The problem of technical condition identification of aging oil pipelines in Russian Federation and in the world is relevant, since a significant number of them have been in service for over 30 years. More and more of them are getting closer to running out of normative resources. Within a method for reducing the size of task of identifying the technical condition of oil pipelines there were created special types of multigraph models (MGM) with interval-valued states of geometric characteristic of metallic shell defects. Depending on oil pipelines operation time, the behavior of proposed models has been examined and operating performance with due account for technical condition identification has been determined, also the possibility of diminishing scope of inspections and repair works was shown. Multigraph models proposed here contain a set of states, which were singled out for the first time according to the analogue variable and are connected with multidirectional arcs with intensities of damage calculated on the relative amount of defects in the states. This approach greatly extends the functionality of graph models currently in use. The study of the oil pipelines found out that the use of multigraph models significantly reduced the magnitude of identification task by a factor of 21 to 38 times. Numerical solutions regarding probabilities of states, obtained for oil pipeline’s models, are sums of exponential functions that depend only on the intensities of damage. Probabilities of the states have an important physical meaning, as they relate to the amount of time spent in the corresponding states of a model. They exhibit a preferential location of object models as undesirable from the standpoint of their efficiency of functioning of the state. It was proposed to return the objects to their initial state through proper allocation of resources of an enterprise by changing the ratio of the intensities of damage. The generated information helps to build long-term schedules of repair works based not on the calendar principle, but on the amount of defects to be restored.