JP2006283092A - Heat transfer enhancement apparatus, and walking beam type continuous heating furnace having the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a walking beam type continuous heating furnace capable of locally heating a specified position of a workpiece to be heated while suppressing an increase in the fuel consumption and a steep rise in the equipment cost, and maintaining the production efficiency. <P>SOLUTION: The walking beam type continuous heating furnace is provided in which a combustion burner 8 is arranged below skid beams 10, 12 to support and transport a work S to be heated, and a heat transfer enhancement apparatus 14 is arranged on a hearth side below the combustion burner 8. The heat transfer enhancement apparatus absorbs the infrared light radiated from the combustion burner 8, and locally generates the radiant heat toward a vicinity of a supporting part of the skid beams 10, 12 to support the workpiece S. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a heat transfer acceleration device for locally heating a specific part of a material to be heated in a heating furnace and a walking beam type continuous heating furnace provided with this device.

In recent years, walking beam type continuous heating furnaces have been widely adopted as continuous heating furnaces for heating continuously cast metal materials such as slabs, blooms, billets and the like into final products.
The metal material carried into the walking beam type continuous heating furnace (hereinafter referred to as the material to be heated) includes a skid button disposed at predetermined intervals on a plurality of fixed skid beams extending in parallel in the furnace length direction. The movable skid beam is disposed between a plurality of fixed skid beams and intermittently moves in the furnace length direction, and is transferred to the extraction side while alternately changing to a skid button of the movable skid beam.

  During the transport process of this walking beam type continuous heating furnace, the material to be heated is heated at a predetermined temperature by a flame injected from a combustion burner provided in the lower part of the furnace. The skid beam is cooled below the furnace temperature by the cooling water circulating inside, and the radiant heat of the flame of the combustion burner is blocked by the fixed and movable skid beams. Heat transfer characteristics in the vicinity of the contact portion of the material to be heated that are in contact with each other are lowered.

For this reason, the temperature in the vicinity of the contact portion of the heated material is lower than the temperature of the other portion of the heated material, and as a result, a skid mark is likely to occur in the heated material after extraction. Since this skid mark adversely affects the dimensional accuracy, quality, etc. of the product after rolling, it is desirable not to generate this.
As a method for suppressing the skid mark of the material to be heated, there is a method of extending the in-furnace time of the material to be heated by increasing the furnace length or slowing the conveying speed. However, this method increases the fuel consumption, increases the manufacturing cost, and decreases the productivity.

Therefore, an auxiliary combustion burner is arranged in the furnace separately from the combustion burner, and the flame of the auxiliary combustion burner is directly applied to the portion where the skid mark of the heated material is likely to be generated, or the high-temperature combustion gas is locally passed through the tube. The method of spraying and heating is considered (for example, refer patent document 1 and patent document 2).
Japanese Utility Model Publication No. 60-38658 Japanese Utility Model Publication No.57-27787

However, as in Patent Documents 1 and 2, the method of locally heating the portion where the skid mark of the material to be heated is likely to occur is a large number of combustion burners, auxiliary combustion burners, and piping connected to each burner. Therefore, the equipment cost will increase.
The present invention has been made in order to eliminate such inconveniences, and suppresses an increase in fuel consumption and equipment cost, and locally heats a specific position of a material to be heated while maintaining production efficiency. It is an object of the present invention to provide a heat transfer promotion device for a heating furnace and a walking beam type continuous heating furnace equipped with the device.

In order to solve the above problems, a heat transfer promotion device for a heating furnace according to the present invention is a heat transfer promotion device for locally heating a specific part of a material to be heated in a heating furnace, and dissipates from the flame of a combustion burner. It is a heat transfer facilitating device for a heating furnace that is arranged at a predetermined position in the heating furnace so that radiant heat is generated by absorbing infrared rays to be emitted and the radiant heat is directed to the specific part.
In the invention according to claim 2, the heat transfer promotion device for a heating furnace according to claim 1 is formed of a refractory material that generates radiant heat by absorbing infrared rays.
Moreover, invention of Claim 3 made the heat transfer acceleration | stimulation apparatus of the heating furnace of Claim 1 the member which has thermal radiation property.

The invention according to claim 4 comprises the heat transfer promoting device for a heating furnace according to claim 3 with a refractory and a heat radiation layer provided on a surface of the refractory facing the specific portion. did.
On the other hand, in the invention according to claim 5, a combustion burner is disposed below a skid beam that supports and conveys the material to be heated, and a furnace floor side below the combustion burner is provided with any one of claims 1 to 4. In the walking beam type continuous heating furnace in which the heat transfer promotion device described above is arranged, the specific portion of the material to be heated is set in the vicinity of a support portion that supports the material to be heated of the skid beam, and the heat transfer promotion device The vicinity of the support portion was locally heated.
Further, the invention according to claim 6 is the walking beam type continuous heating furnace provided with the heat transfer promotion device according to claim 4, wherein the heat transfer promotion device has a ridge line extending in a furnace length direction, and the ridge line extends from the ridge line. The two flat plates are arranged in a mountain shape so as to extend obliquely downward at a predetermined inclination angle, and the two flat plates face each other in the vicinity of the support portion.

According to the heat transfer acceleration device for a heating furnace according to the present invention, since the in-furnace time of the material to be heated is not extended, the fuel consumption and the manufacturing cost can be suppressed, and the production efficiency can be maintained.
In addition, according to the walking beam type continuous heating furnace according to the present invention, the above-described effects can be achieved, and the heat transfer promotion device locally heats the vicinity of the support portion that supports the heated material of the skid beam. Therefore, it is possible to prevent the occurrence of skid marks on the heated material after extraction.

Hereinafter, an embodiment of a walking beam type continuous heating furnace according to the present invention will be described with reference to the drawings.
FIG. 1 is a sectional view in the furnace width direction of the walking beam type continuous heating furnace, FIG. 2 is a sectional view in the furnace length direction of the walking beam type continuous heating furnace, and FIG. 3 is a walking beam type continuous heating furnace. It is a figure which shows the positional relationship of the principal part.
In the walking beam type continuous heating furnace of this embodiment, a furnace wall 2 and a hearth 4 formed by lining a refractory in a metal casing constitute a part of the furnace body 6.
A plurality of combustion burners 8 are arranged on the furnace wall 2 in parallel with each other at a predetermined interval in the furnace length direction.

  Above the plurality of combustion burners 8, a plurality of fixed skid beams 10 extending in parallel in the furnace length direction and a plurality of movables moving intermittently in the furnace length direction between the plurality of fixed skid beams 10. A skid beam 12 is disposed, and skid buttons 10 a and 12 a are provided at predetermined intervals above the fixed skid beam 10 and the movable skid beam 12. The fixed skid beam 10 and the movable skid beam 12 are set to a temperature lower than the furnace temperature by cooling water circulating inside.

Then, when the plurality of movable skid beams 12 move intermittently in the furnace length direction, the slab (material to be heated) S carried into the furnace body 6 has a skid button 10 a of the fixed skid beam 10 and the movable skid beam 12. It is conveyed toward the extraction side of the furnace body 6 while changing to the skid button 12a.
A plurality of heat transfer promotion devices 14 are arranged on the hearth 4 below the combustion burner 8.

These heat transfer promotion devices 14 are positioned below the fixed skid beam 10 and the movable skid beam 12, and are arranged in parallel at predetermined intervals in the furnace width direction while extending in the furnace length direction.
Each heat transfer promotion device 14 is a long member having a V-shaped cross section formed of a refractory material. A ridge line r extends in the furnace length direction, and two planar heat transfer plates are formed from the ridge line r. 14 a and 14 b are arranged in a mountain shape extending obliquely downward at a predetermined inclination angle, and are supported by a support member 16 rising from the hearth 4.

As shown in FIG. 3, the widthwise interval H1 between the fixed skid beam 10 and the movable skid beam 12 is about 1000 mm, and the vertical distance H2 between the heat transfer promoting device 14 and the fixed skid beam 10 (or the movable skid beam 12) is as follows. In the case of 1000 to 2000 mm, the opening angle α of the heat transfer plates 14 a and 14 b of the heat transfer promoting device 14 is set to about 60 degrees.
The slab S carried into the walking beam type continuous heating furnace configured as described above is directed toward the extraction side of the furnace body 6 while changing over to the skid button 10a of the fixed skid beam 10 and the skid button 12a of the movable skid beam 12. It will be transported.

  In this conveying process, the slab S is heated at a predetermined temperature by the flame injected from the combustion burner 8 provided in the lower part of the furnace, and the radiant heat of the flame of the combustion burner 8 There is a possibility that the heat transfer characteristic in the vicinity of the contact portion of the slab S which is blocked by the movable skid beam 12 and is behind the fixed skid beam 10 and the movable skid beam 12 and is in contact with the skid buttons 10a and 12a may be lowered. .

  Therefore, in the present embodiment, the plurality of heat transfer promotion devices 14 arranged below the combustion burner 8 absorb the infrared rays diffused from the combustion burner 8 and generate radiant heat. In particular, radiant heat is induced obliquely upward from the two heat transfer plates 14a and 14b. As described above, when radiant heat is induced obliquely upward from the two heat transfer plates 14a and 14b of each heat transfer promoting device 14, the vicinity of the contact portion of the slab S that is in contact with the skid buttons 10a and 12a. Will be heated locally.

Thereby, the temperature in the vicinity of the contact portion of the slab S is hardly changed from the temperature of the other portion of the slab S, and no skid mark is generated in the slab S after extraction.
Therefore, in the present embodiment, the heat transfer promotion device 14 disposed below the combustion burner 8 absorbs infrared rays radiated from the flame of the combustion burner 8 to generate radiant heat, and this radiant heat is generated in the contact portion of the slab S. Since it is heated locally by inducing toward the vicinity, as in the past, a method of extending the in-furnace time of the material to be heated, such as increasing the furnace length or slowing the conveying speed, Compared with a method in which a large number of combustion burners and pipes are arranged in the furnace, an increase in fuel consumption and an increase in equipment costs can be suppressed, and production efficiency can be maintained.

Next, what is shown in FIG. 4 shows another embodiment of the heat transfer promoting device.
The heat transfer promoting device 20 of the present embodiment includes a refractory base 22 and a heat radiation layer 24 provided on the upper surface of the refractory base 22.
The refractory base 22 is arranged in a mountain shape in which a ridge line r extends in the furnace length direction, and two planar substrates 22a and 22b extend obliquely downward at a predetermined inclination angle from the ridge line r. 4 is supported by a support member 16 rising from 4.

Further, the heat radiation layer 24 is provided on the upper surfaces of the substrates 22 a and 22 b of the refractory base 22. The thermal radiation layer 24 is provided by applying a thermal radiation paint containing, for example, titanium oxide on the substrates 22a and 22b. The heat radiation layer 24 has a property of absorbing all wavelengths of infrared rays and generating high energy radiant heat.
When the heat transfer promoting device 20 having the above-described configuration is disposed below the combustion burner 8, the heat radiation layer 24 absorbs all wavelengths of infrared rays diffused from the combustion burner 8, and generates high-energy radiant heat.

And high energy radiant heat is induced | guided | derived toward diagonally upward from the heat radiation layer 24 provided in the upper surface of the board | substrates 22a and 22b of the refractory base part 22. FIG. Thereby, the contact part vicinity of the slab S which is contacting the skid buttons 10a and 12a is rapidly heated by the high energy radiant heat from the heat-transfer promotion apparatus 20. FIG.
Thereby, also in this embodiment, the temperature of the contact part vicinity of the slab S hardly changes with the temperature of the other part of the slab S, and a skid mark does not generate | occur | produce in the slab S after extraction.

Therefore, in the present embodiment, the heat radiation layer 24 of the heat transfer promoting device 22 disposed below the combustion burner 8 absorbs all wavelengths of infrared rays radiated from the flame of the combustion burner 8 to generate high energy radiant heat. Therefore, the vicinity of the contact portion of the slab S blocked by the fixed skid beam 10 and the movable skid beam 12 can be efficiently heated.
In the heat transfer promoting device 20 described above, the heat radiating layer 24 is provided by applying a heat radiating paint on the upper surfaces of the substrates 22a and 22b of the refractory base 22, but the sheet-like heat radiating material is formed on the substrates 22a and 22b. Even if it is provided on the upper surface of 22b, the same effect can be obtained.

  Here, FIG. 5 shows the amount of heat input to the vicinity of the contact portion of the slab S (near the portion in contact with the skid buttons 10a and 12a) and the amount of heat input other than the contact portion (position away from the contact portion). It is the experimental result which compared the comparison with the walking beam type continuous heating furnace which concerns on this invention, and the conventional walking beam type continuous heating furnace. Note that the shape factor on the vertical axis in FIG. 5 is an index of the amount of heat input to the slab S. When the shape factor is high, the heating capacity for the slab S increases, and when the shape factor is low, the slab S This means that the heating capacity against is decreasing.

  From the experimental results of FIG. 5, the conventional walking beam type continuous heating furnace has a large difference in form factor between the vicinity of the contact portion of the slab S and the portion other than the contact portion. Since the difference in the shape factor between the contact portion of the slab S and the non-contact portion is small in the continuous heating furnace, it is clear that the heat transfer promotion device locally heats the vicinity of the contact portion of the slab S It is.

It is sectional drawing of the furnace width direction which shows the walking beam type continuous heating furnace which concerns on this invention. It is sectional drawing of the furnace length direction which shows the walking beam type continuous heating furnace which concerns on this invention. It is a figure which shows the positional relationship of the principal part of the walking beam type continuous heating furnace which concerns on this invention. It is a figure which shows other embodiment of the heat-transfer promotion apparatus arrange | positioned at the walking beam type continuous heating furnace which concerns on this invention. It is the figure which compared the heating capability with respect to a to-be-heated material in the conventional walking beam type continuous heating furnace and the walking beam type continuous heating furnace which concerns on this invention.

Explanation of symbols

2 furnace wall 4 hearth 6 furnace body (heating furnace)
8 Combustion Burner 10 Fixed Skid Beam 10a Skid Button 12 Movable Skid Beam 12a Skid Button 14, 20 Heat Transfer Promoters 14a, 14b Heat Transfer Plate (Flat Plate)
22 Refractory base (refractory)
22a, 22b Substrate (flat plate)
24 Thermal radiation layer S Slab (material to be heated)

Claims (6)

A heat transfer facilitating device that locally heats a specific part of a material to be heated in a heating furnace, which absorbs infrared rays that are dissipated from the flame of a combustion burner, and generates radiant heat. A heat transfer promotion device for a heating furnace, which is disposed at a predetermined position in the heating furnace so as to face.   2. The heat transfer promotion device for a heating furnace according to claim 1, wherein the heat transfer promotion device is formed of a refractory that generates radiant heat by absorbing infrared rays.   The heat transfer promoting device for a heating furnace according to claim 1, wherein the member has thermal radiation.   The heat transfer promoting device for a heating furnace according to claim 3, comprising a refractory and a heat radiation layer provided on a surface of the refractory facing the specific portion. 5. A walking in which a combustion burner is disposed below a skid beam that supports and conveys a material to be heated, and the heat transfer promoting device according to any one of claims 1 to 4 is disposed on a hearth side below the combustion burner. In beam type continuous heating furnace,
The specific part of the material to be heated is a vicinity of the support part that supports the material to be heated of the skid beam, and the vicinity of the support part is locally heated by the heat transfer promoting device. Walking beam type continuous heating furnace equipped with a promotion device.   The heat transfer promotion device is arranged in a mountain shape so that a ridge line extends in the furnace length direction, and two flat plates extend obliquely downward at a predetermined inclination angle from the ridge line, The walking beam type continuous heating furnace provided with the heat transfer promoting device according to claim 4, wherein a flat plate faces the vicinity of the support portion.

Images