JP2003181516A - Method and device for spraying rolling lubricant - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and a device for spraying a rolling lubricant having uniform rolling oil concentration to a reduction roll by eliminating the consumption of the rolling oil by adjusting the number of nozzles to spray the rolling lubricant that is a mixture of the rolling oil and water in accordance with the width of the metal plate subjected to rolling, and at the same time, by maintaining the flow of the mixture constant to circulate inside a circulating flow channel even if the number of nozzles to spray the rolling lubricant is changed. <P>SOLUTION: In the method for spraying the rolling lubricant through a plurality of spray nozzles provided in the rotating shaft direction of the reduction roll, the number of the spray nozzles to spray the rolling lubricant is changed in accordance with the width of the metal plate available for rolling, and, in accordance with the number of spray nozzles to spray the rolling lubricant, the opening area of a throttling aperture provided in the inlet side piping of a nozzle header is changed, by which the flow of the rolling lubricant to circulate the circulating flow channel provided inside the nozzle header where spray nozzles are provided is maintained constant. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for rolling a metal sheet such as cold tandem rolling of a steel sheet, using a rolling lubricant prepared by mixing rolling oil and water having no compatibility (property of mutual melting) with each other. And a method and device for injecting into a rolling roll.

[0002]

2. Description of the Related Art A rolling roll for cold tandem rolling a metal plate is subject to wear and surface defects due to friction with the metal plate used for rolling. Therefore, the surface of the rolling roll is regularly ground or the rolling roll is exchanged for operation. Grinding or replacement of the rolling rolls as described above increases the roll unit and increases the manufacturing cost of the metal sheet.

Therefore, a rolling lubricant is used for the purpose of reducing the coefficient of friction between the rolling roll and the metal plate. Generally, the rolling lubricant is a mixed liquid in which rolling oil and water which are not compatible with each other are mixed. When a rolling lubricant is supplied between the rolling roll and the metal plate, not only the friction coefficient between the rolling roll and the metal plate is reduced but also the rolling load is reduced, so that the driving force of the rolling roll can be reduced. As a result, in addition to the reduction of the roll intensity, there is also the effect of reducing the power intensity.

FIG. 3 is a sectional view schematically showing an example of a conventionally known rolling lubricant injection device. The arrow in FIG. 3 indicates the direction in which the rolling lubricant, which is a mixed liquid of rolling oil and water (also referred to as dilution water), flows. The rolling oil and the dilution water are mixed by a mixing device (not shown) and then supplied to the nozzle header 1 through the nozzle header inlet side pipe 2. For the purpose of increasing the flow rate of the mixed liquid supplied from the nozzle header inlet side pipe 2 to the nozzle header 1, the throttle member 9 is provided in the discharge hole of the nozzle header inlet side pipe 2.
Is provided. In this way, the mixed liquid of the rolling oil and the diluting water is sprayed from the spray nozzles 4a, 4b and 4c to the rolling roll (not shown) through the circulation passage 3 provided in the nozzle header 1.

The surplus mixed liquid is spray nozzles 4a, 4b,
It is not jetted from 4c and circulates through the circulation flow path 3 to the outlet side of the nozzle header inlet side pipe 2 discharge hole. Since the flow velocity of the mixed liquid supplied from the nozzle header inlet side pipe 2 to the nozzle header 1 is increased by the throttle member 9 arranged in the nozzle header inlet side pipe 2 discharge hole, the flow rate at the outlet side of the discharge hole is increased. Negative pressure occurs. Therefore, the mixed liquid that has circulated through the circulation flow path 3 is entrained in the mixed liquid that is supplied from the nozzle header entry side pipe 2 to the nozzle header 1, passes through the circulation flow path 3 again, and is spray nozzle 4a. , 4b, 4c are injected.

The nozzle header 1 is provided with a plurality of spray nozzles 4a, 4 in the direction of the rotating shaft of a rolling roll (not shown).
b and 4c are provided. When the plate width of the metal plate (not shown) used for rolling changes, the number of spray nozzles 4 for injecting the mixed liquid is adjusted by opening and closing the valves 5a and 5b according to the plate width. That is, when the plate width is wider than the distance between the spray nozzles 4a, the valves 5a and 5b are opened and the mixed liquid is sprayed from all spray nozzles 4a, 4b and 4c to the rolling roll.

When the plate width is narrower than the space between the spray nozzles 4a and wider than the space between the spray nozzles 4b,
Close valve 5a and open valve 5b to spray nozzle 4
The liquid mixture is sprayed from b and 4c onto the rolling rolls. Furthermore, if the plate width is narrower than the space between the spray nozzles 4b, the valve 5
The a and 5b are closed, and the mixed liquid is sprayed from the spray nozzle 4c to the rolling roll.

In this way, the spray nozzles 4a, 4b, which inject the mixed liquid in accordance with the plate width of the metal plate to be rolled,
The consumption of rolling lubricant can be reduced by adjusting the number of 4c and changing the amount of the mixed liquid used. However, when the valves 5a and 5b are opened and closed to inject the mixed liquid onto the rolling rolls, the pressure loss in the circulation passage 3 changes. Figure 3
In this injection device, the inner diameter of the throttle member 9 arranged in the discharge port of the nozzle header inlet side pipe 2 is constant regardless of the number of spray nozzles 4a, 4b, 4c for injecting the mixed liquid. Therefore, when the pressure loss in the circulation channel 3 changes, the flow rate of the mixed liquid in the circulation channel 3 changes.

When using a mixed liquid of rolling oil and dilution water which are not compatible with each other, closing the valves 5a and 5b causes an increase in pressure loss in the circulation passage 3 and causes a decrease in pressure in the circulation passage 3. As a result of the decrease in the flow rate of the mixed liquid, the mixed liquid stays in the circulation passage 3 (particularly in the corner portion), and the rolling oil and the diluting water are easily separated. Then, the rolling oil and the dilution water separated in the circulation passage 3 are
When it is caught in the mixed liquid supplied from the nozzle header inlet side pipe 2 to the nozzle header 1 and again passed through the circulation flow path 3 and sprayed from the spray nozzles 4a, 4b, 4c to the rolling roll, The concentration of rolling oil (in the rolling lubricant) becomes non-uniform. When a rolling lubricant having a non-uniform concentration of rolling oil is sprayed on a metal plate, rolling causes various problems such as deformation of the metal plate, surface defects, and seizure.

[0010]

SUMMARY OF THE INVENTION The present invention solves the above problems, and adjusts the number of spray nozzles for injecting a rolling lubricant according to the width of a metal plate used for rolling to achieve rolling lubrication. In addition to reducing the consumption of the lubricant, even if the number of spray nozzles that inject the rolling lubricant changes, the flow rate of the rolling lubricant that circulates in the circulation passage is kept constant, and the concentration of rolling oil is uniform. It is an object to provide a method and a device for injecting rolling lubricant.

[0011]

The present invention provides a rolling lubricant injection method for injecting a rolling lubricant through a plurality of spray nozzles arranged in the rotational axis direction of a rolling roll.
The number of spray nozzles that inject rolling lubricant is changed according to the width of the metal plate used for rolling, and the throttle provided in the inlet pipe of the nozzle header is changed according to the number of spray nozzles that inject rolling lubricant. This is a rolling lubricant injection method in which the opening area of the holes is changed to maintain a constant flow rate of the rolling lubricant circulating in the circulation passage provided in the nozzle header in which the spray nozzle is arranged.

According to the present invention, a nozzle header having a plurality of spray nozzles in the direction of the rotary axis of a rolling roll and having a circulation passage through which a rolling lubricant circulates, and a flow of the rolling lubricant injected from the spray nozzles. A valve that opens and closes the path,
The rolling lubricant injection device is provided with a variable throttle device that changes the opening area of the throttle hole provided in the nozzle header inlet side pipe according to the number of spray nozzles that inject the rolling lubricant.

[0013]

1 is a sectional view schematically showing an example of a rolling lubricant injection device to which the present invention is applied. Figure 1
The arrow inside indicates the direction in which the rolling lubricant, which is a mixture of rolling oil and dilution water, flows. 2 is a sectional view taken along the line AA in FIG. The incompatible rolling oil and dilution water are mixed by a mixing device (not shown) and then supplied to the nozzle header 1 through the nozzle header inlet side pipe 2. In the present invention, the mixing device for mixing the rolling oil and the diluting water is not limited to a specific structure, and a conventionally known mixing device is used.

In the present invention, as will be described later,
The number of spray nozzles 4a, 4b, 4c for injecting the rolling lubricant is adjusted according to the width of the metal plate used for rolling. Therefore, even if the flow velocity of the rolling lubricant supplied from the nozzle header inlet side pipe 2 to the nozzle header 1 is increased and the number of the spray nozzles 4a, 4b, 4c for injecting the rolling lubricant is changed, the rolling lubricant is also changed. A variable expansion device 6 is arranged in the nozzle header inlet side pipe 2 so that the air flows in a circulating flow path 3 provided in the nozzle header 1 at a constant flow rate.

As shown in FIG. 2, since the variable throttle device 6 is rotatably arranged around the rotary shaft 7, the number of spray nozzles 4a, 4b, 4c for injecting the rolling lubricant changes. However, by rotating the variable expansion device 6 to change the opening area of the expansion hole 8, the flow rate of the rolling lubricant circulating in the circulation passage 3 can be maintained constant. In this way, the rolling lubricant, which is a mixed liquid of rolling oil and dilution water, passes from the spray nozzles 4a, 4b, 4c to the rolling rolls (not shown) through the circulation passage 3 provided in the nozzle header 1. Is jetted.

The surplus rolling lubricant is spray nozzle 4a,
It is not jetted from 4b and 4c, and circulates through the circulation flow path 3 to the outlet side of the nozzle header inlet side pipe 2 discharge hole. Since the flow velocity of the rolling lubricant supplied from the nozzle header inlet side pipe 2 to the nozzle header 1 is increased in the nozzle header inlet side pipe 2 discharge hole, a negative pressure is generated at the outlet side of the discharge hole. Therefore, the rolling lubricant that has circulated through the circulation passage 3 is caught in the rolling lubricant supplied from the nozzle header inlet side pipe 2 to the nozzle header 1, and passes through the circulation passage 3 again to spray. It is ejected from the nozzles 4a, 4b, 4c.

The nozzle header 1 has a plurality of spray nozzles 4a, 4a in the direction of the rotation axis of a rolling roll (not shown).
b and 4c are provided. When the width of a metal plate (not shown) used for rolling changes, spray nozzles 4a, 4b, which open and close valves 5a, 5b according to the plate width to inject rolling lubricant,
Adjust the number of 4c. In other words, the plate width is the spray nozzle 4a
If it is wider than the interval, the valves 5a and 5b are opened, and the rolling lubricant is sprayed from the spray nozzles 4a, 4b and 4c to the rolling rolls.

When the plate width is narrower than the space between the spray nozzles 4a and wider than the space between the spray nozzles 4b,
Close valve 5a and open valve 5b to spray nozzle 4
Rolling lubricant is sprayed onto the rolling rolls from b and 4c. further,
When the plate width is narrower than the space between the spray nozzles 4b, the valves 5a and 5b are closed, and the rolling lubricant is sprayed from the spray nozzle 4c to the rolling roll.

When injecting the rolling lubricant, a valve
When the 5a and 5b are opened and closed, the pressure loss in the circulation flow path 3 changes. However, the pressure loss in the circulation channel 3 does not change during rolling of a single metal plate, but changes when rolling metal plates having different plate widths. In addition, the pressure loss in the circulation channel 3 is
It does not change linearly, but changes gradually. Therefore, a variable expansion device 6 is arranged in the nozzle header inlet side pipe 2 to keep the pressure loss in the circulation flow path 3 constant.

That is, the variable throttle device 6 includes valves 5a,
Three types of throttle holes 8 having an opening area proportional to the amount of change in pressure loss in the circulation flow path 3 due to opening / closing of 5b are provided. Then, according to the opening and closing of the valves 5a and 5b when the width of the metal plate used for rolling changes, the variable throttle device 6 is rotated to select the throttle hole 8 having an appropriate opening area, thereby circulating The pressure loss in the passage 3 is kept constant, and the flow rate of the rolling lubricant in the circulation passage 3 is kept constant.

In this way, the spray nozzle 4a for injecting the rolling lubricant according to the width of the metal plate used for rolling,
The consumption of rolling oil can be reduced by adjusting the number of 4b and 4c and changing the amount of rolling lubricant used. Moreover,
Since the flow rate of the rolling lubricant in the circulation passage 3 can be kept constant, it is possible to suppress the separation of the incompatible rolling oil and the diluting water and to inject the rolling lubricant having a uniform concentration to the rolling rolls.

The opening area of the throttle holes 8 and the number of the throttle holes 8 are values set according to the number of the spray nozzles 4a, 4b, 4c and the valves 5a, 5b. Not limited. Further, here, the example of opening and closing the valves 5a and 5b (that is, adjustment in three stages) has been described, but the present invention does not limit the number of valves to be opened and closed to a specific number. For example, when the total number of valves to be opened and closed is six (that is, four-stage adjustment), the variable throttle device 6 is provided with four kinds of throttle holes 8 each having a different opening area, so that the pressure in the circulation passage 3 is reduced. The loss can be kept constant, and the flow rate of the rolling lubricant in the circulation passage 3 can be kept constant.

For the purpose of preventing leakage of the rolling lubricant, it is preferable to seal the sliding surface between the nozzle header inlet side pipe 2 and the variable throttle device 6. In the present invention, the sealing means is not limited to a particular material or structure, as long as it can prevent the rolling lubricant from leaking out. For example, a conventionally known packing such as packing can be used.

If the temperature of the diluting water mixed with the rolling oil is less than 40 ° C., the rolling oil and the diluting water are not sufficiently mixed and the concentration of the rolling oil becomes non-uniform. On the other hand, if the temperature of the diluting water exceeds 50 ° C, it becomes difficult to separate the rolling lubricant when it is sprayed onto the rolling rolls, and the amount of rolling oil deposited on the rolling rolls decreases.
Therefore, the temperature of the diluting water preferably satisfies the range of 40 to 50 ° C.

When the present invention is applied to a large quantity of products such as cold rolled steel plates, a great economic effect can be expected.

[0026]

EXAMPLE Using the rolling lubricant injection device shown in FIG.
The flow rate of the rolling lubricant and the concentration of the rolling oil were investigated by injecting the rolling lubricant, which is a mixed solution of incompatible rolling oil and dilution water. That is, palm oil is used as the rolling oil, and the temperature is 45 ° C.
A mixed solution prepared by dispersing palm oil as an emulsion with the dilution water of was used as a rolling lubricant. The concentration of palm oil is 10
It was mass%. The spray nozzles 4a, 4b and 4c are all designed so that the injection pressure is 0.3MPa and the flow rate is 3 liter / min. The valves 5a and 5b are opened and rolling is performed from the spray nozzles 4a, 4b and 4c. The lubricant was sprayed at a spray pressure of 0.3 MPa. Next, the valves 5a and 5b are closed, the supply flow rate from the mixing device is adjusted according to the number of open valves, and the throttle hole 8 of the variable expansion device 6 is changed according to the state where the valves 5a and 5b are closed. When spray nozzle 4c
The concentration of rolling oil in the rolling lubricant sprayed from was investigated. The results are shown in FIG. 4 as an example of the invention.

On the other hand, as a comparative example, by using the rolling lubricant injection device shown in FIG. 3 having a throttle portion designed according to the opened state of the valves 5a and 5b, the valves 5a and 5b are opened and the spray nozzle 4a is opened. , 4b and 4c sprayed rolling lubricant of palm oil and dilution water. Next, the valves 5a and 5b were closed, the supply flow rate from the mixing device was adjusted according to the number of open valves, and the concentration of rolling oil in the rolling lubricant injected from the spray nozzle 4c was investigated. The result is shown in FIG. Since the other setting conditions are the same as those of the invention example, the description thereof will be omitted.

As is apparent from FIG. 4, the concentration of palm oil in the rolling lubricant was set at the initial set value (ie, in the invention example).
10% by mass) was maintained constant and in the comparative example, the palm oil concentration varied in the width direction of the nozzle header 1. This is because in the comparative example, the flow velocity in the injector portion did not rise and the flow rate of the rolling lubricant in the circulation flow channel 3 decreased, so that the rolling lubricant stayed in the circulation flow channel 3 and the incompatible palm was used. This is due to the separation of oil and dilution water.

As a comparison, a spray nozzle when the valves 5a and 5b are opened by using an injection device similar to that shown in FIG. 3 which has a throttle portion designed according to the case where the valves 5a and 5b are closed. However, due to the large pressure loss at the throttle, the injection flow rate from the spray nozzle could not be secured. In this way, according to the present invention, even if the number of spray nozzles for injecting the rolling lubricant changes, the flow rate of the rolling lubricant circulating in the circulation passage 3 is kept constant, and the concentration of the rolling oil is made uniform. It was confirmed that it can be maintained at.

[0030]

According to the present invention, the number of spray nozzles for injecting the rolling lubricant is adjusted according to the plate width of the metal plate to be rolled to reduce the consumption of rolling oil and to reduce the rolling lubricant. Even if the number of spray nozzles to be sprayed changes, the flow rate of the rolling lubricant circulating in the circulation passage is kept constant,
A rolling lubricant having a uniform concentration of rolling oil can be sprayed onto a metal plate or rolling roll.

[Brief description of drawings]

FIG. 1 is a sectional view schematically showing an example of a rolling lubricant injection device to which the present invention is applied.

FIG. 2 is a sectional view taken along the line AA in FIG.

FIG. 3 is a cross-sectional view schematically showing an example of a conventional rolling lubricant injection device.

FIG. 4 is a graph showing the distribution of the concentration of rolling lubricant.

[Explanation of symbols]

1 nozzle header 2 Nozzle header entry side piping 3 circulation channels 4a spray nozzle 4b spray nozzle 4c spray nozzle 5a valve 5b valve 6 Variable aperture device 7 rotation axis 8 aperture 9 Aperture member

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Koji Kawashima             1 Kawasaki-cho, Chuo-ku, Chiba-shi, Chiba Made in Kawasaki             Chiba Steel Works, Ltd. (72) Inventor Katsuhiko Kato             1 Kawasaki-cho, Chuo-ku, Chiba-shi, Chiba Made in Kawasaki             Chiba Steel Works, Ltd. F term (reference) 4D075 AA01 AA52 CA06 CA47 DA03                       DB01 EA06 EA37                 4F033 BA03 EA01 EA06 LA13 NA01

Claims (2)

[Claims] 1. A method for injecting a rolling lubricant through a plurality of spray nozzles arranged in the rotation axis direction of a rolling roll to inject a rolling lubricant according to the width of a metal plate used for rolling. By changing the number of the spray nozzle for injecting the rolling lubricant, and changing the opening area of the throttle hole provided in the nozzle header inlet side pipe in accordance with the number of the spray nozzles for injecting the rolling lubricant, A method for injecting a rolling lubricant, wherein a flow rate of the rolling lubricant circulating in a circulation passage provided in a nozzle header in which the spray nozzle is disposed is maintained constant. 2. A nozzle header having a plurality of spray nozzles in a rotating shaft direction of a rolling roll and having a circulation flow path through which a rolling lubricant circulates, and a flow path of the rolling lubricant injected from the spray nozzle. A variable throttle device for changing the opening area of the throttle hole provided in the nozzle header inlet side pipe according to the number of the spray nozzles for injecting the rolling lubricant. And a rolling lubricant injection device.