Overview

A well completion job is done in May. 2014 with Ruifeng Petrotech’s OTMZ (One Trip Multiple Zone) System, which is the first local completion tool of the category used by CNOOC in South China Sea.

Challenges & Solutions

The target well has 2 zones to be completed with gravel pack in 7” casing by design, a permanent sump packer is installed at the bottom of the well, then the completion string with screens, packers and service tool were run in hole and plugged into the permanent packer’s seal bore. The service tool is used to set the top packer and isolation packer of the bottom zone, through which the sand laden fluid is circulated to form a solid sand control barrier between screen and casing. After the packing of bottom zone is done, the service tool is then pulled up to the upper zone, to repeat the setting-packing process.

The sealing parts and the tool strength were two key factors to the success of one trip multi-zone tools, the integrity of the tool is challenged by abrasions from frequent movements, however, Ruifeng Petrotech’s OTMZ tool was proved to be robust enough for downhole environment. The application of OTMZ tool greatly enhanced customers efficiency of gravel pack operations.