Method for breaking steel rod into billets
AssigneesKabushiki Kaisha Toyota Chuo Kenkyusho, Aichi Steel Works, Ltd.
InventorsShigetsune Aoyama, Masahiko Kato, Motoo Matsubara, Osamu Furuta
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Abstract
A method for breaking a steel rod into billets for forging, rolling, etc., by cutting a circumferential notch in the surface of the steel rod, locally heating the surface areas of the rod adjacent the notch so that the temperature at the notch bottom is less than a transformation temperature of the steel of the rod, quenching the rod thereby to develop a crack extending from the notch bottom toward the center of the rod, and applying a mechanical load to break the rod along its notched portion.
Claims19
A method for breaking a steel rod into billets comprising the steps of:
- forming a circumferential notch in the surface of the steel rod, locally heating the surface areas of the steel rod adjacent such notch so that the surface of the rod at the bottom of the notch is at a temperature less than that at which transformation of ferrite to austenite occurs,
- quenching the rod to thereby develop a crack extending from the bottom of said notch toward the center of the rod, and
- applying a mechanical load to break the rod along said circumferential notch.
A method for breaking a steel rod into billets comprising the steps of:
- forming a circumferential notch in the surface of the steel rod, locally heating the surface of said steel rod a first time in the areas surrounding said notch to a temperature above a transformation point of the steel of the rod,
- quenching the rod to thereby harden the surface of the rod in the areas surrounding said circumferential notch,
- locally heating the surface of the rod a second time in the areas surrounding said circumferential notch to such a temperature that the surface temperature of the rod at the bottom of said notch is less than a transformation temperature of the steel of said rod,
- quenching the rod to thereby develop a crack extending from the bottom of said notch toward the center of the rod, and
- applying a mechanical load to break the rod along said circumferential notch.
Dependencies are inferred from the claim text.