TECHNICAL PAPERS
TECHNICAL PAPER Estimation of standard PN-EN 10264 – steel wire for rope A review of the EN10264 standard for steel wire for use in ropes has found that, while it is useful, it is lacking in some areas. The use of new indicators is suggested to produce more accurate results. By Ryszard Budzik, Bogdan Golis, Rafal Wludzik, Jan W. Pilarczyk and Wieslaw Waszkielewicz
Countries that belong to the European Union manufacture steel wire for ropes to requirements specified in standard EN 10264. In Poland, this standard is marked as PN-EN10264. This paper reviews the effectiveness of the relationships among strength properties (Rm= tensile strength) and technological ones (Nb = number of bends and Nt = number of bends) of steel wire for ropes described in this standard. The research has led the authors to believe that the standard, as written, is lacking. Instead of using three properties (Rm, Nb and Nt) to estimate wire quality, new indicators based on above mentioned properties have been suggested: Wb = Rm/N b; W t = Rm/N t ; and W = W b + W t . These new indicators make it possible to estimate the quality of steel rope wire as this methodology better presents the relationship
between wire strength and technological properties. Using these indicators, some errors in analyzed standards were found. The authors believe that their new indicators can not only provide a good estimation for wire quality, but also for the quality of strands and rope made from those wires. It is also possible to calculate the fatigue strength of ropes on the basis of indicator values for wires.
Introduction Wires and wire products make up a considerable part of the group of plastic-worked steel products that often operate under high external loads. These products include ropes and different types of cables, springs, tire reinforcement steel cords, strings and steel wires for the reinforcement of concrete (post-tensioned pre-stressed concrete). The behavior of these products in various structures and machine parts, and their reliable, smooth and safe operation, all depend to a considerable extent on their mechanical and engineering properties. Experience has shown that the most useful test for the evaluation of wire quality is the tensile test, which determines factors that include mechanical properties, while the nominal tensile strength (Rm) characterizes wire quality.
Fig. 1. The change of indicator Wb in relation to the nominal tensile strength of the class B rope wires from 0.75 mm to 1.7 mm.
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