Heat treatment apparatus, heat treatment method, medium on which heat treatment program is recorded, and steel product

A heat treatment apparatus comprising:

• a plurality of induction heating devices which are disposed on a rolling line of a steel product, and which are arranged at the rear stage of an accelerated cooling device swiftly cooling the rolled steel product;
• a correctional device which corrects the steel product;
• at least one temperature detector which is disposed on the rolling line and which detects a temperature of the steel product;
• a computing device which computes supply predetermined electric power which is supplied to the induction heating devices, on the basis of a size of the steel product, a conveying speed of the steel product, a heating target temperature of the steel product, and an actually measured temperature of the steel product measured by the temperature detector at the previous stage of the induction heating devices;
• and
• a power supply unit which supplies the supply predetermined electric power computed by the computing device to the induction heating devices,
• wherein the computing device computes supply predetermined electric power to be supplied to the induction heating devices in order to heat the steel product so that the steel product has a surface temperature equal to or lower than a first target temperature while being heated, and a difference between a second target temperature and a temperature which the steel product has at a predetermined position in the thickness direction of the steel product when the heating is completed falls within a predetermined range, or so that the steel product has a surface equal to or higher than a third target temperature while being heated and has a temperature equal to or lower than a fourth target temperature at the predetermined potion in the thickness direction of the steel product when the heating is completed.

A heat treatment apparatus comprising:

• a plurality of induction heating devices which are disposed on a rolling line of a steel product, and which are arranged at the rear stage of an accelerated cooling device swiftly cooling the rolled steel product;
• a correctional device which corrects correcting the steel product;
• at least one temperature detector which is disposed on the rolling line and which detects a temperature of the steel product;
• a first computing device which computes first supply predetermined electric power which is supplied to the induction heating devices, on the basis of a size of the steel product, a conveying speed of the steel product, a heating target temperature of the steel product, and a predetermined temperature of the steel product at the previous stage of the induction heating devices;
• a second computing device which computes second supply predetermined electric power which is supplied to the induction heating devices, on the basis of the size of the steel product, a conveying speed of the steel product, a heating target temperature of the steel product, and an actually measured temperature of the steel product measured by the temperature detector at the previous stage of the induction heating devices;
• an electric power selecting device which selects the first supply predetermined electric power as supply predetermined electric power when a difference between the predetermined temperature of the steel product and the actual measured temperature of the steel product is within a predetermined range, and which selects the second supply predetermined electric power as supply predetermined electric power when a difference between the predetermined temperature of the steel product and the actual measured temperature of the steel product is not within a predetermined range;
• and
• a power supply unit which supplies the supply predetermined electric power selected by the electric power selecting device to the induction heating devices,
• wherein the first and the second computing devices compute supply predetermined electric power to be supplied to the induction heating devices in order to heat the steel product so that the steel product has a surface temperature equal to or lower than a first target temperature while being heated, and a difference between a second target temperature and a temperature which the steel product has at a predetermined position in the thickness direction of the steel product when the heating is completed falls within a predetermined range, or so that the steel product has a surface equal to or higher than a third target temperature while being heated and has a temperature equal to or lower than a fourth target temperature at the predetermined potion in the thickness direction of the steel product when the heating is completed.

A heat treatment method of a heat treatment apparatus which includes a plurality of induction heating devices which heat a steel product, a correctional device for correcting the steel product, a computing device which computes supply predetermined electric power which is supplied to the induction heating device, and a power supply unit which supplies the supply predetermined electric power computed by the computing devices to the induction heating device, comprising:

• on the basis of a size of the steel product, a conveying speed of the steel product, heating target temperatures of the steel product, a predetermined temperature of the steel product at the previous stage of the induction heating device,
• a step of computing supply predetermined electric power to be supplied to the induction heating devices in order to heat the steel product so that the steel product has a surface temperature equal to or lower than a first target temperature while being heated, and a difference between a second target temperature and a temperature which the steel product has at a predetermined position in the thickness direction of the steel product when the heating is completed falls within a predetermined range;
• or
• a step of computing supply predetermined electric power to be supplied to the induction heating devices in order to heat the steel product so that the steel product has a surface equal to or higher than a third target temperature while being heated and has a temperature equal to or lower than a fourth target temperature at the predetermined potion in the thickness direction of the steel product when the heating is completed.

A heat treatment method of a heat treatment apparatus which includes a plurality of induction heating devices which are disposed on a rolling line of a steel product, and which are arranged at the rear stage of an accelerated cooling device swiftly cooling the rolled steel product, a correctional device which corrects the steel product, at least one temperature detector which is disposed on the rolling line and which detects a temperature of the steel product, a computing device which computes supply predetermined electric power which is supplied to the induction heating device, and a power supply unit which supplies the supply predetermined electric power computed by the computing device to the induction heating devices, comprising:

• on the basis of a size of the steel product, a conveying speed of the steel product, a heating target temperature of the steel product, and an actually measured temperature of the steel product measured by the temperature detector at the previous stage of the induction heating devices,
• a step of computing supply predetermined electric power to be supplied to the induction heating devices in order to heat the steel product so that the steel product has a surface temperature equal to or lower than a first target temperature while being heated, and a difference between a second target temperature and a temperature which the steel product has at a predetermined position in the thickness direction of the steel product when the heating is completed falls within a predetermined range;
• or
• a step of computing supply predetermined electric power to be supplied to the induction heating devices in order to heat the steel product so that the steel product has a surface equal to or higher than a third target temperature while being heated and has a temperature equal to or lower than a fourth target temperature at the predetermined potion in the thickness direction of the steel product when the heating is completed.

A heat treatment method of a heat treatment apparatus which includes a plurality of induction heating devices which are disposed on a rolling line of a steel product, and which are arranged at the rear stage of an accelerated cooling device swiftly cooling the rolled steel product, a correctional device which corrects the steel product, at least one temperature detector which is disposed on the rolling line and which detects a temperature of the steel product, a computing device which computes supply predetermined electric power which is supplied to the induction heating devices, and a power supply unit which supplies the computed supply predetermined electric power to the induction heating devices, comprising:

• a supply predetermined electric power computing step of computing supply predetermined electric power to be supplied to the induction heating devices in order to heat the steel product so that the steel product has a surface temperature equal to or lower than a first target temperature while being heated, and a difference between a second target temperature and a temperature which the steel product has at a predetermined position in the thickness direction of the steel product when the heating is completed falls within a predetermined range;
• or
• a supply predetermined electric power computing step of computing supply predetermined electric power to be supplied to the induction heating devices in order to heat the steel product so that the steel product has a surface equal to or higher than a third target temperature while being heated and has a temperature equal to or lower than a fourth target temperature at the predetermined potion in the thickness direction of the steel product when the heating is completed;
• a step of executing the supply predetermined electric power computing step on the basis of a size of the steel product, a conveying speed of the steel product, a heating target temperature of the steel product, a predetermined temperature of the steel product at the previous stage of the induction heating devices when a difference between the predetermined temperature of the steel product and the actual measured temperature of the steel product is within a predetermined range;
• and
• a step of executing the supply predetermined electric power computing step on the basis of the size of the steel product, a conveying speed of the steel product, a heating target temperature of the steel product, and an actually measured temperature of the steel product measured by the temperature detector at the previous stage of the induction heating devices when a difference between the predetermined temperature of the steel product and the actual measured temperature of the steel product is not within a predetermined range.

A recording medium on which a heat treatment program is recorded, of a heat treatment apparatus which includes a plurality of induction heating devices which heat a steel product, a correctional device which corrects the steel product, a computing device which computes supply predetermined electric power which is supplied to the induction heating device, and a power supply unit which supplies the supply predetermined electric power computed by the computing device to the induction heating devices,

• the recording medium recording a program thereon for making a computer execute,
• on the basis of a size of the steel product, a conveying speed of the steel product, a heating target temperature of the steel product, a predetermined temperature of the steel product at the previous stage of the induction heating devices,
• a step of computing supply predetermined electric power to be supplied to the induction heating devices in order to heat the steel product so that the steel product has a surface temperature equal to or lower than a first target temperature while being heated, and a difference between a second target temperature and a temperature which the steel product has at a predetermined position in the thickness direction of the steel product when the heating is completed falls within a predetermined range;
• or
• a step of computing supply predetermined electric power to be supplied to the induction heating devices in order to heat the steel product so that the steel product has a surface equal to or higher than a third target temperature while being heated and has a temperature equal to or lower than a fourth target temperature at the predetermined potion in the thickness direction of the steel product when the heating is completed.

A recording medium on which a heat treatment program is recorded, of a heat treatment apparatus which includes a plurality of induction heating devices which are disposed on a rolling line of a steel product, and which are arranged at the rear stage of an accelerated cooling device swiftly cooling the rolled steel product, a correctional device which corrects the steel product, at least one temperature detector which is disposed on the rolling line and which detects a temperature of the steel product, a computing device which computes supply predetermined electric power which is supplied to the induction heating device, and a power supply unit which supplies the supply predetermined electric power computed by the computing device to the induction heating devices,

• the recording medium recording a program thereon for making a computer execute,
• on the basis of a size of the steel product, a conveying speed of the steel product, a heating target temperature of the steel product, and an actually measured temperature of the steel product measured by the temperature detector at the previous stage of the induction heating devices,
• a step of computing supply predetermined electric power to be supplied to the induction heating devices in order to heat the steel product so that the steel product has a surface temperature equal to or lower than a first target temperature while being heated, and a difference between a second target temperature and a temperature which the steel product has at a predetermined position in the thickness direction of the steel product when the heating is completed falls within a predetermined range;
• or
• a step of computing supply predetermined electric power to be supplied to the induction heating devices in order to heat the steel product so that the steel product has a surface equal to or higher than a third target temperature while being heated and has a temperature equal to or lower than a fourth target temperature at the predetermined potion in the thickness direction of the steel product when the heating is completed.

A recording medium on which a heat treatment program is recorded, of a heat treatment apparatus which includes a plurality of induction heating devices which are disposed on a rolling line of a steel product, and which are arranged at the rear stage of an accelerated cooling device swiftly cooling the rolled steel product, a correctional device which corrects the steel product, at least one temperature detector which is disposed on the rolling line and which detects a temperature of the steel product, a computing device which computes supply predetermined electric power which is supplied to the induction heating devices, and a power supply unit which supplies the computed supply predetermined electric power to the induction heating devices,

• the recording medium recording a program thereon for making a computer execute:
• a supply predetermined electric power computing step of computing supply predetermined electric power to be supplied to the induction heating devices in order to heat the steel product so that the steel product has a surface temperature equal to or lower than a first target temperature while being heated, and a difference between a second target temperature and a temperature which the steel product has at a predetermined position in the thickness direction of the steel product when the heating is completed falls within a predetermined range;
• or
• a supply predetermined electric power computing step of computing supply predetermined electric power to be supplied to the induction heating devices in order to heat the steel product so that the steel product has a surface equal to or higher than a third target temperature while being heated and has a temperature equal to or lower than a fourth target temperature at the predetermined potion in the thickness direction of the steel product when the heating is completed;
• a step of executing the supply predetermined electric power computing step on the basis of a size of the steel product, a conveying speed of the steel product, a heating target temperature of the steel product, a predetermined temperature of the steel product at the previous stage of the induction heating devices when a difference between the predetermined temperature of the steel product and the actual measured temperature of the steel product is within a predetermined range;
• and
• a step of executing the supply predetermined electric power computing step on the basis of the size of the steel product, a conveying speed of the steel product, a heating target temperature of the steel product, and an actually measured temperature of the steel product measured by the temperature detector at the previous stage of the induction heating devices when a difference between the predetermined temperature of the steel product and the actual measured temperature of the steel product is not within a predetermined range.