Abstract: Cooling by a gas coolant of carbon steel wire coils which have been heated to above the austenizing temperature of the wire is controlled to rapidly quench cool the wire coils to within a selected critical range of temperatures which results in a desired fine pearlitic crystalline structure of the steel wire, by controlling the impingement pattern and velocity of the coolant gas on the wire. The coolant gas is discharged through individual coolant gas inlet conduits, thence through a plurality of individual enclosed plenum boxes, onto the heated coils as the coils are transported past the boxes by a conveyor device. Each plenum box has a series of gas-discharge slots formed in the bottom thereof, through which slots the gas is discharged onto the coils. The distance between the discharge slots of each box and the wire coils may be selectively adjusted by raising or lowering individual ones of the plenum boxes relative to the level of the wire coils on the conveyor device.

Abstract: Cooling by a gas coolant of carbon steel wire coils which have been heated to above the austenizing temperature of the wire is controlled to rapidly quench cool the wire coils to within a selected critical range of temperatures which results in a desired fine pearlitic crystalline structure of the steel wire, by controlling the impingement pattern and velocity of the coolant gas on the wire. The coolant gas is discharged through individual coolant gas inlet conduits, thence through a plurality of individual enclosed plenum boxes, onto the heated coils as the coils are transported past the boxes by a conveyor device. Each plenum box has a series of gas-discharge slots formed in the bottom thereof, through which slots the gas is discharged onto the coils. The distance between the discharge slots of each box and the wire coils may be selectively adjusted by raising or lowering individual ones of the plenum boxes relative to the level of the wire coils on the conveyor device.