JPH02159322A - Horizontal type furnace - Google Patents

Abstract

PURPOSE:To provide a horizontal type furnace, of which problem on the operation, such as deterioration of quality, meandering, in a material to be heat-treated is solved, by arranging uniformizing means for tension distribution in the furnace. CONSTITUTION:Hearth rolls 5, each tension meter 3, 6 at front and rear of the furnace 4 and bridle rolls 2, 7 are arranged and at first, speed reference signal is outputted time sequentially to each speed control unit 9 for rolls 2, 5, 7 with a speed reference setter 12. On the other hand, feedback signal from a speed meter of a motor 8 is made to feedback to the unit 9, and the roll 7 controlled with these two signals is made to the speed reference roll. On the other hand, the signal from the meter 3 and a tension reference signal of a furnace inside tension setter 11 in accordance with material condition of a strip 1 are compared with a tension control unit 10. The tension at inlet side of the furnace 4 is controlled by using a speed correcting signal based on the deviation signal through the motor 8 for the rolls 2 and the above unit 9 for the rolls 2, and as the same way the tension in the furnace 4 is controlled by the signal from the meter 6 through the motor 8 for the rolls 5. By this method, the tension of the strip 1 in the furnace 4 can be made uniform over the whole length of the furnace 4.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a horizontal furnace.

[Prior Art] In-furnace tension control in a conventional horizontal furnace was performed as follows.

■Mortal current control is performed by bridle rolls related to tension control.

■Feed back control of the above-mentioned pre-roll by the signal from the tension meter installed on the furnace entry side or the furnace exit side.

[Problems to be Solved by the Invention] However, in conventional tension control, the actual tension in the furnace is unknown in the case (2) above, and the actual tension value is known at the entrance side or near the furnace exit side in the case (2) above. However, it was not possible to control the tension uniformly over the entire length of the furnace. For this reason, when it is necessary to control the tension uniformly over the entire length of the furnace for quality control of the object to be heat treated or for stable operation, sufficient control cannot be achieved, resulting in problems such as deterioration of product quality and meandering.

An object of the present invention is to solve the above-mentioned problems and provide a means for making the tension in the furnace uniform over the entire length of the furnace.

"Means for Solving the Problems" The horizontal furnace according to the present invention has tension meters and bridle rolls arranged before and after the furnace, a hearth roll for conveying the object to be heat-treated in the furnace, and a speed control 81 for the roll. A tension control device is provided with a function that compares the tension reference value from the furnace tension reference setting device with the actual tension value from the tension actual measurement value by the tension meter, and corrects the roll speed reference based on the deviation signal. This is a horizontal furnace.

[Operation] In the horizontal furnace of the present invention, tension feedback control is performed based on signals from tension meters disposed before and after the furnace, so that the tension in the furnace of the object to be heat treated is made uniform over the entire length of the furnace.

[Embodiment] FIG. 1 is a flowchart showing an embodiment according to the present invention. This will be explained below using this figure.

The strip 1 is introduced into a furnace 4 via an entrance-side bridle roll 2 and a furnace-entry tension meter 3. The strip 1 is transported in the furnace by an in-furnace hearth roll 5, and after the heat treatment is completed, it reaches the furnace outlet bridle roll 7 via an outlet tension meter 6. The above is a series of mechanical equipment related to in-furnace tension control. Next, the operation of the control device according to the present invention will be explained. First, the speed standard setting device 12 sets the speed K of the 1, furnace entry side bridle roll 2, furnace hearth roll 5, and furnace exit side bridle roll 7.
A time-series speed reference signal is issued to the m device 9. On the other hand, a feedback signal from the speed meter (not shown) of the motor 8 is fed back to the speed control device 9.The furnace outlet side bridle roll 7 is a speed reference roll controlled by these two signals. The tension setting device 11 sets the tension according to the material conditions of the strip 1, and issues a tension reference signal to the tension control device 10.

The tension control on the furnace entry side is as follows. That is, the signal from the furnace entry side tension meter 3 is transmitted to the tension control device 10.
If there is a difference from the tension reference signal, a speed correction signal based on the tension deviation signal is sent to the speed control device 9 of the bridle roll 2 on the furnace entry side. The speed control device 9 of the bridle roll 2 on the entrance side receives the speed reference signal and the speed correction signal, and ultimately controls the tension on the entrance side by changing the speed of the motor 8 of the bridle roll on the entrance side. .

The tension control inside the furnace is as follows. That is, the signal from the furnace outlet tensile meter 6 is sent to the tension control device 10, and if there is a difference from the tension reference signal, a speed correction signal based on the tension deviation signal is sent to the speed control device 9 of the in-furnace hearth roll 5. emanates from. A speed control device 9 for the furnace hearth roll 5 receives the speed reference signal and the speed correction signal,
Finally, the tension in the furnace is controlled by changing the speed of the motor 8 of the hearth roll 5 in the furnace.

Figure 2 is a graph showing the effects of the present invention. This figure shows the actual measured values of the tension on the inlet and outlet sides of the furnace in this example. When controlled by the equipment of the present invention, there is a difference of about 200 kg between the tension at the furnace entry side and the tension at the furnace exit, as shown in Figure (b), but when controlled by the equipment of the present invention, (a) As shown in the figure, both are almost equal.

[Effects of the Invention] As described above, according to the present invention, since the tension distribution inside the furnace is constant, the quality of the material to be heat-treated can be stably obtained, and operational problems such as meandering can be avoided. This has the effect of avoiding troubles.

[Brief explanation of the drawing]

FIG. 1 is a flowchart showing an embodiment of the present invention;
FIG. 2 is a graph showing the effects of the present invention. 1...Strip, 2...Furnace entry side bridle roll, 3...Furnace entry side tension meter, 4...Furnace, 5
Furnace hearth roll, 6 Furnace outlet tension meter 7 Furnace outlet bridle roll, 8 Motor 9 Speed controller, 10 Tension controller,
11...Furnace tension setting device, 12...Speed standard setting device.

Claims (1)

[Claims] A tension meter and a bridle roll are arranged before and after the furnace, and a hearth roll for conveying the material to be heat treated is arranged in the furnace, and a speed control function is attached to this roll, and the tension reference value from the furnace tension reference setting device and the above A horizontal furnace equipped with a tension control device that compares the actual tension value measured by a tension meter with the actual tension value and corrects the roll speed standard based on the deviation signal.