Abstract: The coating on the stator vanes in a flotation machine is subject to abrasive load caused by the air/suspension flow and acting on the top part of the vane facing the rotor. In prior art, the coating placed on the vane was stationarily joined, serving single use only. In the invention a detachable coating (6) has been developed, which is placed like a sock upon the stator vane (4) and secured in place with the aid of a cover member (8). This securing, or locking, is accomplished with the aid of a groove (7) machined in the stator vane and of tooth-like projections (9) provided on the cover member. A locally worn-out coating may be detached and either turned through 180.degree. or inverted and put back in its place.