Solid Expandable Tubular (SET) Technology is receiving a widespread use in the oil industry nowadays. This technology is essentially a down-hole cold working process consisting of expanding a solid tube by drawing a mandrel through it either mechanically or hydraulically. The hydraulic expansion requires a high back pressure to move the mandrel forward, which leads to a sudden release (pop-out) of the mandrel towards the end of the process due to the stored elastic energy within the tube-fluid system. This sudden release results in axial and radial vibrations accompanied with stress and pressure waves propagating through the three mediums (inner and outer fluids and expanded tube). In the present paper, a mathematical model describing the dynamics of the three mediums has been developed. A specific case of a 127 mm tube in a 340 mm borehole with fluids of different properties inside and outside the tube was considered. The coupling effect describing the fluid-structure interaction resulted in modifications of the waves speeds and frequencies as compared to uncoupled solutions. The study also focused on the effects of stress and fluid pressure waves on the structural integrity of the expanded tube. It was noticed that the maximum vibration occurs at the free end of the tube. In addition, the model identified potential locations along the tube, which may experience collapse.

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