Data interpretation in horizontal and highly deviated wells is difficult because fluid phases segregate, slug or re-circulate along the high angle section, often causing stratified flow. Conventional tools with sensors centralized in the wellbore only gauge flow properties in the middle of the wellbore and miss out what is happening in the circumference of the wellbore.
The Resistance Array Tool (RAT) and the Capacitance Array Tool (CAT) are tools with 12 miniature sensors mounted on collapsible bow springs. This design enables the sensors to intercept the fluid flowing along the circumference of the well bore, providing a more detailed picture of the flow regime and a more accurate PL interpretation. The software also generates the average hold-up for each phase.
The CAT is a 12-sensor fluid identification tool. Each sensor measures localised fluid capacitance and individual phase hold-up close to the wellbore. Different dielectric constants enable identification of oil, gas and water.
Service Name | CAT |
Length | 1310 mm / 51.43 in |
Weight | 8.1 kg / 17.3 lbs |
OD | 43 mm / 1.688 in |
Hold-up range | 0-45% water hold-up |
Maximum opening | 7 in casing |
Maximum pressure | 1030 bar / 15 000 psi |
Maximum temperature | 177 °C / 350 °F |