Patent ID: 7354493

Claim:
A method of patenting at least one steel wire, comprising the steps of: heating said at least one steel wire to an austenitisation temperature of steel, ejecting pressurized gas bubbles into a mass of cooling liquid, in a manner which is guided upwards, and entraining said cooling liquid by said bubbles in a form of at least one cooling liquid curtain with an upward turbulent flow, abruptly cooling said at least one wire, in said cooling liquid which has reached austenitisation temperature, by passing said at least one steel wire through said at least one cooling liquid curtain, the at least one cooling liquid curtain exhibiting said upward turbulent flow being oriented substantially transversely to said at least one moving wire, while obtaining a cooling temperature situated below the austenitisation temperature and above a martensitic transformation temperature, adjusting a successive number of the cooling liquid curtains, the number being determined so as to obtain, by the said cooling said wire in said cooling liquid, a perlitic transformation temperature to be maintained during a step of maintaining said at least one wire in an isothermal state, as the cooling temperature; and performing the step of maintaining said at least one steel wire in the isothermal state at the perlitic transformation temperature until completion of a perlitic transformation, wherein the step of maintaining said at least one steel wire in the isothermal state is performed directly following the step of cooling in the cooling liquid.