DOWNHOLE FORMATION FLUID PULSING TOOL TO MEASURE FORMATION PERMEABILITY, PRESSURE AND TAKE FLUID SAMPLES

摘要

The apparatus of the present invention relates to a down hole tool (A) capable of extraction of valid samples and making pressure measurements useful in calculating formation permeability. The tool incorporates the features of a straddle packer (P) to allow formation fluid specimens to be taken at large flow rates without depressing the pressure below the formation fluid bubble point. When used in combination with a pressure probe (46) the tool is used to obtain meaningful permeability readings in a larger radius area than previously permitted with known designs. Additionally, the apparatus of the present invention allows flow control during the creation of the pressure pulse which enhances extraction of valid samples and the permeability determination. The apparatus may be modularly constructed so that in a single descent of the tool, a pressure profile of the zone of interest can be made, a fluid analysis can be made at each station, multiple uncontaminated fluid samples can be withdrawn at pressures above the bubble point, local vertical and horizontal permeability measurements can be made at each station, a packer module can be set at a location dictated by previous measurements and a large scale pressure build up test can be performed.