Sealing performance analysis and structure optimization of metal expandable packer

Abstract Packer is an important tool to ensure the success of fracturing. In the development of dry rock wells and ultra-deep wells, higher requirements are put forward for the temperature and pressure resistance of packers. Therefore, this paper provides a structural design scheme of metal expansion packers. The finite element software is used to simulate the sealing performance of packers under different working conditions and optimize their structural dimensions. The results show that the MEP with an outer diameter of 104 mm can achieve an effective sealing of about 300 mm in a sleeve with an inner diameter of 120 mm (expansion rate of 15.4%). The starting pressure of the tool is 23.4 MPa, the setting pressure is >42.3 MPa, and the recommended setting pressure is 65 MPa. MEP can also achieve good sealing conditions in sleeves with large expansion rate (≤25%) and large deformation (ellipticity ≤1.083). When the tooth height of the metal tooth on the metal sealing cylinder is 2 mm, the tooth width is 2.5 mm, the tooth bevel angle is 60°, the trapezoidal rubber ring is selected, and the ring height is 5 mm, the sealing effect of MEP is the best. After optimization, the circumferential minimum contact stress of the metal tooth can reach 716.7 MPa, which is increased by 62.7%. The average contact stress of the rubber ring is about 20 MPa, which is increased by 42.9%, which is suitable for high pressure and short time sealing requirements.