effective period of sand control. Shape-memory polyurethane foam was selected as the raw material, processed into irregular particles of 3–6 mm in particle size, then coated with epoxy resin and curing agents on the outer surface. A sand control material of swelling particles was thus prepared, and its swelling performance, temperature resistance, compressive strength, flow performance, sand retention, and medium resistance were evaluated by testing. The results showed that this sand control material started to swell at the temperature of 60–70 °C and its maximum adaptive temperature was 90 °C. With a swelling coefficient of 200%, this material could form a monolithic sand retention barrier after it swelled and cemented in a confined space. The barrier exhibited a compressive strength of 4.5 MPa and a permeability of 90 D. It is capable of retaining formation sand above 0.15 mm in particle size. The flow performance and anti-clogging ability of the proposed material were significantly superior to those of the sand control material of resin-coated sand. The proposed sand control material deserves promotion and application because the sand retention barrier it forms when applied to sand control is highly permeable, high-strength, and anti-clogging, and sand control with this material has the advantages of low cost, simple construction, and leaving no strings.