Analysis on Corrosion Dissolution Process of Dissoluble Open - Hole Packers in Tahe Oilfield Well Completion

Abstract

The corrosion dissolution behaviour and influencing factors of 7000 series aluminum alloy dissoluble open - hole packers treated by electroless nickel plating and epoxy resin sealing in Tahe oilfield completion operation were analysed, and the fragments of dissoluble packers used for the first time was tested and analysed. Results showed that the well completion string configuration, wear during running in, medium in the well and high temperature and high pressure environment were the main factors prompting the rapid corrosion dissolution. Electroless nickel plating coating had certain protective effect on body, however,it brought the galvanic corrosion as well. Besides, the 7A04 aluminum alloy body and nickel plated aluminum alloy coupon were tested under simulated field conditions, and the corrosion rates in different media were obtained, which provided a basis for the prediction of the service life of aluminum alloy body and the optimization of coating thickness.

Keywords

• open - hole packer|7000 series aluminum alloy|electroless nickel plating+epoxy resin sealing|acid fracturing|corrosion|well completion