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In the bi-oriented film blowing process an extruded tube (denoted as primary tube) is re-heated and blown and stretched simultaneously, followed by forced convection cooling. The process is being progressively applied to a larger range of polymers and applications, which justified the in-house development of a laboratorial line. Operational parameters and construction features determine the thermo-mechanical conditions under which the bi-orientation occurs and, in turn, the final film properties. For example, practical experience has shown that an accurate control of the heating stage prior to bi-orientation is mandatory. Also, the rheological behaviour of the polymer(s) used is crucial, since both the feasibility of producing a stable bubble and the level of molecular orientation induced will depend essentially on the extensional behaviour and elasticity, respectively. In this study, the lab-scale prototype extrusion line is presented. The performance of its re-heating oven is characterised via monitoring the axial and circumferential temperature distributions with a thermographic camera, as well as the evolution in space and time of the surface temperature of thick plastics tubes mimicking the plastic film. A comparative study of the shear (oscillatory rheometry) and extensional properties (Rheotens) of materials that are often used in this technology is also presented, with a view to establish correlations between rheological response and processability. The aim is to be able to assess the adequacy of new candidate materials (e.g., biodegradable polymers) for this technology.