Process capability indexes can be defined as statistical measures of process capability: the ability of a process to produce output within specification limits. It is important especially in case of ribbed bars where all characteristics should be kept. Ribbed bars are used in reinforced concrete structures and provide a better grip of the reinforcement to the concrete due to their shapes and the same time bigger contact surface. Recipients of ribbed bars demand that they have high strength and toughness, corrosion resistance, good weldability and high fatigue resistance. The process capacity indexes can be used for evaluation of repeatability of different characteristics. Cp index determines the ability of the process to manufacture products with constant properties, while Cpk index includes both natural variability of characteristic and the position of the average value in relation to the tolerance limits. In the paper Cp and Cpk indexes were calculated for the mass of 1 m of the ribbed bars with a diameter of 10,16 and 25 mm made of steel BSt500S.Keywords: ribbed bars, capacity, Cp/Cpk
© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.