JP2003266116A - Method for supplying rolling oil in cold rolling mill - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of supplying rolling oil by which lubricity is improved and also emulsification dispersion stability is held even after the rolling oil is introduced into a circulation type rolling oil supplying tank. <P>SOLUTION: A 1st rolling oil supplying system for supplying emulsified rolling oil in a circulating manner in cold rolling and a 2nd rolling oil supplying system for supplying the emulsified rolling oil to the upper surface and the lower surface of a steel sheet are provided. This method is provided with: a stage where emulsion to which surfactant which is the same kind as the emulsion in the 1st rolling oil supplying system and has a lower concentration in oil than that of the 1st rolling oil supplying system is added and which is adjusted so as to have an average grain size larger than that of the emulsion in the 1st rolling oil supplying system is supplied from the second rolling oil supplying system to the upper and the lower surfaces of the steel sheet; and a stage in which the emulsion which is not stuck to the steel sheet is recovered, in which the surfactant is charged so as to be identical in the concentration in oil to that of the surfactant in the 1st rolling oil supplying system and the emulsion is joined with the emulsion in the 1st rolling oil supplying system after applying mechanical agitation. <P>COPYRIGHT: (C)2003,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cold rolling mill.
Rolling oil supply method.
The present invention relates to a method for supplying a rolling oil in a cold rolling mill to be used. [0002] In cold rolling, a steel sheet and a roll are rolled during rolling.
Lubricating oil is required to reduce friction between them. Ma
In addition, rolls are used to remove frictional heat and processing heat.
In addition, the steel plate needs to be cooled. Usually in cold rolling
Is lubricated using emulsion rolling oil. Emal
Is a state in which rolling oil particles are stably suspended in water.
Liquid mixture. Emulsions are characterized by concentration and particle size
Be charged. Emulsion concentration refers to the total emulsion
It is the ratio of the oil content volume to the volume. Particle size refers to emulsion
The diameter of the rolling oil particles in the oil. Also, the emulsion
To make, a surfactant is added. The amount of addition
Add a specified amount in the concentration relative to the amount of rolling oil (oil concentration)
And apply shearing by pumping and stirring.
Solution. Emulsion rolling in cold rolling
Oil supply method includes direct method (direct method), circulation
Method (recirculation method) and its compromise
There is a hybrid method. [0003] Direct rolling oil supply system (direct system)
Uses high-concentration emulsion rolling oil on steel sheets for lubrication
Spray and spray water on rolls for cooling
Excellent lubrication and cooling properties. However, unlike the circulation method,
Because the emulsion rolling oil is not circulated,
The basic unit of is high. On the other hand, a circulating rolling oil supply system (Recircu
The mixing method) is to mix rolling oil and cooling water in advance.
If the low concentration emulsion rolling oil created by stirring,
While circulating, the steel plate and rolls are slid for lubrication and cooling.
To play, the unit consumption of rolling oil is low. But directly
Lubricity and cooling performance are inferior to the rolling oil supply system
I cannot deny that. Therefore, the conventional circulation method
Is especially suitable for high-speed rolling of thin materials with a finished plate thickness of 0.2mm or less.
Rolling mill called chattering sometimes lacks lubrication
Vibration and surface flaws called heat scratches
Therefore, there is a problem that the rolling speed cannot be increased. On the other hand, lubrication by a circulating rolling oil supply system
As a conventional technique for improving the reliability, in Patent Document 1,
Rolling oil with a concentration of 10% or more is applied to the lower surface of the steel sheet immediately before biting.
A direct supply method is presented. In addition, low concentration and
Circulating rolling oil supply system to supply low temperature emulsion
Separately, high-concentration and high-temperature emulsions are supplied to steel sheets.
Hybrid method, which is a compromise method to improve lubrication
Has been presented. [0006] In Patent Document 2 and Patent Document 3, high density
Heat the emulsion to a high temperature (75 ° C), just before biting
Directly onto the steel sheet, and the high-concentration emulsion
Method by adding rolling oil to the extract from the lution
Is presented. [0007] In Patent Document 4, a high-concentration emulsion is added.
The added surfactant should be the same type as the circulating emulsion.
Emulsion stability index (ESI)
And a method of directly spraying the steel sheet. In Patent Document 5, salt formation is not performed.
Or use an ionic surfactant with a low salt formation rate
Sprayed directly on steel sheet as emulsion
Water-soluble counter-ionic substances in the circulation system tank.
Excessive addition of milk
A method for stabilization is proposed. [0009] However, the above prior arts include the following.
There was a problem. [0010] In the prior art presented in Patent Document 1,
Has a sufficient lubrication improvement effect for the following reasons:
Did not. A) contained in the emulsion to be sprayed
Plate out on the steel sheet surface
The ratio of the amount of oil adhering to the oil (hereinafter referred to as the adhesion efficiency)
Investigating the relationship between the emulsion concentration and
When the concentration is increased, the adhesion efficiency decreases, so only the concentration increases.
Did not provide sufficient plate-out. B) During high-speed rolling, only the lower side of the steel sheet is used.
Heat scratches may also occur on the top side.
You. In the high-speed rolling zone, not only the lower surface but also the upper surface
The amount of heat-out was also reduced, and the lubricity of only the lower surface of the steel plate was improved.
Good is not enough. [0013] Patent Documents 2 and 3
Some conventional technologies have sufficient lubricity improvement for the following reasons:
No effect. A) increasing the temperature of the emulsion;
If you check the effect on a real machine, make up the emulsion
Depending on the emulsifying dispersant, the temperature of the emulsion
The adhesion efficiency does not increase even if the
High temperatures are not effective. Also of the emulsion
As the concentration increases, the adhesion efficiency decreases, so the concentration increases.
Alone cannot efficiently increase the amount of plate-out. So
To compensate for the decrease in adhesion efficiency due to increased concentration.
Methods such as excessively increasing the supply flow rate.
There was a problem such as not. Also heat and add emulsion
Extra equipment such as a heater is required to press
On the other hand, high-temperature emulsions are
If mixed, the temperature of the emulsion in the circulating rolling oil supply system
The rolling oil supply system has a large
Extra equipment such as a cooler is required. B) Circulation of a hybrid emulsion
If it is attempted to obtain by extraction from the emulsion of the system,
Ring-based emulsions include ESI, iron content, saponification value, and acid value.
Which characteristics are not constant and how to obtain a stable extract
Requires complex equipment such as chemical treatment and iron removal filters
become. Also, once the characteristics of the extract change,
The characteristics and properties of hybrid emulsions
The lubricity has also changed, achieving the originally intended stable lubricity improvement.
I can't do it. In the prior art presented in Patent Document 4,
Introduces hybrid ES in the circulating oil supply tank
Unstable emulsion with low emulsifying dispersibility of low I
As a result, the ESI of the emulsion in the circulation system
And the emulsifying dispersibility becomes unstable,
Over-lubrication and slip occurs across all stands
There was a problem such as rolling and becoming unstable. In general, the circulating rolling oil supply tank has a capacity of 10
Although it has a large capacity of about 000 L, it is disclosed in Patent Document 5
In the prior art, there is a
It is necessary to add a large amount of a counter ionic substance,
Excessive ionic substances cause the
The dispersion stability of the emulsion.
You. The use of ionic surfactants with low salt formation
Salt formation reaction with the emulsion is less likely to occur, and as a result
The emulsion in the tank of the ring system becomes unstable
There was a problem. [Patent Document 1] Japanese Patent Publication No. 59-24888, (claim
[Patent Document 2] Japanese Patent Publication No. 58-5731 (Patent Document 2)
[Patent Document 3] Japanese Patent Application Laid-Open No. 9-122733,
[Patent Document 4] Japanese Patent Laid-Open No. 2-37911,
[Patent Document 5] JP-B-63-5167, (Claims)
[0023] The present invention relates to a recirculating rolling mill.
In the oil supply system, a circulating rolling oil supply system (first pressure
(Rolling oil supply system) and a second rolling oil supply system
The average particle size is larger than that of the circulating rolling oil supply system.
Supplying emulsion with high deposition efficiency to upper and lower surfaces of steel plate
To improve lubricity and supply circulating rolling oil
Retains emulsion dispersion stability of emulsion after mixing in tank
It is intended to provide a rolling oil supply method which can be performed. [0024] The present invention relates to a cold rolling method.
Rolling that supplies emulsion rolling oil in a circulating manner
Oil supply system and emulsion rolling oil
A second rolling oil supply system for supplying the second rolling oil
From the oil supply system, the first rolling oil supply system
Rolling oil supply system of the same type as the emulsion of
A surfactant having a lower oil concentration than the first,
Average particle size larger than the emulsion of the rolling oil supply system
Supplying the emulsion adjusted so that
The emulsion that did not adhere to the steel plate in the step of
Same as oil concentration of surfactant in the first rolling oil supply system
Surfactant was added to the mixture and mechanical stirring was added.
Later, it is merged with the emulsion of the first rolling oil supply system.
And the pressure in the cold rolling mill.
It is a method of supplying oil. Hereinafter, the principle of the present invention will be described. The inventors supply the emulsion to a steel sheet.
Intensively consider means to improve the adhesion efficiency
As a result, the emulsion concentration was adjusted
Increasing the average particle size of the material greatly improves the adhesion efficiency
I found that. FIG. 3 shows the amount of the surfactant added and the emulsion.
Shows the relationship of the average particle size. At this time, mechanical disruption
The emulsion was prepared with sufficient stirring and shearing. An example
For example, FIG. 3 (a) shows a cationic dispersion type surfactant.
When the concentration of surfactant to oil is 0.4% or more, the average
A stable emulsion having a particle size of 8 to 15 μm is obtained. Circulation pressure
The addition amount of the oil extension line is in this range. On the other hand, oil concentration
Emma with an average particle size of 20 μm or more with a degree of 0.005 to 0.2%
Rushon. FIG. 3 (b) shows the nonionic emulsion type
In the case of surfactants, the average grain size is 0.3% or more with respect to oil.
A stable emulsion having a diameter of 10 μm or less is obtained. Also oil
Emulsion with concentration of 0.003-0.2% and 20μm or more
It becomes. If the oil concentration is lower than 0.003%,
Small emulsion of less than 20μm by self-emulsification
Sometimes. FIG. 4 shows the results obtained by using a plate-out tester.
The relationship between the average particle size of the emulsion and the adhesion efficiency was investigated.
But the adhesion efficiency increases with increasing average particle size.
You. Especially, when the average particle size is more than 20μm,
Increase. FIG. 5 shows the emulsion concentration and the adhesion efficiency.
The adhesion efficiency decreases with increasing concentration.
You. However, the average particle size of the emulsion is 20 μm or more.
Decreasing adhesion efficiency with emulsion concentration as it gets larger
Is small. [0030] Particularly in the high-speed rolling zone, as the speed increases,
Shorter spray time, supply per unit area of steel plate
Since the amount of rolling oil is reduced, the
Even if the concentration and temperature of the solution are high, the condition is
There is no significant lubricity improvement effect, and the average particle size is large as in the present invention.
It is effective to use emulsion with high adhesion efficiency
It is. Also, during high-speed rolling, only the bottom
Heat scratches may also occur on the top side.
Therefore, it is necessary to improve the lubricity of the upper surface of the steel sheet.
Emulsi with high adhesion efficiency with large average particle size on the surface side
Needs to be supplied. The emulsion of the second rolling oil supply system is as follows:
Rolling oil stock solution, surface activity to obtain stable lubricity
Make a new formulation of the agent and dilution water. Emulsification dispersion
Surfactant added for the second rolling oil supply system
Was mixed into the circulating rolling oil supply tank
Same as the circulating rolling oil supply system to eliminate the effects of
Surfactants, and adjust the concentration of surfactant
To obtain an emulsion having a large average particle size. In the present invention, the same type as the circulating rolling oil supply system
Add a surfactant with a lower oil concentration and
Emulsions with larger average particle size than annular rolling oil supply system
Is supplied to the upper and lower surfaces of the steel plate on the side of the rolling stand.
This is based on the results of the above examination. From the second rolling oil supply system, the top and bottom of the steel sheet
Of the emulsion supplied to the surface does not adhere to the steel plate
Collected emulsion and put it into the circulating rolling oil supply tank.
In the flowing step, after the surfactant is added,
Add mechanical agitation to reduce the particle size to the same as the circulating emulsion.
Circulation by making a differentiated stable emulsion
Emulsion stability of the rolling oil supply system can be maintained
You. The additional amount of the surfactant at this time is based on the formula (6).
To decide. ## EQU1 ## Where qe (L / min) is the surface activity
The addition amount of the agent, q1 (L / min), is determined based on the second rolling oil supply.
The amount of the emulsion supplied to the system, f (%), is the value of the second rolling oil.
The adhesion efficiency of the emulsion in the supply system, q1 in the formula
・ (1-f / 100) does not adhere to the upper and lower surfaces of the steel plate.
It represents the amount of the emulsion. c (%) is the second rolling
Emulsion concentration of oil supply system, c0 (%)
The emulsion concentration of the rolling oil supply system, ce (%),
2, the oil concentration of the surfactant in the rolling oil supply system, ce0
(%) Is the concentration of surfactant in the circulating rolling oil supply system with respect to the oil concentration.
Indicates degree. Further addition of a surfactant and additional stirring
Agitate and shear to the same particle size as the circulating emulsion.
To obtain a stable emulsion finely divided by
Are as follows. (1) Surfactant in the circulation system tank
Re-addition and increase the rotation speed of the agitator in the circulation system tank
A method of adding strong stirring to the emulsion by increasing it. (2) Oil pan for recovering emulsion
To the emulsion storage tank in the circulating rolling oil supply system
In the middle of the return piping, add a surfactant
A method of installing an orifice or a stirring pump. (3) Oil pan for recovering emulsion
Surfactant is added in the inside and circulation rolling from oil pan
Return piping to the oil storage tank in the oil supply system
A method of installing an orifice inside or installing a stirring pump. (4) Emulsion of circulating rolling oil supply system
Buffer tank for recovery separately from the storage tank
A surfactant in the emulsion recovered in the
Addition, stirring and shearing with an agitator
Law. FIG. 6 shows a plate-out tester.
Different surfactants a, b and c are emulsified and dispersant
For emulsions created as
It is the result of investigating the relationship between the degree and the adhesion efficiency. By this
And raising the emulsion temperature is due to the surfactant c
The amount of plate-out decreases depending on the emulsifying dispersant
In some cases. Play like surfactants a and b
May increase, but the increase in adhesion efficiency is small.
The heater and other equipment to keep the emulsion at a high temperature
To keep the emulsion at a high temperature,
It is not a good idea to do so. Also mixed with the circulating rolling oil supply system
Emulsion temperature of the circulating oil supply system
Circulating rolling oil supply system
Requires a cooler. Therefore, in the present invention, the second pressure
The emulsions of the rolling oil supply system and the circulating rolling oil supply system
Same temperature. The concentration of the emulsion in the second rolling oil supply system
The flow rate and flow rate will vary depending on the conditions and plate
Determined in consideration of the out characteristics. First, a given plate
It is a necessary condition to secure the out amount. This necessary
Set the plate-out amount to Pφmin (unit: mg / m ^Two )When
I do. Pφmin is heat scratch flaw and chattering
Is the minimum amount that does not occur. Below, plate out
The amount is expressed by the symbol PΦ (unit: mg / m ^Two ). Article 1
The matter is represented by equation (1). Pφmin ≦ PΦ Equation (1) Second, the plate-out amount is constant as shown in FIG.
Above the emulsion feed rate, the saturation occurs and the adhesion efficiency decreases.
I do. For this reason, the amount of emulsion supplied
It is desirable to set it within a range where the amount does not saturate. this
The supply amount at the saturation limit is defined as ωτmax (unit: L /
m ^Two ). However, ωτ is the amount of emulsion supplied (simple
Position is L / m ^Two ), And ω is the flow density (unit is L /
m ^Two ) And τ represent spray residence time (unit is min)
You. According to FIG. 7, ωτmax is about 0.1 L / m ^Two so
is there. Q (L / mi)
n), the width of the spray portion is w (m), and the rolling speed is V (m /
min) and the amount of emulsion supplied is ωτ (L / m ^Two )
Then, it can be calculated by Q = (ωτ) · w · V. w = 1.2
m, V = 1800 m / min, ωτ = 0.1 L / m ^Two of
Then, Q = 215 L / min. From this, 1
The flow rate per header is 215 L / min at maximum.
You. The second condition is represented by equation (2). Ωτ ≦ ωτmax Equation (2) Further, the plate-out amount is calculated with respect to the emulsion supply amount.
In the non-saturated region, the plate-out amount is calculated by equation (3).
Can be calculated. Here, PΦ is the plate-out amount (unit is m
g / m ^Two ), C is emulsion concentration (%), f is adhesion
The efficiency (%) and K are unit conversion coefficients (mg / L). K
0.89 × 10 ⁶ ~ 0.9 ×
10 ⁶ It is about. PΦ = K · c / 100 · ωτ · f / 100 Equation (3) Third, the adhesion efficiency f is, as shown in FIG.
Concentration as low as possible
And In addition, as shown in FIG.
Affected by the particle size. Adhesion efficiency f (%)
The relationship between the concentration c (%) and the oil average particle diameter d (μm) is expressed by the following equation.
Represented by (4). Here, f represents a function. F = f (c, d) Equation (4) When Equations (1), (3) and (4) are rearranged, Equation (4) is obtained.
The condition of (5) is obtained. C · f (c, d) ≧ Pφmin / ωτ · K Formula (5) From the above, the concentration of the emulsion in the second oiled oil supply system is obtained.
The degree and the average particle size must satisfy the expression (5). For example, an emulsion showing the adhesion efficiency shown in FIG.
In the case of an average particle size of 20 μm,
A calculation example is shown below. PΦmin in the equation (5) is calculated according to the following procedure.
Ask. First, heat scratch flaws and chatarin
The relationship between the occurrence of rolling and the amount of oil adhering to the steel sheet on the rolled material.
The lower limit of the amount of oil adhering to a steel sheet when no oil
(Unit is mg / m ^Two ). At this time,
Plate out amount Pφmin on steel plate surface (unit is mg /
m ^Two ) Is with the rolled steel plate on the roll surface at the exit of the rolling mill
Assuming that the same amount of rolling oil as the amount of oil has adhered, P
φmin = 2.0 min / (1-r.
And r represents the rolling reduction during rolling. For example, 0 min is 3
00mg / m ^Two When the rolling reduction r is 0.3, Pφmin
Is 860 mg / m ^Two It becomes. Emulsion supply amount ωτ
Assuming that ωτmax is 50%, the average particle diameter 20 shown in FIG.
Use the relationship between emulsion concentration and adhesion efficiency at μm
The minimum concentration of the emulsion satisfying the formula (5) is determined.
Then, it becomes 6.2%. On the other hand, the emulsion of the above-mentioned example was
When used as an emulsion in a rolling oil supply system,
Apply sufficient shear to reduce average particle size to less than 20μm
To obtain an emulsion that is emulsion-stable and has a concentration of 1.0 to 5.
Used as about 0%. As can be seen from this example, the above equation
Considering the conditions (1) to (5), the second rolling oil supply
The emulsion concentration in the feed system is
Higher. The injection pressure of the rolling oil is 0.5 kg
/ Cm ^Two ~ 7kg / cm ^Two Is preferred. 0.5kg / c
m ^Two Is the emer sprayed from the header for the bottom of the steel plate.
This is the minimum pressure at which the solution can reach the steel sheet surface. Ma
7kg / cm ^Two When this happens, it will collide with the steel plate surface
The amount of the scattered emulsion increases, and the adhesion efficiency decreases.
You. Therefore, 0.5-7 kg / cm ^Two Set about
Is preferred. Rolling oil supply according to the first invention described above
By using the system, the conventional circulating rolling oil supply system
The lubricating property can be greatly improved as compared with the above. FIG. 8 shows circulation rolling.
Steel sheet adhesion of rolled material in oil supply system and second rolling oil supply system
It is a comparison result of an oil amount. In addition, the measurement of the amount of oil adhering to the steel sheet
Extract the oil on the steel sheet surface with an organic solvent such as hexane and extract
Performed by measuring the oil output (solvent extraction method)
Was. At this time, the concentration of the emulsion of the circulation rolling oil supply system was
Degree is 3.5%, average particle size is 10μm, top and bottom header
-The emulsion supply rate is 4000 L / min
You. On the other hand, the concentration of the emulsion in the second rolling oil supply system
Is 10%, average particle size is 20μm,
The emulsion supply rate was 130 L / min. Book
When using the first invention, the amount of steel sheet adhesion is
It is about 40% higher than the oil supply system.
In terms of the deposition efficiency, which is indicated by the ratio of the amount of deposited oil to
Approximately 12 times the effect was observed. Also, in the present invention, the second rolling oil supply
Spray nozzle for supplying system emulsion
Can be located on the upstream stand away from the roll bite
It is preferable that the position be as close as possible. This is for the following reasons
by. To form a stable plate-out layer
Is an O / W emulsion in which oil is dispersed in water
W / O emulsion in which water is dispersed in oil or oil
Check the time for phase inversion (hereinafter referred to as phase inversion time).
It is preferable to maintain. In the rolling mill,
After the emulsion is supplied to the steel sheet surface,
The time required to reach the roll bite depends on the phase inversion time
Equivalent to. Therefore, as the rolling speed increases, the phase inversion time
Becomes shorter, making it difficult to form a plate-out layer
It is assumed that In contrast, the position of the spray nozzle
As close as possible to the upstream stand away from the roll bite
The phase change time can be secured by setting the position to a suitable position. The second invention is based on the following examination results.
It is. In the circulating rolling oil supply system, the strip
Rolled oil and pressure are removed to remove the oil that has adhered to the system.
Lost due to evaporation, leaks and scum out in the mill
Replenish the rolling oil and water
Volume and emulsion concentration at a certain level.
You. On the other hand, the second rolling oil supply system
The emulsion recovered after spraying is
Concentration higher than emulsion, concentration of oil surfactant
And the average particle size should be the same as the circulating emulsion
Recirculating rolling oil supply system due to additional surfactant
Can be used as a replenisher oil. The second invention is made based on such a viewpoint.
It is a thing. That is, the second invention provides a second rolling oil
Mix from the supply system into the tank of the circulating rolling oil supply system
Oil exceeds the oil loss of the circulating oil supply system.
If the concentration in the circulating oil supply system tank is
Replenish only with dilution water to make constant. At this time, the tank
Emulsion liquid volume increases while maintaining a certain concentration
This means that oil loss has been replenished in advance.
Value. The circulation pressure is supplied from the second rolling oil supply system.
The amount of oil mixed into the tank of the oil supply system is
Exceeds the oil loss of the oil supply system and
If the emulsion volume exceeds a certain level,
No new oil replenishment is required and the concentration is kept constant.
Replenish with dilution water only. Further, the second rolling oil supply system is connected to the circulation system.
The amount of oil mixed into the tank is controlled by the circulation rolling oil supply system.
Less than the oil loss and the emulsion in the tank
If the fluid volume is maintained at a certain level or is low
Is a surfactant in the emulsion of the second rolling oil supply system
Oil concentration is the same as that of the emulsion in the circulating oil supply system.
The emulsion adjusted to be the same
Replenish to the supply tank and replenish dilution water. Emma of dilution water and second rolling oil supply system
The replenishment amount of the circulating pressure is calculated as shown in equation (7).
Emulsion of the second rolling oil supply system mixed into the oil rolling system
Oil loss of the circulating rolling oil supply system from the oil content of the
(8) to (11) according to the oil amount ΔQo obtained by subtracting
Is determined based on In addition, the second rolling oil supply system
The additional amount of the surfactant to the emulsion is expressed by the formula (12).
Decide based on ## EQU2 ## ## EQU3 ## [Mathematical formula-see original document] [Mathematical formula-see original document] (Equation 6) [Mathematical formula-see original document] Here, ΔQo (L / min) is calculated by
Oil content increase in rolling oil supply system, ΔQw (L / min)
Is the water increase in the circulating rolling oil supply system, QLo (L /
min) is the oil loss of the circulating rolling oil supply system, QL
w (L / min) is the water loss of the circulating rolling oil supply system
Volume, ΔQE (L) is the amount of emulsion liquid in the tank.
The deviation from the standard level, W (L / min), is
The feed rate, q2 (L / min), is the value of the second rolling oil supply system.
The amount of replenishment from the tank to the tank of the circulating oil supply system,
q1 (L / min) is a steel sheet from the second rolling oil supply system.
The amount of emulsion supplied to qe (L / min)
The addition amount of the activator, c (%), is determined according to the value of the second rolling oil supply system.
The concentration, c0 (%), is the concentration of the circulating rolling oil supply system, c
e (%) is the ratio of surfactant to oil in the second rolling oil supply system.
The concentration, ce0 (%), is the surface activity of the circulating rolling oil supply system.
The oil concentration, f (%), of the surfactant is determined by the second rolling oil supply system.
The adhesion efficiency of the emulsion. The circulation oil is supplied from the tank of the second rolling oil supply system.
To the emulsion to be replenished to the tank of the annular rolling oil supply system
Additional surfactant added for additional agitation and shear
Stable emulsions with the same average particle size as emulsions in more circulating systems
Methods for obtaining a emulsion include the following. (1) Emulsion of Second Rolling Oil Supply System
After refilling into the tank of the circulating oil supply system
Additional surfactant is added, and the number of rotations of the agitator in the tank
Increase the emulsion by vigorously stirring and shearing
How to add. (2) From the tank of the second rolling oil supply system
In the middle of the feed piping to the tank of the circulating oil supply system,
After the surfactant is added, pass through the feed pump.
And a method of applying shear to the emulsion. (3) What is the tank of the second rolling oil supply system?
Separately, a buffer tank for adjusting the amount of surfactant
And add a surfactant in it and add agitator
A method of stirring and shearing the emulsion. (4) What is the tank of the second rolling oil supply system?
Separately, the same pair as the emulsion of the circulation type rolling oil supply system
Storage of replenishment emulsion with oil concentration of surfactant
A method of providing a storage tank. By using the replenishment method described above,
The emulsion of the second rolling oil supply system is
Since the replenishment of insufficient oil in the supply system is also used effectively,
As in the case of the conventional circulating oil supply system,
Intensity can be reduced. According to the second aspect of the present invention, the second rolling oil
The supply system is to be rolled using only the circulating oil supply system.
Oil loss in the circulating oil supply system
Applicable as a method. Emul of the second rolling oil supply system
The replenishment amount and dilution water are ΔQo = -QLo, ΔQ
w = −QLw, and is determined based on the equation (11). [Embodiment 1 of the Present Invention] FIG.
This is an example of the embodiment of the first invention, and has a total of five stands.
This is a case where the present invention is applied to the fourth and fifth stands of Ndem Mill.
Applied to the 4th and 5th stands,
Since the rolling speed is high and the plate thickness is thin, the rolling load
And lubrication conditions become severe. Figure
In No. 1, No. In 1-3 stands, conventional circulation
Lubrication and cooling were performed by a rolling oil supply system.
In the 4th and 5th stands, lubrication is performed according to the first invention.
The cooling oil is supplied by the rolling oil supply system 2
The rolling oil supply system performed by the supply system is shown. In addition, circulation
The rolling oil supply system of No. For 1-3 stands, and
No. It is divided into two systems for 4-5 stands. In FIG. 1, reference numeral 1 denotes an emboss of the second rolling oil supply system.
It is a storage tank for Luchon. Hot water, crude oil, surfactant
Supply pumps 5a, 5b, 5 from the tanks 2, 3, 4
c, a predetermined oil concentration, a surfactant-to-oil concentration and
Adjust the replenishment amount with the flow control valves 6a, 6b, 6c so that
And supplied to the emulsion storage tank 1. tank
The emulsion concentration within the range is 4 to 15%.
The type of surfactant is the same as that of the circulating rolling oil supply system.
The oil concentration is lower than that of the circulation rolling oil supply system. example
For example, in the case of a cationic dispersion type surfactant, circulation rolling
While the oil concentration in the oil supply system is 0.5%, the second
The oil concentration of the rolling oil supply system of
Range. Then, mechanical stirring is performed by the agitator 7.
Enough to make the average particle size in the tank 20-40 μm.
adjust. The emulsion temperature is controlled by the circulation rolling oil supply.
The same temperature as the supply system. Emulsion of this second rolling oil supply system
The liquid passes through a rolling oil supply line 9a by a pump 8a.
From header 10a and header 10b
It is supplied to the upper and lower surfaces of the top. Flow rate per header
215 L / min maximum, size of rolled material and steel
Adjust according to species. After spraying on the steel plate, plate
Emulsion that does not go out is collected in the recovery oil pan 17b.
Collected along with the emulsion in the circulation circuit for cooling.
To the stirring section 27 via the return line 30b.
It is thrown. In the stirring section, determined by equation (6)
The amount of surfactant to be added is adjusted by adjusting the opening of the valve 29 and added.
After adding additional agitation by the gitator 18, the pump 28
Into the circulating rolling oil supply tank 13b
You. For example, the emulsion of the circulating rolling oil supply system,
The concentration was 2.5% and the concentration of surfactant to oil was 0.5%.
Emulsion of rolling oil supply system of 2
0.1% oil concentration of surfactant,
20 L / min for # 4 STD, 30 for # 5 STD
When L / min, the surface activity to the stirring section 27
The additional amount of the activating agent is 8.4 cc / min. FIG. 9 shows a second rolling oil supply according to the first invention.
Emma in the circulation system tank 13b when using the supply system
This is the result of investigating the particle size distribution of lution. Comparison
And the emulsion in the tank 1 of the second rolling oil supply system
Particle size distribution and when the second rolling oil supply system is not used
Particle Size Distribution of Emulsion in the Circulation System Tank 13b
Also shown. Circulation using the second rolling oil supply system
The emulsion in the ring system tank 13b is the second rolling oil
Emulsion particle size distribution without supply system and
According to the first invention, the circulation rolling oil supply
It can be seen that the emulsifying dispersibility of the system can be maintained. The recovered second rolling oil supply system
Add a surfactant to the emulsion, add additional stirring and
And shearing, using the method shown below
Is also good. (1) After merging into the circulation system tank,
Additional surfactant is added to the ring system tank and the agitator
Add strong stirring to the emulsion by increasing the number of revolutions
Method. (2) As shown in FIG.
In the middle of the return pipe 30b from the nozzle 17b,
Addition from tank 4 via piping 32 and valve 33
And the emulsion was stirred by a stirring pump 34 installed in the middle of the pipe.
After shearing the oil, the tank of the circulating oil supply system
13b. (3) As shown in FIG.
In the tank 17b, a surfactant is supplied from the tank 4 to the pipe 3
5. Add via the valve 36 and add the oil pan 17b
A stirring port installed in the middle of the return pipe 30b from the tank to the tank
After shearing the emulsion with a pump 34, the
A method of joining the rolling oil supply system with the tank 13b. On the other hand, the emulsification of the circulating rolling oil supply system
No. 1 solution No. 1-3 stand tank 13a, No.
The stirrer 18 is stored in the tank 13b for the 4,5 stand.
To give a stable emulsion with a small radius.
You. Emulsion particle size is cationic dispersion type surfactant
When the oil concentration is 0.5%, the average particle diameter is 8 to
15 μm, but other emulsifying surfactants
When used, the average particle size may be 10 μm or less.
You. The emulsion concentration is usually in the range of 1-4%.
You. If tallow is used as the base oil, the emulsion temperature should be 5
5 to 70 ° C. Other synthetic ester-based rolling oils
In some cases, it may be lower. This circulatory system
Are the emulsions of stirring tanks 13a and 13b
From the rolling oil supply line 15 by the pumps 14a and 14b.
a, 15b. N for lubrication by circulation system
o. For the first to third stands, headers 19a, 19
b. Supply emulsion to roll bite
You. The flow rate is 1000-2000 for each header
L / min. No. 1-5 stands
At the outlet side of the cooling emulsion supply system 20,
Trip 21, work roll 22, backup roll
Spray to 23 and cool strips and rolls
Reject. The flow rate is 1000-2 for each header.
000 L / min. After that, the circulation system
The emulsion is turned by the recovered oil pans 17a and 17b.
Circulated through return lines 30a, 30b
Tanks 13a and 13b. FIG. 22 shows an embodiment as shown in FIG.
Supplies the emulsion of the second rolling oil supply system at
Location of the header to be
This is an embodiment in which the position is as close as possible to the command. this
O / W emulsion to W / O emulsion
In other words, the time for inverting the oil to a single phase is secured.
The position of the header is determined by the roll and
Affected by coolant header 20 for cooling
Immediately after (1.0 m from the exit side of the front stand). In addition,
The distance between the stands is 4.5 m. [Second Embodiment of the First Invention] FIG.
(2) A tandem mill having 5 stands in total according to an embodiment of the present invention.
This is the configuration of the device when applied to. In addition, the second rolling oil
The device configuration of the supply system is the same as that shown in FIG.
The same is true. Circulation from tank 1 of second rolling oil supply system
Emulsion to replenish system tanks 13a and 13b
From the pump 8b via the supply pipe 9b,
It is put into an oil pan 31 for adjusting the amount of the agent. This
Here, the opening of the valve 6d is adjusted, and is determined by the equation (12).
After a predetermined amount of surfactant is added, the feed pump 1
After applying shearing at 6, the circulation system tanks 13a, 13
b. The replenishment amount is determined by the valves 26a,
It is adjusted by the opening degree. Note that circulation from the second rolling oil supply system tank
Of the emulsion to be replenished to the tanks 13a and 13b of the system
Same concentration of surfactant to oil as circulating emulsion
And add additional stirring and shearing
The following method may be used. (1) Emulsion of second rolling oil supply system
Was refilled into the circulation system tanks 13a and 13b.
Later, a surfactant is added and the air in the circulation system tank is removed.
Emulsion is strongly disrupted by increasing the rotation speed of the gitator.
A method of adding stirring. (2) As shown in FIG. 12, the second rolling oil
Feeding from tank 1 in the supply system to tank 13b in the circulation system
In the middle of the pipe 38, a surfactant is supplied to the valve 39 and the pipe 40.
And then passed through the supply pump 41
By applying shear to the emulsion. (3) As shown in FIG.
A replenishing tank 42 is provided, and the emulsion concentration is
Rolling oil supply system of
The hot water tank 2, crude oil tank
(3) Piping 43a, 43b, 4 from the surfactant tank 4
Refill with valves 44a, 44b, 44c via 3c
Adjust the amount and place it in the agitator 45 in the refill tank 42.
The particles are finely divided by vigorous agitation by
Create a stable emulsion in the same way as
Pump 46 to the circulation system tank via pipe 47
How to pay. In the calculation device 24b, the tank 13b is refilled.
Emulsion and dilution water of the second rolling oil supply system
Replenishment amount and surface activity added to oil pan 48
Calculate dosage. FIG. 14 shows the calculation flow.
No. from the second rolling oil supply system by the 4,5s
Measures the supply amount q1 sprayed on the steel plate surface on the entry side of the stand
Based on this, the emulsion of the second rolling oil supply system
Replenishment amount q2, amount of surfactant added to oil pan 48
qe and the dilution water amount W are calculated according to equations (7) to (12).
calculate. Based on this, the flow control valves 6d, 31, 1
2b and 26b are controlled. For example, No. Circulation system for 4,5 stands
Emulsion concentration of 3.5%, surfactant to oil concentration
0.5%, oil loss amount and water loss amount are each 1.
4L / min, 18.4L / min, second rolling oil supply
10% emulsion concentration in tank 1 of the system, surfactant
When the concentration of the agent in the oil is 0.1%, the supply amount to the steel sheet is N
o. 20L / min, 30L / m at 4 and 5 stands respectively
When "in" is used, the increase in oil content of the circulating rolling oil supply system
From equation (7), ΔQo = 2.1 L / min and ΔQo>
It becomes 0. Reduce the emulsion concentration in the circulating oil supply system
Replenish only with dilution water to keep constant. Its replenishment
The quantity W is 55.3 L / min from the equation (9). Further, the supply amount to the steel sheet was 4,5 star
Circulating rolling oil supply at 5 L / min
From equation (7), the oil increase in the system is ΔQo = −0.14
L / min and ΔQo <0, and the circulating rolling oil supply system
It is necessary to replenish the rolling oil. At this time, the circulation system
The amount of emulsion in the ink tank is maintained at a certain level.
(ΔQ _E = 0) is the second rolling oil supply system
Replenish the emulsion and dilution water. From equation (11)
The feed rate q2 of the emulsion is 1.4 L / min, and the dilution water
The replenishment amount W is 6.4 L / min, and is calculated by the equation (12).
The additional amount of the surfactant was 0.6 cc / min.
You. Further, the amount of the emulsion liquid in the tank is constant.
(ΔQ _E > 0), supplement only with dilution water
Pay. From the formula (10), the replenishment amount W is 33.0 L
/ Min. In the calculating device 24a, the first
Emulsion from tank 1 of rolling oil supply system 2
And the replenishment volume of the dilution water is calculated. Emul from tank 1
And the replenishment amount W of the dilution water are expressed by the formula (1).
1) Calculate the additional amount qe of the surfactant from equation (12).
Then, based on this, the flow control valves 6d, 31, 12a,
26a is controlled and the oil content of the circulating rolling oil tank 13a is controlled.
The charge is made. For example, No. Circulation system for 1-3 stands
Emulsion concentration of 2.5%, surfactant to oil concentration
Degree is 0.5%, oil loss amount and water loss amount are each 0.
6 L / min, 7.9 L / min, and second rolling
10% emulsion concentration in tank 1 of oil supply system
When the surfactant has an oil concentration of 0.1%, the replenishment amount W of the dilution water
Is 25.9 L / min and the air from the second rolling oil supply system is
The emulsion feeding amount q2 is 6 L / min. Also, the world
The additional amount of the surfactant is 13 cc / min. [Example 1] Tandem rolling mill with 5 stands in total
The first invention (first embodiment) is applied to the fourth and fifth stands.
And lubrication of the fourth and fifth stands to the second rolling oil supply system
Was performed. The base oil of rolling oil is tallow (viscosity of 40 ° C 45
cSt) and a cationic surfactant as an emulsifying dispersant
Was used. Cooling the emulsion in the second rolling oil supply system
The runt temperature should be 60 ° C, the same as for the circulating rolling oil supply system.
Was. Also, the emulsion concentration of the second rolling oil supply system is
The emulsion particle size was 10%, and the surfactant was
Degree is lower than emulsion of circulation rolling oil supply system
The average particle size was adjusted to 20 μm as 0.1%. Also,
The amount of emulsion supplied from the second rolling oil supply system
100L / min at stand, 130L / at 5th stand
min. Lubrication of other stands and all stands
The cooling of the metal was carried out using a circulating rolling oil supply system as before.
3.5% emulsion concentration in the circulating rolling oil supply system,
The surfactant has an oil concentration of 0.6% and an average particle size of 10 μm.
And As a comparison of the first invention, the fourth and fifth inventions were compared.
Lubricate the stand as before using the circulating rolling oil supply system
In the case where the amount of the emulsion supplied is 2500 at the fourth stand,
L / min, 4000L / min at the 5th stand
Was. By supplying the rolling oil as described above,
Rolling while changing, chattering occurrence and heat
The occurrence of scratches was investigated. Target materials are finished
2 of hard and soft tin materials having a thickness of 0.2 t or less
Type. The results of each survey are shown in Tables 1 and 2 below.
You. (1) The steel type of the target material 1 is a hard tin plate
The dimensions are 1.8 mm in base material and 0.3 mm in finished thickness.
It is 18 mm in width and 900 mm in width. As shown in Table 1, the first invention is used.
No chattering or heat scratches
It was able to accelerate to 2100 mpm. On the other hand, in the conventional method, 1
Chattering occurs at 500 mpm and further acceleration
Was impossible. FIGS. 15 and 16 show the rolling speed and pressure, respectively.
The amount of oil adhering to the steel sheet of the rolled material, the rolling speed and the
The relationship between the coefficient of friction was compared between the method according to the first invention and the conventional method.
Shown in comparison. The amount of oil adhering to the steel sheet is determined by the solvent extraction method.
It is the average of the values obtained for the upper and lower surfaces. In the conventional method, a high-speed range of 800 mpm or more
The amount of oil adhering to the steel sheet decreased significantly in
In the invention, a stable amount of oil adhering to the steel sheet was obtained even in the high-speed range.
Have been. Also, in response to this, the friction
The increase in the number is suppressed, and a stable friction coefficient is obtained even at high speeds.
It can be seen that the lack of lubrication has been eliminated. As shown in the test results, the target material 1 was rolled.
When the lubrication of the 5th stand is performed by the circulating rolling as before
With the oil supply method, chattering due to insufficient lubrication
, The rolling speed is limited to 1500 mpm,
High-speed rolling was hindered. In contrast, the first invention
By using it, the lack of lubrication in the high-speed range can be eliminated.
Therefore, occurrence of chattering can be prevented beforehand, and 210
High speed rolling of 0 mpm becomes possible. FIG.
When the circulating rolling oil supply system and the first invention are used
Shows the distribution of the average speed when the target material 1 is rolled.
However, according to the first invention, the average speed is 1350 m
pm to 1700 mpm. [Table 1] (2) The steel type of the target material 2 is a soft tin plate
The dimensions are: base material thickness 2.3 mm, finish thickness 0.
20 mm and a board width of 1000 mm. The target material 2 is softer than the target material 1.
However, in the conventional method, the fifth stand
The frequency of occurrence of heat scratch flaws was high. As shown in Table 2, the first invention is used.
Up to 2100 mpm without heat scratch flaws
I was able to accelerate. On the other hand, in the case of the conventional method, 1700 mpm
Causes slight heat scratches and higher speed
In the region, remarkable heat scratch flaws occurred. FIGS. 18 and 19 show the rolling speed and the pressure, respectively.
The amount of oil adhering to the steel sheet of the rolled material, the rolling speed and the
The relationship between the coefficient of friction was compared between the method according to the first invention and the conventional method.
Shown in comparison. In the conventional method, the amount of steel
In contrast to the large decrease, the first invention
In this case, a stable amount of oil adhering to the steel sheet was obtained. Also,
Correspondingly, the increase in the coefficient of friction of the fifth stand is suppressed.
And a stable friction coefficient even at high speeds.
It can be seen that the shortage has been resolved. FIG. 20 shows the rolling speed and the output of the fifth stand.
The relation of the steel plate temperature is shown. In the conventional method, the temperature
Temperature rise is large and exceeds 170 ° C at 1700 mpm or more
In addition, heat scratch flaws occurred. On the other hand, the first invention
According to the above, the temperature rise is suppressed and heat scratch flaws are generated.
Life is gone. The reason is that according to the first invention,
Since the increase in the coefficient of friction in the high-speed rolling zone can be suppressed,
Heat generation is reduced, and as a result, the temperature of the steel sheet at the exit side of the fifth stand
Is to be reduced. As shown in the test results, the target material 2 was rolled.
In the case of lubrication, the lubrication of the 4th and 5th stand
When using the rolling oil supply method, heat scratch flaws occur
The rolling speed is limited to 1700 mpm due to
Nobu was impeded. However, using the first invention
This eliminates the lack of lubrication at high speeds,
Auto scratches can be prevented from occurring and high as 2100 mpm
Speed rolling becomes possible. FIG. 21 shows a conventional circulation rolling method.
Rolling the target material 2 when using the oil supply system and the first invention
This shows the distribution of average speed when
By using light, average speed from 1550 mpm
Improved to 1900 mpm. [Table 2] [Example 2] Tandem rolling of all 5 stands
The first invention is applied to the fourth and fifth stands of the
When lubricating the stand with the second rolling oil supply system,
Replenish oil loss and water in the circulating rolling oil supply system
This was performed according to the second invention (Embodiment 2). Rolling oil base
Oil as beef tallow (viscosity of 40 cSt 45 cSt), emulsifying dispersant
A cationic surfactant was used. According to the first invention
The concentration of the emulsion in the second rolling oil supply system to 10
%, The oil concentration of the surfactant,
0.1% lower than the emulsion and the average particle size is 20%
It was adjusted to μm. In addition, Emulsion
Concentration of 3%, surfactant to oil concentration of 0.6
%, And the average particle size was 9 μm. The temperature of the emulsion
The degree was the same at all, and was set to 60 ° C. Table 3 shows that the target rolled material was a base material having a thickness of 1.8 to
2.0mm, Finish thickness 0.16-0.20mm, Sheet width 8
The pressure when a thin tin plate of 00 to 1200 mm is used
Comparison of the method of the present invention with the conventional method
Shown. At this time, from the second rolling oil supply system
The emulsion feed rate is adjusted according to the finish thickness,
When the thickness is 0.16 to 0.20 mm, the fourth stand and
The supply amount of the fifth stand is 100 L / min, 13
0 L / min, when the finish thickness is 0.20 to 0.25 mm
In this case, they were 5 L / min and 15 L / min, respectively. on the other hand,
Emulsion sprayed as conventional lubrication
The supply amount was 3000 L / min at the fourth stand, and
It was 4000 L / min with a stand. According to the second invention, the rolling oil consumption rate is
System (circulation system). this
According to the first invention, the emulsification of the second rolling oil supply system
Oil as a replenisher for oil loss in the circulating rolling oil supply system.
The effect that can be used effectively and the amount of emulsion supplied
Oil from fumes
This is due to the effect that the loss amount can be reduced as compared with the conventional method. [Table 3] As described above, according to the first aspect of the present invention,
Emulsion with an average particle size of 20μm
To the upper and lower surfaces of the steel plate on the side of the rolling stand.
This allows the steel sheet to adhere to the upper and lower surfaces even in the high-speed rolling zone.
The amount of oil can be greatly improved. This gives a finished plate thickness of 0.2
mm when rolling thin materials
The lack of lubrication that had occurred at the time of delay was resolved, and chattering
Further, generation of heat scratch flaws can be prevented beforehand.
Along with this, the rolling speed can be increased, resulting in a significant increase in productivity.
Can be improved. Further, according to the first invention, the circulation pressure
Emulsion dispersion stability of emulsion in oil supply system secured
As a result, stable operation is possible. According to the second aspect of the present invention, the second rolling oil
The emulsion in the supply system is a supplement to the circulating oil supply system.
It can also be used as refueling, and the basic unit of rolling oil is the conventional circulation type
It becomes possible to make it lower than the rolling oil supply system.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view showing an example of application to a tandem rolling mill according to a first embodiment of the first invention. FIG. 2 is a diagram showing an example of application to a tandem rolling mill according to a second embodiment of the first invention. FIG. 3 is a graph showing the relationship between the oil concentration of a surfactant and the average particle size of an emulsion. FIG. 3 (a) shows the case where the surfactant is a cationic dispersant and the rolling oil is tallow, and FIG. The case where the surfactant is a nonionic emulsifier and the rolling oil is a synthetic ester rolling oil is shown. FIG. 4 is a graph showing the relationship between the average particle size of the emulsion and the adhesion efficiency. FIG. 5 is a graph showing the relationship between the concentration of an emulsion and the adhesion efficiency. FIG. 6 is a diagram showing the relationship between the temperature of the emulsion and the adhesion efficiency. FIG. 7 is a diagram showing a relationship between an emulsion supply amount ωτ and a plate-out amount. FIG. 8 is a comparison diagram of a steel sheet adhesion amount of a rolled material in a circulating rolling oil supply system and a second rolling oil supply system. FIG. 9 is a diagram showing a comparison of the emulsion particle size distribution of the circulating rolling oil supply system when the second rolling oil supply system is used and when it is not used. FIG. 10 is a diagram showing an example of a method of replenishing the amount of surfactant to the circulation system tank and additionally stirring. FIG. 11 is a diagram showing another example of a method of replenishing the amount of surfactant to the circulation system tank and additionally stirring. FIG. 12 is a diagram showing an example of a method of replenishing a circulation system tank from a second rolling oil supply system. FIG. 13 is a view showing another example of a method of replenishing a circulation system tank from a second rolling oil supply system. FIG. 14 is a diagram showing a calculation flow in a calculation device. FIG. 15 is a diagram showing a comparison (target material 1) of the amount of oil adhering to a steel sheet between the rolled material of the first invention and the conventional method. FIG. 16 is a diagram showing a comparison of the coefficient of friction between the first invention and the fifth stand of the conventional system (target material 1). FIG. 17: Comparison of rolling speed distribution between the first invention and the conventional method
The figure which shows (target material 1). FIG. 18 is a diagram showing a comparison of the amount of oil adhering to a steel sheet between the first invention and the conventional method (rolled material 2). FIG. 19 is a diagram showing a comparison (friction material 2) of the friction coefficient between the first invention and the fifth stand of the conventional system. FIG. 20 is a diagram showing a comparison (target material 2) of the steel sheet temperature on the exit side of the fifth stand between the first invention and the conventional method. FIG. 21: Comparison of rolling speed distribution between the first invention and the conventional method
The figure which shows (target material 2). FIG. 22 is a view showing an example of application to a tandem rolling mill according to the first embodiment of the present invention, in which the supply position of a second supply system emulsion is set on the upstream side of a roll bite. [Description of References] 1 ... storage tank, 2 ... tank, 3 ... tank, 4 ... tank, 5a, 5b, 5c ... supply pump, 6a, 6b, 6
c, 6d: Flow control valve, 7: Stirrer, 8a, 8b: Pump, 9a, 9b: Rolling oil supply line, 10a, 10b ...
Header, 11 ... Rolling oil supply line, 12a, 12b ...
Flow control valves, 13a, 13b: circulation system tank, 14
a, 14b pump, 15a, 15b rolling oil supply line, 16 stirring pump, 17a, 17b recovery oil pan, 18 stirrer, 19a, 19b header, 2
0: cooling emulsion supply system, 21: strip,
22: Work roll, 23: Backup roll, 24
a, 24b: calculation device, 25: flow meter, 26a, 26b
... flow control valve, 27 ... stirring section, 28 ... pump,
29: flow regulating valve, 30a, 30b: return line, 31
... Flow control valve, 32 ... Piping, 33 ... Flow control valve, 34 ...
Stirring pump, 35 ... Piping, 36 ... Flow control valve, 37 ...
Flow control valve, 38: Piping, 39: Flow control valve, 40: Piping, 41: Pump, 42: Refill tank, 43a, 43
b, 43c: piping, 44a, 44b, 44c: flow control valve, 45: agitator, 46: refilling pump, 47: piping, 48: oil pan.

   ────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Yukio Kimura             1-2-1 Marunouchi, Chiyoda-ku, Tokyo Sun             Honko Tube Co., Ltd. (72) Inventor Yoshimi Sakurai             1-2-1 Marunouchi, Chiyoda-ku, Tokyo Sun             Honko Tube Co., Ltd. (72) Inventor Hiroyoshi Sakai             1-2-1 Marunouchi, Chiyoda-ku, Tokyo Sun             Honko Tube Co., Ltd. (72) Inventor Shigehiro Tomone             1-2-1 Marunouchi, Chiyoda-ku, Tokyo Sun             Honko Tube Co., Ltd. F-term (reference) 4E002 AD05 BC08 CB10

Claims (1)

Claims: 1. A first rolling oil supply system for supplying an emulsion rolling oil in cold rolling in a circulating manner, and a second rolling oil supply for supplying an emulsion rolling oil to upper and lower surfaces of a steel plate. A system is provided, and from the second rolling oil supply system, a surfactant having the same type as the emulsion of the first rolling oil supply system and having a lower oil concentration than the first rolling oil supply system is provided on the upper and lower surfaces of the steel sheet. Adding, further, supplying an emulsion adjusted to have an average particle size larger than that of the emulsion in the first rolling oil supply system, and recovering the emulsion that did not adhere to the steel sheet in this step. Adding a surfactant so as to have the same concentration as the surfactant in the oil supply system with respect to the oil concentration, adding mechanical stirring, and then joining the emulsion to the first rolling oil supply system emulsion. Specially Rolling oil supply method in the cold rolling mill to.