[en] Incrustation in pipelines found in oil exploration facilities - a problem that has been related since the '30s - reduce the flow and, as a consequence, the efficiency of the plant, thus impairing the activities of exploration and production of oil. These incrustations occur when there is mixing between water from the formation of the wells and the sea water injected in them - an injection which aims to increase the capacity of lifting and removal of the oil trapped in reservoirs. The purpose of this work is the development and application of the technique of gamma transmission to detect incrustations in pipelines for prospecting of oil. The measurements were performed using a system composed of Cs-137 source and NaI(Tl) scintillator detector. The results were processed in a spreadsheet for calculating the measurement of the thickness of the incrustation located in pipelines. The spreadsheet performs simulations of the interaction of radiation based on the known data of the pipe, such as diameter, thickness and composition, providing values of intensity that are compared with those obtained experimentally, and thus it is able to determine the existence and thickness of an infiltration layer. For the validation of both the simulation and the system, some laboratory tests were performed with a sample of pipe containing parts with and without incrustation. The results showed that, despite the limitations, the system was efficient enough to detect incrustations, showing the advantage of the reduced dose which is of great importance in offshore environments. (author)