JP2011230144A - Flashing device and flashing method for descaling injection water - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flashing device and a flashing method for descaling injection water, capable of preventing a flaw from being generated on a rolled material surface, capable of preventing water from being splashed or intruding to/into an electric facility or the like installed in the immediate vicinity of a descaling device, and capable of narrowing an installation space.SOLUTION: The flashing device for the descaling injection water includes: a throating plate 2 arranged with a fixed clearance g to the rolled material S1 surface, to recover bound water 1b after descaled, in a rolling-directional upstream of a descaling water injection nozzle 1 for removing a scale on the rolled material S1 surface, by the injection water 1a; and a flashing spray 3 for injecting flashing spray water 3a toward the clearance g between a lower end of the throating plate 2 and the rolled material S1 surface, in a rolling-directional upstream of the throating plate 2. The flaw is precluded from being generated on the rolled material S1 surface, and the descaling injection water is prevented from flowing or being splashed into/to an electric facility or the like side of disliking water, by providing the clearance g with respect to the rolled material S1 surface, to dispose the throating plate 2 and the flashing spray 3.

Description

The present invention relates to a descaling water draining device and a draining method for removing scale generated on the surface of a hot rolled material.

In the hot rolling line, oxidized scale is generated on the surface of the high-temperature rolled material, and if rolled as it is, wrinkles enter the surface of the rolling roll and the surface of the rolled material and the quality is deteriorated. Therefore, in order to remove the scale before the rolling material bites into the rolling roll of the rolling mill, a descaling facility for removing the scale by spraying high-pressure water onto the surface of the rolling material is provided on the upstream side of the rolling mill.

The behavior of spray water from the descaling equipment after the scale is removed by colliding with the surface of the rolled material becomes a problem. One is bound water that bounces on the surface of the rolled material, and the other is plate water that flows along the surface of the rolled material to the upstream side in the rolling direction. Such water causes the temperature of the rolled material to decrease by flowing on the surface of the rolled material.

For this reason, conventionally, a plate-shaped scraper (draining plate) is installed on the downstream side (upstream side when viewed from the rolling direction) in the spray water flow direction in contact with the surface of the rolled material, and the spray water is drained and sprayed. Facilities for collecting water are installed. However, in order to generate wrinkles on the surface of the rolled material by contact with the lower end of the draining plate, there is a problem that it is difficult to apply such a draining method with a surface quality strict material. Therefore, various draining devices have been devised.

For example, in Patent Document 1, a slight gap is provided on the upstream side of the descaling spray water injection nozzle that removes the scale generated on the surface of the hot rolled material by injecting high pressure water from the surface of the hot rolled material. A descaling water draining device is disclosed in which a scraper for recovering jet water is disposed, and a scraper for recovering the remaining spray water in contact with the surface of the hot-rolled material is disposed further upstream of the scraper. Yes.

Further, in Patent Document 2, a high-pressure water having an injection pressure of 10 MPa or more is injected from an injection nozzle to remove scale generated on the surface of the rolled material, and a scraper installed on the upstream side of the rolling material conveyance line of the injection nozzle. A descaling method for recovering high-pressure water, wherein a relationship between the distance from the rolled material and the amount of high-pressure water splashing upward at the scraper position is obtained in advance, and the recovery rate of high-pressure water is determined based on the relationship. A descaling method is disclosed in which the gap between the lower end of the scraper and the surface of the rolled material is adjusted to 80% or more.

Furthermore, in Patent Document 3, a descaling spray water injection nozzle for removing scale floating on the surface of the rolled material is provided on the inlet side of the hot rolling mill, and spray water is provided upstream of the descaling spray water spray nozzle. There is disclosed a descaling apparatus for draining descaling water, in which a scraper to be recovered is disposed with a slight gap from the surface of the plate, and a draining roll is provided on the upstream side of the scraper to contact the surface of the plate.

Japanese Utility Model Publication No. 5-44304 JP 2006-35275 A Japanese Utility Model Publication No. 61-107409

In the draining device disclosed in the above-mentioned Patent Document 1, the draining plate in the second stage remains in contact with the rolled material, and there is a high possibility that surface flaws will occur. It becomes difficult to apply.

In the descaling method disclosed in the above-mentioned Patent Document 2, the installation position and angle of the draining plate are optimized. However, as long as there is a gap between the draining plate and the rolled material, it is not possible to drain completely.

In any draining device, the on-board water flows to the draining roll and draining side of the second and subsequent stages through the gap between the first stage draining plate and the surface of the rolled material, causing the temperature of the rolled material to decrease. Or splashed water may enter the electrical equipment installed near the descaling equipment and cause a failure.

In the draining device disclosed in the above-mentioned Patent Document 3, in order to drain the water on the plate flowing from the gap between the rolled material and the draining plate to the upstream side in the rolling direction, the second draining roll, Draining spray is arranged, and although it is thought that drainage is sufficient, a large installation space is required. For example, when an edge heater that reheats the rolled material that has come out of the roughing mill is installed on the entry side of the finishing mill, it is installed in a constrained space between the edge heater and the finishing mill. If the installation space is large, there is a problem that the installation becomes difficult. Further, in this draining device, water stays at the draining roll inlet, and the temperature of the rolled material is inevitably lowered.

In addition, instrumentation equipment such as temperature sensors installed near the descaling equipment and electrical equipment such as edge heaters (hereinafter, these may be collectively referred to as “electric equipment etc.”) It is necessary to promptly collect the water on the board and the scattered water because the water may enter and cause a failure.

Therefore, the present invention does not generate wrinkles on the surface of the rolled material, and can prevent water from scattering and entering even when electrical equipment that dislikes water is in the immediate vicinity of the descaling device, and further reduces the installation space. An object of the present invention is to provide a draining device and a draining method for descaling jet water.

In order to solve the above-described problem, the first configuration of the present invention is a bouncing from the rolled material after descaling to the upstream side in the rolling direction of the descaling water injection nozzle that removes the scale generated on the surface of the rolled material with spray water. In order to collect water, a draining plate arranged with a certain gap from the surface of the rolled material, and on the upstream side in the rolling direction of the draining plate, draining toward the gap between the lower end of the draining plate and the surface of the rolled material. A descaling water draining device comprising a draining spray installed so as to eject spray water.

In this first configuration, by providing a draining plate with a certain gap from the surface of the rolled material, wrinkles are not generated on the surface of the rolled material, and draining spray water is drained from the draining spray to the lower end of the draining plate. Since water is ejected toward the gap between the surface of the rolled material and the surface of the rolled material, the water on the plate does not scatter or flow into the upstream side in the rolling direction in which electrical equipment that dislikes water is installed. Furthermore, since the draining spray can be installed in the vicinity of the draining plate, the installation space of the entire draining device can be reduced, and the installation can be easily performed in a narrow space between the edge heater and the finishing mill entrance side. In the present specification, the “upstream side in the rolling direction” means the upstream side in the traveling direction of the rolled material.

The second configuration of the present invention is the descaling spray water draining device, wherein the draining plate includes an angle adjusting mechanism that automatically adjusts the angle according to the thickness of the rolled material. Since the thickness of the rolled material changes every time, the angle of the drained plate is adjusted so that the gap between the drained plate and the surface of the rolled material is kept constant, so that the drained plate does not touch the rolled material, Drainability can be ensured without generating wrinkles on the plate surface regardless of the thickness of the rolled material.

A third configuration of the present invention is a draining method using the descaling spray water draining device described above, wherein the descaling spray water flow rate and the size of the jet pressure are determined on the surface of the rolling material. The descaling spray water draining method is characterized in that the condition is set such that the on-board water is prevented from flowing upstream from the position of the gap between the lower end of the draining plate and the surface of the rolled material.

In this third configuration, when the water on the plate, which is a part of the descaling jet water, is prevented from flowing along the surface of the rolled material to the upstream side in the rolling direction of the rolled material, By setting the collision point of water and drained spray water to the downstream side (descaling spray water injection nozzle side) of the gap between the lower end of the draining plate and the surface of the rolled material, the draining plate becomes a barrier and splashes water. Can be effectively prevented from entering the electrical equipment side.

According to the present invention, since the draining plate is not in contact with the rolled material, the surface of the rolled material can be prevented. In addition, in order to block the water on the plate that travels on the surface of the rolled material upstream of the rolling direction by the draining spray, water to the electrical equipment such as an instrumentation sensor or induction heating furnace that dislikes the water installed in the immediate vicinity of the draining plate Intrusion can be prevented. Furthermore, since it is composed of a draining plate and a draining spray, the installation space can be reduced.

It is the schematic which shows arrangement | positioning of the draining apparatus of the descaling jet water which concerns on embodiment of this invention. It is an enlarged view of the draining device portion of the descaling jet water according to the embodiment of the present invention. It is an enlarged view which shows the position of the collision point by the pressure of the draining spray of the descaling apparatus for draining the descaling water according to the embodiment of the present invention. It is an enlarged view which shows the position of the collision point by the pressure of the draining spray of the descaling apparatus for draining the descaling water according to the embodiment of the present invention. It is an enlarged view which shows the position of the collision point by the pressure of the draining spray of the descaling apparatus for draining the descaling water according to the embodiment of the present invention. It is a graph which shows the relationship between the drain spray pressure by Experiment 1, and a collision point position. It is a graph which shows the relationship between the draining spray flow volume by Experiment 1, and a pressure. It is a graph which shows the drainage ensuring conditions by Experiment 2.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. As shown in FIG. 1, the descaling water draining device of the present embodiment further rolls the descaling water jet nozzle 1 installed on the upstream side in the rolling direction of the finishing mill 10 composed of rolling stands F1 to F7. A draining plate 2 that is provided on the upstream side in the direction and downstream of the induction heating device (edge heater) 11 and collects the spray water sprayed from the descaling water spray nozzle 1, the lower end portion of the draining plate 2, and rolling It is comprised by the draining spray 3 which directs the clearance gap vicinity between material S1 surface, and ejects draining spray water.

FIG. 2 shows an enlarged view of the draining device portion. High-pressure (for example, 15 MPa) spray water 1a irradiated on the rolled material S1 at an angle of 5 ° to 15 ° from the descaling water spray nozzle 1 removes the scale on the surface of the rolled material S1, and the bound water 1b is in an inclined state. It passes along the surface of the draining board 2 installed in and is discharged to the side part through a ridge (not shown). The draining plate 2 is installed with a certain gap g (for example, 10 to 15 mm) so as not to scratch the surface of the rolled material S1. Since the gap g changes when the thickness of the rolled material S1 changes, an angle adjusting mechanism (not shown) is provided so that a constant gap g can be secured even if the thickness of the rolled material S1 changes. That is, when the thickness of the rolled material S1 is output from the process computer, the angle adjusting mechanism is operated to automatically adjust the angle of the draining plate 2 so that a preset gap g can be secured.

Now, a part of the jet water 1a from the descaling water jet nozzle 1 is blocked by the draining plate 2 as bounce water 1b that bounces off the surface of the rolled material S1, while the other part travels on the surface of the rolled material S1. The on-board water 1c flows in the direction opposite to the rolling direction. The on-board water 1c passes through the gap g between the lower end portion of the draining plate 2 and the surface of the rolled material S1 and flows into the upstream side of the draining plate 2 in the rolling direction. In order to prevent this, the draining spray water 3a ejected from the draining spray 3 is used.

In order to protect the electrical equipment such as the induction heating device 11 installed on the upstream side in the rolling direction of the finishing mill 10, it is necessary that the on-board water 1c does not flow into the upstream side in the rolling direction than the draining plate 2. is there. Therefore, the pressure of the draining spray water 3a ejected from the draining spray 3 so that the collision point P between the draining spray water 3a and the on-board water 1c is on the downstream side (as viewed from the rolling direction) of the draining plate 2; The flow rate was determined by the following experiment.

<Experiment 1> Purpose: Formulate a draining spray condition range where the collision point P is on the descaling side (finishing mill side) with respect to the draining plate 2 from experimental results simulating actual equipment. Condition: The interval L1 between the mounting shaft 2a of the draining plate 2 and the draining spray 3 in FIG. 2 is 120 mm, the interval L2 between the descaling water spray nozzle 1 and the draining spray 3 is 1750 mm, the lower end of the draining plate 2 and the rolling material The gap g between the surface of S1 was 10 to 15 mm, and the pressure of the spray water 1a sprayed from the descaling water spray nozzle 1 was 15 MPa. Further, the angle θ1 of the descaling water jet nozzle 1 is 15 °, the height H1 from the rolled material S1 is 0.25 m, the angle θ2 of the draining spray 3 is 25 °, and the height H2 from the rolled material S1 to the nozzle is 0. .17 m. Experimental method: The position of the collision point P when the flow rate of the spray water 3a from the draining spray 3 was 20 L / min (at 0.3 MPa) and the ejection pressure was 1 MPa, 3 MPa, and 5 MPa was measured. As for the position of the collision point P, the scaled spray water and the draining spray collision part were photographed, and the position where the descaled spray water was pushed back and stayed was measured on the image. In addition, in order to make it easy to see the flow of both the descaling spray water and the draining spray water, water obtained by coloring the draining spray with water-based ink was used.

Experimental results: When the spraying pressure of the spray water 3a from the draining spray 3 was 1 MPa, the collision point P was 130 mm (−130 mm) from the position of the gap g to the upstream side in the rolling direction as shown in FIG. When the ejection pressure was 3 MPa, the collision point P was exactly the position of the gap g (0 mm) as shown in FIG. When the ejection pressure was 5 MPa, the collision point P was 100 mm (+100 mm) downstream from the position of the gap g as shown in FIG. When the flow rate of the spray water 3a from the draining spray 3 was set to 8 L / min (at 0.3 MPa), the position of the collision point P was measured, and when the ejection pressure was 1 MPa, −180 mm, and at 3 MPa, − At 50 mm and 5 MPa, it was +50 mm.

FIG. 6 is a graph in which the ejection pressure and the position of the collision point P are plotted while changing the flow rate. When the three points of the ejection pressure x and the collision point position y at each flow rate are connected by a straight line, it can be seen that the straight line has the following relationship. When the flow rate is 20 L / min, y = 57.5x-182.5 (1) equation When the flow rate is 8 L / min, y = 57.5x-232.5 (2) equation (1) equation And (2) are integrated as a function of the flow rate a, the following expression (3) is obtained. y = 57.5x + 4.17a-265.83 (3) formula

From the equation (1), x (ejection pressure) at which the position of the collision point P is 0 is found to be x = 3.174 (at a flow rate of 20 L / min). Further, when x (ejection pressure) at which the collision point position is 0 is obtained from the equation (2), x = 4.043 (when the flow rate is 8 L / min). From this relationship, the relationship between the flow rate at which the collision point position becomes 0 (new x) and the ejection pressure (new y) is expressed as follows: y = −0.073x + 4.62 as in the straight line of the graph shown in FIG. ... expressed by equation (4). Since the flow rate and pressure of the spray water 3a from the draining spray 3 are required to be such that the position of the collision point P is ≧ 0, the flow rate and pressure in the region above the straight line shown in FIG. The condition will be met.

<Experiment 2> Purpose: To confirm whether or not the relationship of Formula (4) formulated from the result of Experiment 1 simulating actual equipment is generally established. Conditions: As in Experiment 1, Experimental method: Experiments were conducted on the following draining spray conditions (Verification Examples 1 to 6) with different pressures and flow rates, and the validity of the spray condition range was verified.

FIG. 8 shows a plot of the results of Experiment 2 as the relationship between flow rate and pressure. A negative impact point was evaluated as x (unsuitable), and 0 or higher was evaluated as ◯. Although the verification examples 1 to 3 are in a region below the straight line of the equation (4), the verification examples 4 to 6 are in a region above the straight line of the equation (4), and the relationship of the equation (4) is appropriate. I was able to prove that.

The relationship of equation (4) is based on the above conditions in Experiment 1. If the conditions change, the experiment is performed under those conditions, and the relationship between the flow rate and pressure at which the collision point is 0 or more. Can be obtained a relational expression similar to the expression (4).

As described above, in the apparatus according to the present embodiment, the bound water is stopped by the draining plate, and the water on the plate is optimized by optimizing the flow rate and pressure of the spray water from the draining spray provided immediately upstream in the rolling direction of the draining plate. It can prevent flowing to the upstream side in the rolling direction. Moreover, since the draining apparatus of this Embodiment can be comprised only with a draining board and spray water, an installation space is small and can be installed without a problem even when the space between an edge heater and a finishing rolling mill does not have much room.

In addition, although the descaling water draining device and the descaling water spray nozzle 1 according to the present embodiment have been shown installed on the upstream side in the rolling direction of the finishing mill 10 including the rolling stands F1 to F7, Without being limited to the installation position, it can also be installed in other places of the hot rolling line.

The present invention does not generate wrinkles on the surface of the rolled material, and can prevent water scattering and intrusion even when electrical facilities that dislike water are in the immediate vicinity of the descaling device, and further reduce the installation space As a draining apparatus and draining method for descaling spray water that can be used, it can be suitably used particularly for rolling a surface quality strict material.

DESCRIPTION OF SYMBOLS 1 Descaling water injection nozzle 1a Spray water 1b Bound water 1c Plate water 2 Drain plate 2a Mounting shaft 3 Drain spray 3a Spray water 10 Finishing rolling mill 11 Induction heating device (edge heater) S1 Rolling material g Gap

Claims (3)

In order to recover the bound water that bounces off the descaled rolled material upstream of the descaling water jet nozzle in the rolling direction, the scale generated on the surface of the rolled material is removed with spray water. A draining board provided and arranged;
A descaling spray water provided with a drain spray installed on the upstream side in the rolling direction of the drain plate so as to eject the drain spray water toward the gap between the lower end of the drain plate and the surface of the rolled material. Drainer.   The desiccant spray water draining device according to claim 1, wherein the draining plate includes an angle adjusting mechanism that automatically adjusts the angle according to the thickness of the rolled material.   A draining method using the descaling spray water draining device according to claim 1, wherein the flow rate of the draining spray water and the magnitude of the jet pressure are determined based on the surface water of the descaling jet water that travels on the surface of the rolled material. A method for draining descaling spray water, characterized in that the conditions are set so as to prevent the flow from the lower end of the draining plate and the surface of the rolled material to the upstream side in the rolling direction.