Abstract
Well cementing operations in south Texas tend to present a number of challenges to those responsible for constructing oil and gas wells. For instance, the temperatures and pressures at which the cement needs to be placed can be extreme, routinely exceeding bottomhole static temperatures of 300°F and pore pressures requiring fluid densities of 17 lbm/gal or greater to maintain well control. These extreme conditions can present challenges not only during placement of the cement slurry in the wellbore, but also later to the set cement sheath during the life of the well.
To effectively meet these challenges, well operators in south Texas have been using high-density cements that have been mechanically modified so the set cement will be more elastic and resilient. Advanced diagnostic software is used to predict well situations where these cements are required.
Currently, high-density elastic cements (HDEC) have been placed in more than 40 wells in southern Texas and the use of these sealants combined with diagnostic software has become routine.
This paper discusses the challenges presented when cementing high-temperature, high-pressure (HTHP) wells in south Texas, then details the successful best practice life-of-the-well solutions that have been applied by highlighting two representative examples.
The purpose of this paper is to help assist those tasked with the construction of HTHP wells to achieve their objectives safely and reliably and deliver zonal isolation that can be expected to last for the life of the well.
