One of the most important parameters to obtain for the appropriate cement slurry is the bottom-hole temperature which will determine the type and amount of additives needed in the slurry to achieve the required properties. At present, a new technique has properties. At present, a new technique has been developed to determine the bottom hole circulating temperatures based on data gathered with elactronical tools.
Field application has produced very reliable data that one can use to calculate the required BHCT that a cement slurry will encounter.
With the application of this technology the slurry designs have been improved, and the costs have been reduced to about 27% for the production liners and 38% for the production casings. production casings
As the oil wells are drilled to greater depths, new technologies have to be applied in order to obtain more efficient mechanical completions.
One of the most important advantages gained is the sucess of the primary cementing job on the production casing.
The most important factor in the design of the cement slurry is the circulating temperature, because an over estimation of this temperature will lead to the excessive use of some additives, and could produce over retarded slurries.
The BHST has been estimated through the use of temperature gradient maps, the application of correction factors to the electric log temperature and in some cases, when the wells stayed a certain amount of time in static conditions, the electric log temperature was used as the design temperature. This paper is to show the procedures Bloque III using informations obtained from the electric logs and electronical tool.
Initially the cement slurries designs for the production liner used the electrical log temperature as the design temperature.
This temperature was considered very close to the BHST because of the time transcurred since the last circulation until the moment the electric logs were taken.
This made slurries design with a high concentration of additives which produced an over retarded condition in the thickening time over the entire cemented interval, this lead to: higher W.O.C. time, difficult resolution of the evaluation logs and higher operational costs.