Development and Application of Self-Sealing Compression Packer

In order to set down smoothly at intervals of a well with high deviation or wide variation of well track azimuth, and to protect casings from failure and optimize hydraulic jet pump drainage, a self-sealing compression packer was designed on the basis of rubber contact sealing theory and mechanical strength verification of the rigid parts. Based on the theoretical calculation of contact stress between the rubber cylinder and the casing wall, a physical experiment was conducted on the packer in terms of its resistance to a pressure differential at 170 ℃. In addition, a series of tests were carried out on site, including packer setting, hydraulic fracturing and hydraulic jet pump drainage. Theoretical calculations indicated that the minimum setting pressure of the rubber cylinder would be higher than 4.36 MPa, and the contact stress between the rubber and the cylinder would increase linearly with the increase of pressure differential after the packer is set down. It is indicated from the physical experiment that the rubber cylinder can withstand reverse pressure difference of 35.00 MPa at the setting pressure of 10.00 MPa and the packer can withstand the positive pressure difference of 70.00 MPa and reverse pressure difference of 50.00 MPa under 170 ℃. Field tests demonstrated that the packer can be set and unset smoothly, and used in hydraulic fracturing and drainage in wells with deviation of 72.4°. Compared with a traditional packer, the self-sealing compression packer can solve the problem of setting down smoothly at the interval with high deviation or wide variation of well track azimuthin order to protect the casing from fracturing and achieve hydraulic jet pump drainage.Field tests showed good application results and worthy of wide application in the fields.