As drilling techniques advance and wellbores become more complex, placing successful cement plugs downhole on the first attempt becomes more challenging. Phenomena and well conditions can have a negative influence on the performance of the cement plug, significantly impacting drilling time and costs. When plug-cementing operations are required in an updip hole section, the following concerns become even more difficult to address:

  • Boycott or extrusion effects, especially in highly deviated wells.

  • Lost circulation problems caused by the narrow mud-weight window.

  • High concentrations of lost-circulation materials impede pumping at the desired rates for optimum displacement efficiency.

  • Shorter plug-length requirements, because reentries are becoming more popular in mature fields as an alternate way to look for different production zones.

  • Complex wellbore geometry.

  • Difficulty of effectively placing small volumes of slurry under deep, high-temperature conditions and washed-hole sections.

This paper documents a Middle East field application where an abandonment plug was required to be set in an uphole-downdip section of the wellbore. After several failed attempts using a conventional plug-setting aid, an application-specific plug-setting aid was designed that incorporated torque-capability to help enable the workstring to be run in hole (RIH) in an updip wellbore and an annular isolation element to prevent slurry fallback in the uphole-downdip hole section. Detailed customer expectations and performance criteria will be provided, resulting in a conventional plug-setting aid that was successfully retooled to enable slurry placement in an uphole-downdip wellbore.

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