JPH0610055A - Annealing temperature controller of continuous annealing equipment - Google Patents

Abstract

PURPOSE:To control the annealing temp. in an on-line and to execute annealing uniformly in the longitudinal direction without using expensive equipment. CONSTITUTION:As for a hoop 16 in the outlet side of continuous annealing equipment 1 to which elongation peacentage is imparted by an inlet side bridle 12 and an outlet side bridle 14 before and behind a skinpass mill or a tension leveler 10, tension is measured by a tension gauge 18, and from the change of this tension, the variation DELTAF in the tension is detected. Based on the DELTAF, the annealing temp. of the continuous annealing equipment 1 is controlled by an annealing temp. controller 32.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an annealing temperature control device for continuous annealing equipment.

[0002]

2. Description of the Related Art Conventionally, as a method of controlling the annealing temperature of continuous annealing equipment, a plate thermometer is installed on the outlet side of the annealing furnace to measure the plate temperature of a steel strip, and the plate temperature is set to a set value. The annealing temperature was controlled.

A method of controlling the annealing temperature by detecting the crystal grains and hardness of the steel strip online by using a grain size meter or a magnetic type hardness measuring device can be considered.

[0004]

As described above, the purpose of controlling the annealing temperature based on the plate temperature on the outlet side of the annealing furnace is to obtain a uniform material in the longitudinal direction of the steel strip. However, the state of the steel strip before annealing, for example, the material depends on the material difference such as composition, rolling temperature, rolling reduction, etc. There was a problem that it was not always obtained.

Further, in the case of online control using the above-mentioned grain size meter or magnetic hardness measuring instrument, the equipment cost is high, and it is necessary to have a lot of data as a reference of the material to be measured. It was difficult to put into practical use due to problems such as not being easy to maintain.

The present invention has been made in view of the above problems of the prior art, is relatively inexpensive in equipment cost, and does not require preparation of data as a reference of a material to be measured, and maintenance is not required. An object of the present invention is to provide an annealing temperature control device for continuous annealing equipment that is easy and can be controlled online so that the material of the steel strip is uniform in the longitudinal direction.

[0007]

SUMMARY OF THE INVENTION The present invention is directed to an elongation rate control device which is arranged on the outlet side of a continuous annealing equipment and which gives a constant elongation rate to a steel strip that is passing through. A tension measuring device that measures the tension of a given steel strip, and a control that detects the change in tension based on the measured value of this tension measuring device and controls the annealing temperature of the continuous annealing equipment according to the amount of change in the tension. The above-mentioned object is achieved by an annealing temperature control device of a continuous annealing equipment having an apparatus.

[0008]

The present invention focuses on the fact that when the steel strip to which the elongation has been applied changes in material, this appears as a change in the tension of the steel strip, and the elongation is controlled by the elongation control device. The change in tension of the steel strip that is annealed while being given an elongation rate is detected, and the annealing temperature is controlled based on the change in tension, so that the steel strip can be lengthened in the longitudinal direction online without expensive equipment. Can be annealed uniformly.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

In this embodiment, the entrance side bridle 12 and the exit side bridle 14 of the skin pass mill or tension leveler 10 arranged on the exit side of the continuous annealing equipment 1 are used as constituent elements of the elongation control device 20. , These entrance bridle 12 and exit bridle 14
Steel strip that passes through a skin pass mill or tension leveler 10
6 is given a predetermined elongation, that is, a speed difference.

The entrance side bridle 12 and the skin pamil or
A tensiometer 18 for measuring the tension of the steel strip 16 is arranged between the tension leveler 10 and the tension leveler 10. The tensiometer 18 is also configured as a part of the elongation control device 20.

The elongation control device 20, as shown in FIG. 1, includes a tension converter 22, a PLG 24, and a speed calculator 2.
6, an elongation rate calculator 28 and a tension change amount calculator 30 are included. Further, the signal from the elongation control device 20 is output to the annealing temperature control device 32.

The tension converter 22 converts the output signal of the tensiometer 18 into a steel strip tension F, and the speed calculator 26 changes the feed amount L of the steel strip 16 at the position of the outlet bridle 14. The line speed V _D is calculated and output based on the signal from the PLG 24 output accordingly.

The elongation rate calculator 28 calculates and outputs the substantial elongation rate ε'of the steel strip 16 from the speed difference between the entrance side bridle 12 and the exit side bridle 14.

The tension change amount calculator 30 receives the signal F of the steel strip tension from the tension converter 22 and the speed calculator 2.
Based on the line speed signal V _D from 6 and the set elongation rate set value ε, the actual elongation rate ε ′ from the elongation rate calculator 28, and the material correction value M input value, the tension change of the steel strip 16 The amount ΔF is calculated.

The annealing temperature control device 32 controls the annealing temperature in the continuous annealing equipment based on the signal of the tension change amount ΔF input from the tension change amount calculator 30.

For example, if the tension change amount ΔF is positive,
The hardness of the corresponding part of the steel strip 16 is too high,
On the contrary, if it is negative, it means that the corresponding portion of the steel strip 16 has insufficient hardness, and the annealing temperature control device 32 controls the annealing temperature in the continuous annealing equipment so as to compensate for the excess and deficiency of these hardnesses. ing.

Next, the operation of the apparatus of the above embodiment will be described.

Skin pass mill or tension leveler 10
The steel strip 16 passing through the
A predetermined elongation rate ε, that is, a speed difference (V_D
-V _E) Is given.

The tension of the steel strip 16 between the entrance-side bridle 12 and the exit-side bridle 14 is detected by a tensiometer 18, and this signal is converted into a tension signal F by a tension converter 22 to change the tension. It is input to the calculator 30. On the other hand, the speed calculator 26 calculates the line speed V _D of the steel strip 16 on the basis of the signal from the PLG 24 corresponding to the feed amount of the steel strip 16 in the exit side bridle 14, and this is calculated by the elongation rate calculator 28 and the tension. Output to the change amount calculator 30.

The elongation rate calculator 28 calculates an elongation rate ε'substantially given to the steel strip 16 based on the input signal of the line speed V _D and outputs it to the tension change amount calculator 30.

The tension change amount calculator 30 calculates the tension change amount ΔF from the input tension signal F, line speed V _D , correction value M, set elongation ε and actual elongation ε ', and anneals this signal. Output to the temperature control device 32.

Here, what detects the actual elongation rate ε'and inputs it to the tension change amount calculator 30 is that when the line speed V _D is changed, the change in the strain rate of the steel strip 16 affects the steel strip output F. Changes, so that the tension change amount ΔF can be accurately detected by correcting the speed and making it the same as in the constant speed state. Here, since the strain rate further changes depending on the material of the steel strip, the correction value M is added to calculate the tension change amount ΔF more accurately.

FIG. 2 shows an example of actual control. As shown in the figure, when the annealing temperature in the continuous annealing equipment is increased / decreased according to the increase / decrease in the tension change amount ΔF, the outlet plate temperature measured at the outlet of the annealing furnace is shown in the second stage from the bottom of FIG. As shown in the bottom of FIG. 2, the hardness or tensile strength of the steel strip 16 becomes substantially uniform in the longitudinal direction. In the conventional case, the hardness or the tensile strength was changed according to the increase / decrease in the annealing furnace outlet plate temperature.

In this embodiment, the material in the longitudinal direction of the steel strip after continuous annealing can be made uniform on-line without the need for expensive equipment.

By recording the input signal of the tension change amount calculator 34 and the tension change amount signal ΔF without performing the annealing temperature control, the abnormal portion can be determined and the abnormal portion is cut off. As a result, it is possible to eliminate the abnormal portion from being mixed in the product. Furthermore, by preparing data that serves as a reference for the material to be measured, it is possible to evaluate the hardness, tensile strength, etc. based on the steel strip tension.

In the above embodiment, the entrance side bridle 12 is attached to the skin pass mill or the ten leveler after the continuous annealing equipment.
And, the outlet side bridle 14 is provided, and the elongation rate is controlled by this, but the present invention is not limited to this, and a continuous path equipment such as a skin pass mill or a tension leveler is provided in-line as a shape correcting device. When installed, these can be replaced with an elongation control device and used to reduce the equipment cost.

[Brief description of drawings]

FIG. 1 is a partial block diagram showing an embodiment of an annealing temperature control device for continuous annealing equipment according to the present invention.

FIG. 2 is a diagram showing an example of annealing temperature control by the apparatus of the embodiment.

[Explanation of symbols]

 1 ... Continuous annealing equipment 10 ... Skin pass mill or tension leveler 12 ... Incoming bridle 14 ... Outgoing bridle 16 ... Steel strip 18 ... Tensometer 20 ... Extension control device 22 ... Tension transducer 24 ... PLG 26 ... Speed calculator 28 ... Elongation rate calculator 30 ... Tension change amount calculator 32 ... Annealing temperature control device

Claims (1)

[Claims] Claim: What is claimed is: 1. An elongation rate control device, which is arranged on the outlet side of a continuous annealing facility and gives a constant elongation rate to a passing steel strip, and a tension of the steel strip to which the elongation rate is given by the elongation rate control device. And a controller for detecting a change in tension based on a measurement value of the tension measuring device and controlling the annealing temperature of the continuous annealing equipment according to the amount of change in the tension. Annealing temperature controller for continuous annealing equipment.