Řízení pevnosti drátu válcovaného z kordové oceli C70K

Abstract

The wire drawing plant requires a reduction of the strength of C70K cord steel wire, which would allow a removal of the intermediate operation of patenting in the cold drawing process. The goal of this thesis is to verify the possibilities of controlled cooling on a STELMOR continuous wire conveyor in TŘINECKÉ ŽELEZÁRNY, Ltd. and determine what effect different cooling rates have on the resulting mechanical properties. The dilatometric tests in combination with metallographic analyses and hardness measurements led to the creating of ARA diagram in limited range of cooling rates. Based on these result, three variants of controlled cooling of the wire on the STELMOR conveyor with as larges possible difference in the average cooling rate were designed and implemented. Among other things the operationally rolled wire was subjected to standard tensile tests, which resulted in the recommendation of suitable strategy for the controlled cooling of the steel wire.