Most of Mexico south land operations require high mud density to control bottom hole pressures (from 15 to 17.3 ppg). This application becomes even more difficult due to a non-conventional borehole pressure profile. Severe mud losses could occur at shallow depths and formation inflow at deeper depths or vice versa. With that scenario in place, many different drilling techniques are required in order to reach the total depth, such as MPD (Managed Pressure Drilling), DSI PBL® Bypass System, and ECD control, which are used to allow drilling these very challenging oil wells.
The PBL® Bypass System has been used in many wells to control severe mud losses. The standard (Ertalyte or Torlon) activation balls has a SG of 11.6 ppg, so in heavier mud weights the floating factor makes it more difficult for the activation ball to reach the ball seat. For this scenario, DSI offers two solutions to mitigate this effect, that is the Fast Dart (SG of 64 ppg) or Fast Ball (SG of 21 ppg), and the selection of the ideal activating system will depend on the well conditions and geometry in order to achieve the optimal results.
The Fast Dart and Fast Ball have consistently helped to reduce mud loss control time and volume at heavy mud weight applications. Usage of the DSI PBL® Bypass system is vital to reach total depth at abnormal borehole pressure profile in conjunction with many other innovative drilling techniques in Mexico.