T-nets are constructed on the basis of experience gathered during experiments performed on the flow models of production systems [1, 4 and 6-12] and experience from colored Petri nets simulations. Transforming net is functioning in an asynchronous manner due to the initiation of transformers in specific periods of time. Possibilities to time-flow tasks are imminent features of T-nets - resources are gathered in the accumulators; resource transformations are described by the transformers. Task decomposition and task result synthesis is performed in a continuous manner. T-net plays the role of virtual model of real task realization processes. The existence of such model allows to monitor and asses the progress of realized tasks as well as calculations and simulation of task realization strategy.