JP2001172725A - In-furnace atmosphere control device in rolling metal strip - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an in-furnace atmosphere control device to control the pressure of the predetermined in-furnace atmospheric gas while taking into consideration the leakage at a holding point of seal members in the case of charging the atmospheric gas into a heating furnace of a rolled metal strip. SOLUTION: A pair of seal members 2 to hold the metal strip S passing through the heating furnace from both sides thereof is installed facing to a strip inlet 1A and a strip outlet 1B of the heating furnace, an atmospheric gas charging unit 4 and an atmospheric gas discharging unit 3 are communicated with the outlet side and the inlet side of the furnace partitioned by the seal members, respectively, the pressure of the in-furnace atmospheric gas is measured, and the opening of a pressure regulating valve 5 provided on the atmospheric gas discharging unit 3 is regulated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to a continuous bright annealing furnace for strip-shaped strips such as strip-shaped stainless steel sheets.
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a furnace atmosphere control device that controls the pressure of the atmosphere in a heating furnace when performing required processing in a continuous heating furnace such as a non-oxidizing annealing furnace.

[0002]

2. Description of the Related Art Such a heating furnace sealing device includes:
Already disclosed in JP-A-9-194951 and JP-A-9-2004
No. 6, JP-A-10-46261 and the like are known. Here, a sealing roll is rolled on both sides of the strip-shaped metal strip introduced into the BA heating furnace and led out therefrom at the inlet and outlet of the heating furnace, and the outside of the atmosphere in the heating furnace is leaked. Has been prevented.

[0003]

However, in the BA heating furnace presented here, pressure control is performed because the internal atmosphere gas must be maintained at a required pressure. The amount of gas leak from the sandwiched portion changes depending on the contact pressure when the above-mentioned sealing roll (or pad sealing member) is sandwiched with the conveyed strip strip. In order to compensate for this, it is necessary to control the supply gas amount.

The present invention has been made on the basis of the above circumstances, and has as its object the purpose of considering the amount of leakage at a place where a seal member is sandwiched when introducing atmospheric gas into a furnace. An object of the present invention is to provide a furnace atmosphere control device capable of controlling a furnace atmosphere gas pressure.

[0005]

Therefore, in the present invention,
When performing required processing in the heating furnace on the rolled strip-shaped metal strip, in a furnace atmosphere control device for controlling the atmosphere in the heating furnace, the apparatus is opposed to the strip inlet and outlet of the heating furnace. Each of the strip-shaped metal strips passing through the heating furnace is equipped with a pair of seal members sandwiching from both surfaces thereof, and an atmosphere gas inlet is provided on the outlet side in the furnace partitioned by the seal members. Also,
An atmosphere gas discharge section is connected to the inlet port side, and the atmosphere pressure in the furnace is measured to adjust the opening of a regulating valve provided in the atmosphere gas discharge section.

[0006] In this case, as an embodiment of the present invention,
The control to calculate the amount of gas supplied from the atmosphere gas input unit and the degree of opening of the regulating valve so as to be set from the relationship value between the furnace pressure and the gas flow rate using the contact pressure of the seal member as a factor. It is effective to form a part, and further, in order to grasp the contact pressure in relation to the amount of leakage of the atmospheric gas at the place where the sealing member is sandwiched with respect to the strip-shaped strip, The furnace pressure and the atmosphere gas input amount (flow rate) in the fully closed state are plotted on a table obtained as a parameter, and the adjustment valve is opened to maintain an appropriate furnace atmosphere gas pressure. It is preferable that the control unit be operated so as to adjust the degree.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an embodiment of the present invention will be described with reference to the drawings regarding a heating furnace employed in a step of heat-treating (for example, 1120 ° C. to 1150 ° C.) a rolled strip-shaped stainless steel strip. This will be specifically described.

[0008] The furnace atmosphere control device here is connected to the strip inlet 1A and outlet 1B of the BA heating furnace 1 (which has a cooling zone in the latter half of the in-furnace transfer path of a strip-shaped stainless steel strip). Correspondingly, in a configuration in which the sealing rolls 2 and 2 as the sealing members are respectively provided, the sealing roll passes the strip-shaped strip S that is passed and conveyed through the furnace on both surfaces thereof.
An atmosphere gas discharge section 3 and an atmosphere gas input section 4 are provided inside the furnace at a location where the atmosphere gas discharge section 3 is in contact with each other via communication paths 3a and 4a. The strip-shaped metal strip is, for example, a rolled steel plate strip, and the atmospheric gas is, for example, a pressure of 20 to 5 in a furnace.
A mixed gas of _N 2, _{H 2} of 0 mmAq.

Further, a pressure regulating valve 5 is provided in the communication passage 3a of the atmosphere gas releasing section 3, and a control motor 6 for adjusting the opening is driven by a control signal from a control section 7. . On the other hand, a pressure sensor 8 is provided in a heating area of the BA heating furnace, and the measured value is compared with table information T prepared in advance in the control unit 7 and is taken out as the control signal.

That is, the amount of gas supplied from the atmosphere gas input section 4 and the opening degree of the pressure regulating valve 5 are determined by the sealing rolls 2 and 2.
Is calculated by the control unit 7 so as to be set from the relation value between the furnace pressure and the gas flow rate using the contact pressure as a factor, and the table information T is used as an effective means.

That is, the table information T is used to determine the pressure adjustment in order to grasp some of the contact pressures in relation to the leakage amount of the atmospheric gas at the place where the rolls 2 and 2 are sandwiched with the strip. It is obtained by plotting on a graph the furnace pressure and the atmosphere gas input amount (flow rate) in the fully closed state of the valve as parameters (see FIG. 2). Thereby, the opening degree of the adjusting valve for maintaining the pressure of the appropriate atmosphere gas in the furnace can be adjusted depending on the state of the contact pressure at the place where the rolls 2 and 2 are sandwiched.

The data shown in FIG. 2 is created under the following conditions and is a specific example of table information used in the present invention. Here, the contact pressure of the sealing member (2 kg / cm ² , 4 kg / c) when the mixing ratio (% by weight) of hydrogen in the atmosphere gas is 50%, 80%, and 100%.
m ² ). In this case, the contact pressure of the sealing member (sealing roll) is measured using a pressure sensor (not shown) and is provided to the control unit 7.

[0013]

As described in detail above, the present invention provides an in-furnace for controlling the atmosphere in a heating furnace when performing required processing in a heating furnace on a rolled strip-shaped metal strip. In the atmosphere control device, a pair of seal members for sandwiching the strip-shaped metal strip passing through the inside of the heating furnace from both sides thereof are provided, respectively, opposite to the strip inlet and the outlet of the heating furnace. In the partitioned furnace, the atmosphere gas inlet is connected to the outlet side, and the atmosphere gas outlet is connected to the inlet side. The atmosphere pressure in the furnace is measured, and the adjustment provided in the atmosphere gas outlet is performed. The opening degree of the valve is configured to be adjusted.

Therefore, when the atmosphere gas is introduced into the furnace, an effect is obtained that the predetermined atmosphere gas pressure in the furnace can be controlled in consideration of the amount of leakage at the location where the seal member is sandwiched.

[Brief description of the drawings]

FIG. 1 is a side view showing an entire configuration of a heating furnace according to an embodiment of the present invention.

FIG. 2 is a graph showing table information according to the embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 BA heating furnace 1A Strip inlet 1B Strip outlet 2 Sealing roll (seal member) 3 Atmospheric gas discharge section 3a Communication path 4 Atmospheric gas input section 4a Communication path 5 Pressure regulating valve 6 Control motor 7 Control section 8 Pressure sensor S Strip strip

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Shunichi Maru 1-3-28 Chuocho, Shibata-shi, Niigata F-term (reference) 4K043 AA01 BB05 DA05 EA07 FA08 FA11 GA02 GA03 GA10 4K056 AA09 BA02 CA02 DC11 FA10 FA27

Claims (3)

[Claims] 1. A furnace atmosphere control device for controlling an atmosphere in a heating furnace when a required processing is performed on the rolled strip strip in the heating furnace. Facing the outlet,
Equipped with a pair of seal members for sandwiching the strip strip passing through the heating furnace from both sides thereof, an atmosphere gas inlet portion on the outlet side of the furnace partitioned by the seal members, and an atmosphere gas inlet portion on the inlet side. A furnace atmosphere control in a strip-shaped metal rolling process, characterized in that the discharge section is connected to the furnace and the atmosphere pressure in the furnace is measured to adjust the opening of a regulating valve provided in the atmosphere gas discharge section. apparatus. 2. The gas supply amount from the atmosphere gas supply section and the opening degree of the regulating valve are set based on a relationship value between a furnace pressure and a gas flow rate with a contact pressure of the seal member as a factor. The furnace atmosphere control device in strip-shaped metal rolling according to claim 1, wherein the control unit is configured to perform a calculation. 3. The pressure in the furnace when the regulating valve is fully closed in order to grasp the contact pressure in relation to a leak amount of an atmospheric gas at a place where the sealing member is in contact with the strip-shaped strip. And the input amount (flow rate) of the atmosphere gas are plotted on a table obtained as a parameter, and the control unit is operated so as to adjust the opening degree of the adjustment valve for maintaining the pressure of the atmosphere gas in the furnace. The furnace atmosphere control device according to claim 2, wherein