7 Mixing machines, in particular static mixers for industrial purposes; mixing machines, namely, static mixers for low-viscosity or gaseous fluids for industrial purposes; mixing machines, namely, static mixers for homogenising, dispersing, emulsifying and suspending fluid substances for industrial purposes; mixing machines, namely, static mixers for incorporating gases, gas-liquid mixtures or liquids in a gaseous stream for industrial purposes; mixing machines, namely, static mixers for turbulent streams for industrial purposes; mixing machines, namely, static mixers for flue gas purification and for flue gas purification installations for industrial purposes; mixing machines, namely, static mixers for mass transfer for industrial purposes; mixing elements, components, accessories and spare parts for the aforesaid devices, namely, beaters for mixing machines, gear drives for mixing machines, fluid pumps for mixing machines, mixing shafts for mixing machines, mixing plates for mixing machines, retaining rods for mixing machines, tubing for mixing machines