A heating system for drill steel pipe billet includes a feedback device configured to control distances d.sub.1 and d.sub.2 of three flamethrowers, a propulsion device, a positioning device, a heating device, a temperature measuring device and a conveying device. Heating temperature of the flamethrowers is controlled by an oxygen distribution box and a gas distribution box. A heating method for the drill steel pipe billet is also provided, in which a rolling forming method of gradient flame heating is adopted to control density of the rolled pieces and avoid internal defects of the drill steel caused by the same deformation of the traditional uniformly heated pipe billets. A radial temperature of the drill steel pipe billet is accurately controlled through the feedback device. Only one set of flamethrowers corresponding to drill steel pipe billets of different dimensions is required, and other devices are universal components, which will not be replaced.

A heating system for drill steel pipe billet includes a feedback device configured to control distances d.sub.1 and d.sub.2 of three flamethrowers, a propulsion device, a positioning device, a heating device, a temperature measuring device and a conveying device. Heating temperature of the flamethrowers is controlled by an oxygen distribution box and a gas distribution box. A heating method for the drill steel pipe billet is also provided, in which a rolling forming method of gradient flame heating is adopted to control density of the rolled pieces and avoid internal defects of the drill steel caused by the same deformation of the traditional uniformly heated pipe billets. A radial temperature of the drill steel pipe billet is accurately controlled through the feedback device. Only one set of flamethrowers corresponding to drill steel pipe billets of different dimensions is required, and other devices are universal components, which will not be replaced.

A steel sheet temperature control device including: a sheet temperature measurement unit; a furnace temperature measurement unit; an influence coefficient calculation unit; a control model setting unit that sets a control model; a state variable/disturbance estimation unit that estimates values of a state variable and a temperature disturbance variable of the control model at the same time; a furnace temperature change amount calculation unit that calculates a furnace temperature change amount of each of heating zones of a heating furnace under a constraint condition such that square sum of a deviation between a target value and the actual value of the temperature of the steel sheet at the outlet side of the heating furnace becomes minimum; and a furnace temperature control unit that controls a fuel flow rate used in each of the heating zones to achieve the calculated furnace temperature change amount.

A steel sheet temperature control device including: a sheet temperature measurement unit; a furnace temperature measurement unit; an influence coefficient calculation unit; a control model setting unit that sets a control model; a state variable/disturbance estimation unit that estimates values of a state variable and a temperature disturbance variable of the control model at the same time; a furnace temperature change amount calculation unit that calculates a furnace temperature change amount of each of heating zones of a heating furnace under a constraint condition such that square sum of a deviation between a target value and the actual value of the temperature of the steel sheet at the outlet side of the heating furnace becomes minimum; and a furnace temperature control unit that controls a fuel flow rate used in each of the heating zones to achieve the calculated furnace temperature change amount.

Iron-based alloys and articles in strips, sheets, workpieces and the like are converted into high strength steel with a minimum of cost, time and effort, including producing dual phase materials. This is achievable by extremely rapid micro-treating of low, medium, and high carbon iron-based alloys and articles by rapid heating and rapid cooling at least a portion of the alloy/article. This heating step involves nearly immediately heating the iron-based alloy to a selected temperature above its austenite conversion temperature. Then, the alloy is immediately quenched, also at an extremely fast rate, on at least a portion of the iron-based alloy in a quenching unit adjacent the heating unit. This procedure forms high strength alloy in a desired area, depending upon where the treatment was performed.

Iron-based alloys and articles in strips, sheets, workpieces and the like are converted into high strength steel with a minimum of cost, time and effort, including producing dual phase materials. This is achievable by extremely rapid micro-treating of low, medium, and high carbon iron-based alloys and articles by rapid heating and rapid cooling at least a portion of the alloy/article. This heating step involves nearly immediately heating the iron-based alloy to a selected temperature above its austenite conversion temperature. Then, the alloy is immediately quenched, also at an extremely fast rate, on at least a portion of the iron-based alloy in a quenching unit adjacent the heating unit. This procedure forms high strength alloy in a desired area, depending upon where the treatment was performed.

The present invention discloses a heating system for drill steel pipe billet, comprising a feedback device, a propulsion device, a positioning device, a heating device, a temperature measuring device and a conveying device. The distance d.sub.1 and d.sub.2 of three flamethrowers are controlled through the feedback device. The heating temperature of the flamethrowers is controlled by the oxygen distribution box and the gas distribution box. On the other hand, the present invention also provides a heating method for drill steel pipe billet, which adopts the rolling forming method of gradient flame heating, which realizes the control of the density of the rolled pieces, avoiding the internal defects of the drill steel caused by the same deformation of the traditional pipe billet after uniform heating, improving the quality of the drill steel, and prolonging the service life of the drill steel. The radial temperature of the drill steel pipe billet is accurately controlled through the feedback device. Flame heating with low cost is adopted. For drill steel pipe billets of different dimensions, only a set of flamethrowers corresponding to the dimensions needs to be designed, and other devices are universal components, which do not need to be replaced.

A steel sheet temperature control device including: a sheet temperature measurement unit; a furnace temperature measurement unit; an influence coefficient calculation unit; a control model setting unit that sets a control model; a state variable/disturbance estimation unit that estimates values of a state variable and a temperature disturbance variable of the control model at the same time; a furnace temperature change amount calculation unit that calculates a furnace temperature change amount of each of heating zones of a heating furnace under a constraint condition such that square sum of a deviation between a target value and the actual value of the temperature of the steel sheet at the outlet side of the heating furnace becomes minimum; and a furnace temperature control unit that controls a fuel flow rate used in each of the heating zones to achieve the calculated furnace temperature change amount.

A steel sheet temperature control device including: a sheet temperature measurement unit; a furnace temperature measurement unit; an influence coefficient calculation unit; a control model setting unit that sets a control model; a state variable/disturbance estimation unit that estimates values of a state variable and a temperature disturbance variable of the control model at the same time; a furnace temperature change amount calculation unit that calculates a furnace temperature change amount of each of heating zones of a heating furnace under a constraint condition such that square sum of a deviation between a target value and the actual value of the temperature of the steel sheet at the outlet side of the heating furnace becomes minimum; and a furnace temperature control unit that controls a fuel flow rate used in each of the heating zones to achieve the calculated furnace temperature change amount.

Iron-based alloys and articles in strips, sheets, workpieces and the like are converted into high strength steel with a minimum of cost, time and effort, including producing dual phase materials. This is achievable by extremely rapid micro-treating of low, medium, and high carbon iron-based alloys and articles by rapid heating and rapid cooling at least a portion of the alloy/article. This heating step involves nearly immediately heating the iron-based alloy to a selected temperature above its austenite conversion temperature. Then, the alloy is immediately quenched, also at an extremely fast rate, on at least a portion of the iron-based alloy in a quenching unit adjacent the heating unit. This procedure forms high strength alloy in a desired area, depending upon where the treatment was performed.