The pipeline Robots have several purposes during the travel into the pipes, some of them are: maintenance, cleaning, removal of liquids, separation of products and inspection, among others. In these tasks the processes demands the evaluation of different operational parameters such as: maximum pressures, robot speed and vapor pressure, these parameters should be consider during the planning stage and is necessary to keep in certain limits during its operation. This paper aims to present the review of robotic systems used for pipes, and the simulations of movement of a robot into the flow have in consideration: Operation pressure, pipeline properties, fluid properties, and physical constrains of a typical pipeline Inspection Gauge (PIG), finally, shows the simulation results of the interaction between the PIG, the pipeline and fluid solved by difference finite method.