Abstract: Method of and plant for patenting steel wire bundles, according to which a cooling vat is heated by a heating fluid to a temperature of e.g. 500.degree. C considered as cooling temperature for patented steel wire bundles. Into this cooling vat is then introduced the steel wire bundle to be patented which in this way is pre-heated. The thus pre-heated steel wire bundle is subsequently introduced into a hot fluid containing heating vat where the wire bundle is heated to a patenting temperature of e.g. 900.degree. C. After the wire bundle has been patented in this heating vat, it is returned to the cooling vat where it is cooled to the cooling temperature prevailing therein while the cooling vat due to the absorption of heat from the wire bundle being cooled substantially maintains its cooling temperature from one cooling step to the next cooling step.