This paper presents the results derived from the research, whose first results were presented at AMPT 2005. At this conference, a new method for generation of rheological model to characterize non-conventional injection moulding by means of spiral mould was presented. The continuity of this research line has consisted of the development of several tests for validation of the rheological model obtained with the new method. Viscosity of a PEHD with different percentages of recycled has been tested, by means of several kinds of rheometers, like capillary rheometer and rotational rheometer, and the results has been compared to those obtained with the spiral mould. Conclusions of this research show the suitable parameters range, at which the results are comparable for the new method. On the other hand, another work line for the validation of the rheological models has begun, by applying the models to CAE injection moulding software, and checking the results by experimental trials with a industrial mould. This mould has been adapted to register pressure results during injection cycle. These trials take into account the influence of most of the injection process parameters, as well as different percentages of recycled.