workover patch vs casing perforations


Enhanced Oil Recovery

EOR, enhanced oil recovery

EOR (Enhanced Oil Recovery) helps improve the average recovery factor for typical mature fields around the world up to 30-40%, extending worldwide reserves to a bit more than 50 years supply of oil. The different techniques used, including Water & Gas injection (WAG), polymer flooding, flow diversion, the use of surfactants, and steam injection for heavy oil (both Steam Assisted Gravity drainage – SAGD wells, and Cyclic Steam Stimulation (CSS wells) will increase the life of a field. Sometimes oil and gas operators need to modify the injection/production profile, to switch from producer to an injector well, having first to cover unwanted perforations with a casing patch.

EOR to Isolate Perforations

Saltel Industries offers a remedial alternative in EOR to isolate perforations with a thin-walled casing patch. Run with drill-pipe or coiled-tubing, Saltel Patch allows one of the best ID access to the well below. (For packers, tubing anchors…). Therefore, Saltel Xpandable Steel Patch seals effectively and holds significant differential pressure ratings (See enhanced oil recovery patch).

Modifying injection profile

Many wells are completed and perforated, in both production and injection configurations. In other words, during the life of well, the required profile might need a reconfiguration. Fluid levels Might indeed vary, and EOR techniques allow modifying downhole parameters. As a result, it might be necessary to:

  • Close off existing perforations.
  • Re-perforate in new zones.
  • Change the injection profile.

Water shut off, gas shut off

Covering perforations with Xpandable Steel Patch is an optimized EOR technique. This Technique allows eliminate the unwanted and costly water production. Consequently the patch allows to reduce the gas production, and to avoid or alleviate at the same time any risk of cross-flow. (That is to say any risk of communication between 2 reservoirs). This technology is also suitable when converting a producing well into an injector (or vice-versa).