Published on 4 July 2018
Successful Zonal isolation with Saltel Steel AZIP
Annulus Zonal Isolation of the upper reservoir to increase the well production from the lower reservoir in the Boscan field, Venezuela.
The well located in Boscan field, Venezuela, was designed to be completed as Stand Alone Screen (SAS), with open hole zonal isolation. The client uses Stand Alone Screen Completions in highly deviated wells to obtain higher productivity. When producing two zones in the upper and lower Boscan, separated by a shale zone, the client noticed most part of the water and fine migrations produced were generated from the Upper Boscan and the shale zone. A zonal isolation packer was requested to isolate the rest of the upper reservoir (upper Boscan) and produce only from the lower Boscan.
The openhole packer selected was a 51-2in Annular Zonal Isolation Packer (AZIP-C 0-1), crimped onto the casing, with a pressure compensation valve to cut the communication between the packer and the casing, while opening a communication between the annulus (lower boscan) and the packer, once expanded.
Once installed below the shale, the AZIP would increase the production, and reverse the decline of the field production (Campo Boscàn). Prior to proceeding to the AZIP installation, a Quantum packer had to be set first. Once the Quantum installed, the AZIP bladder expansion started. The packer was installed in ~40 min, with increasing pressure from 1,200 until 4,760 psi. At 4,500 psi the valve located in the inner side was closed and opened a communication with the annulus on the lower side of the Packer, equalizing the pressure. Everything went as per setting program.