Fluid flow significantly determine cutting and welding processes. When cutting, the quality of the cutting free water jet is decisive for the cutting outcome. While welding, the quality of the shielding gas flow determines welding seam irregularities, such as pores, tempering colours, as well as the flow tendency and properties of the molten metal. Therefore, at OSCAR PLT, we use efficient flow visualisation methods for designing welding heads, and optimizing process, as well. The test benches are designed for mobile applications. Therefore, they can be used in the manufacturing environment at the customer’s premises or at the partner’s test stations. The following methods are offered: streak measurement is an established method of flow analysis. Further developments in the field of illumination, optical design and camera technology enable us today to take images of great quality. To compress information, statistical information is generated from image sequences in the post-processing stage, and the structures in the images are purposefully withdrawn from mean values. Our expertise ensures the analysis results, from the measurement setup to evaluation and discussion of results. The oxygen measurement is used in the spatially resolved determination of the shielding gas cover and is particularly relevant in qualifying welding torches and laser processing heads. In contrast to the streak measurement, it enables quantitative results via a measuring surface (2D plot) or the radius (line scan) of the shielding gas nozzle. In principle, this method is applicable with or without electric arc.