KR20020010191A - Cold rolling oil spray apparatus and the spray method having good surface cleaning degree of steel plate - Google Patents

Abstract

PURPOSE: An apparatus and a method for spraying a cold rolling mill lubricant having superior cleaning effect to strip surface are provided which improve cleanliness and greatly reduce residual iron powder on the surface of a cold steel sheet by maximizing the inherent cleaning effect of the rolling mill lubricant. CONSTITUTION: The apparatus for spraying a cold rolling mill lubricant comprises cutout valves(14,15) each of which are installed on a first supply line(103) and a first recovery guide line(104); cutout valves(20,19) each of which are installed on a first new liquid supply line(310) and a second new liquid supply line(309), wherein the second new liquid supply line(309) is connected to the first new liquid supply line(310); and a new rolling mill lubricant spray part which is equipped with a plurality of cutout valves and flowmeters and installed on the first supply line and the first recovery guide line, wherein the new rolling mill lubricant spray part further comprises a second supply tank(201), a pump(202) connected to the second supply tank, a second supply line(203) connected to the pump, a second recovery guide line(204) which is connected to the first recovery guide line at the lower part of a rolling mill, a second recovery tank(205) connected to the second recovery guide line, a pump(206) connected to the second recovery tank, a second recovery line(207) connected to the pump, and a rolling water transfer line installed between the second recovery line and the first recovery tank.

Description

Cold rolling oil spray apparatus and the spray method having good surface cleaning degree of steel plate}

The present invention relates to a cold rolled oil injector and a method thereof, and more particularly to a cold rolled oil injector and a method for excellent surface cleanliness of the steel sheet to improve the surface cleanliness of the cold rolled steel sheet during cold rolling operation.

1 is a configuration diagram showing a conventional cold rolled oil injection system. In general, a used rolling oil injection system in a cold rolling operation may include rolling oil between the rolls of the shear and final stand rolling mills 11 and 12 and the cold rolled steel sheet 10 during a rolling operation. It is used to ensure optimal lubricity and cleaning by spraying, and rolling mills 11 and 12 of all stands through the first supply line 103 by using the pump 102 to the rolling oil from the first supply tank 101 After the injection into the first collecting tank 105 through the first recovery induction line 104 in the bottom of the rolling mill (11, 12).

Thereafter, a circulation system for transferring the rolled oil back to the first supply tank 101 through the pump 106 and the first recovery line 107. At this time, the rolling oil that is buried on the surface of the cold rolled steel sheet 10 or is discharged as a fume during the continuous rolling operation is about 6 to 8 m 3 per hour, and requires continuous fresh liquid replenishment.

Conventional rolling oil replenishment liquid transfers a certain amount of the raw liquid from the raw liquid tank 301 to the intermediate mixing tank 307 through the pump 302 and the supply line 303, and pumps the pure water heated up from the pure water tank 304 305) and the feed line 306 are transferred to the intermediate mixing tank 307, and then diluted to an appropriate concentration for each thickness of the cold rolled steel sheet 10 to stand by, and then the water level of the first supply tank 101 is set. If it falls below, the pump 308 is operated to compensate the water level through the first new liquid supply line 310, and this operation is automatically performed through the sequence of the control computer.

At this time, in the conventional cold rolling oil injection system, a scum combined with oil is generated by the worn iron of the roll and the cold rolled steel sheet 10 generated during the continuous rolling operation, and contamination of the rolling oil is inevitable by the scum. Done.

As the contaminated rolling oil is sprayed on the rolling mills 11 and 12 of all the stands again, the cleaning effect is reduced during the cold rolling operation, and as a result, much residual iron and smudge remain on the surface of the cold rolled steel sheet 10. As a result, the whiteness indicating the cleanliness of the cold rolled steel sheet 10 is lowered, and there is a problem that causes degreasing during pretreatment of the annealing and plating processes, which are post processes.

The present invention has been made to solve the problems of the prior art as described above, cold rolled oil having excellent surface cleanliness of the steel sheet that can improve the cleanliness by maximizing the cleaning effect inherent in the rolling oil, and can significantly reduce the residual iron on the surface of the cold rolled steel sheet It is an object of the present invention to provide an injector and a method thereof.

1 is a configuration diagram showing a conventional cold rolling oil injection system

2 is a block diagram of a cold rolled oil injection device excellent in surface cleanliness of the steel sheet according to the present invention

3 is a flow chart showing a control pattern of the cold rolled oil injection method excellent surface cleanliness of the steel sheet according to the present invention

Fig. 4 is a graph comparing residual iron on the surface of a steel sheet according to the conventional method and the present invention.

10: cold rolled steel sheet 11: shear stand rolling mill

12: final stand rolling mill 201: second supply tank

203: second supply line 204: second recovery induction line

205: second recovery tank 207: second recovery line

208: rolling oil transfer line 301: liquid tank

304: pure water tank 307: intermediate mixing tank

309: second new liquid supply line

A rolling mill injection unit for recovering and recirculating the rolled oil injected into the rolling mill through the first supply line to achieve the above object and through the first and second recovery tanks; In the cold rolled oil injection device comprising a raw liquid and a pure water is transferred to the intermediate mixing tank, respectively, and including a rolling oil fresh liquid replenishment to compensate the level of the rolling oil through the first new liquid supply line, wherein the first supply line and the first recovery induction line Each of the blocking valves is installed at each of the two new liquid supply lines connected to the first new liquid supply line, and the blocking valves are installed at each line. Provided is a cold rolled oil injector excellent in surface cleanliness of a steel sheet, characterized in that a new rolled oil injector provided with a steel sheet is provided.

In the present invention, the new rolling oil injection unit includes a second supply tank, a pump connected to the second supply tank, a second supply line connected to the pump, and a first connected to the first recovery induction line under the rolling mill. A second recovery line, a second recovery tank connected to the second recovery guide line, a pump connected to the second recovery tank, a second recovery line connected to the pump, the second recovery line and the first recovery line It characterized in that it comprises a rolling water transfer line installed between the tank.

In addition, in the present invention, the second new liquid supply line is connected to the second supply tank, characterized in that for supplying the rolling oil of the intermediate mixing tank.

Further, according to the present invention, the rolling oil pumped from the first supply tank is sprayed to the rolling mills of all the stands through the first supply line, and the stock solution and the pure water respectively transferred to the intermediate mixing tank are diluted to an appropriate concentration and the first supply tank. In the cold rolled oil injection method to compensate for this when the water level drops, the rolling oil pumped from the first and second supply tanks is sprayed to the front stand rolling mill and the final stand rolling mill through the first and second supply lines, respectively, and used for the final stand rolling mill. And pumped from the second recovery tank connected to the second recovery induction line and re-injected into the front stand rolling mill through the second recovery line and the rolling oil transfer line, and the new rolling oil of the intermediate mixed tank supplies the second supply tank. Cold rolled oil injection method excellent in surface cleanliness of the steel sheet, characterized in that to be supplied to the final stand rolling mill through do.

Hereinafter, the present invention will be described in more detail with reference to the drawings showing preferred embodiments.

As shown in FIG. 2, in the cold rolled oil injection device having excellent surface cleanliness of the steel sheet according to the present invention, a cutoff valve 14 is provided in the first supply line 103 of the above-described used rolling oil injection unit, and the first A second supply line 203 having a shutoff side 13 is connected to the supply line 103, and the second supply line 203 is connected to the second supply tank 201 via a pump 202. It is connected.

In addition, the above-described first recovery induction line 104 is provided with a blocking side 15, the first recovery induction line 104 has a second recovery induction line 204 having a blocking side 16 is The second recovery guide line 204 is connected to the second recovery tank 205.

In addition, a second recovery line 207 is connected to the second recovery tank 205 via a pump 206, and a part of the rolling oil pumped from the second recovery tank 205 is the second supply tank. A part of the rolled oil is introduced into the first recovery tank 105 through the blocking side 17 of the rolled oil transfer line 208 branched from the second recovery line 207.

In addition, the second new liquid supply line having a blocking side 20 is provided in the first new liquid supply line 310 of the above-described rolling oil replenishment, and the blocking side 19 is provided in the first new liquid supply line 310. 309 is connected to the second supply tank 201, and reference numeral 18 in the figure is a flow meter.

On the other hand, the cold rolled oil injection method according to the present invention is carried out in the apparatus according to the present invention configured as described above, it will be described as follows.

As shown in FIG. 2, the rolling oil in the first supply tank 101 is transferred to the shear stand rolling mill 11 through the pump 102 and the first supply line 103, and is formed between the roll and the cold rolled steel sheet 10. The sprayed oil in the second supply tank 201 is transferred to the final stand rolling mill 12 through the pump 202 and the second supply line 203 and sprayed between the roll and the cold rolled steel sheet 10.

At this time, the blocking side 14 of the first supply line 103 is in a closed state, and the blocking side 13 of the second supply line 203 is in an open state so that the respective rolling oils are not mixed. to be.

The rolling oil sprayed on the shear stand rolling mill 11 is dropped to the lower portion and collected in the first recovery tank 105 underground serving as an intermediate buffer along the first recovery induction line 104. The final stand rolling mill 12 Rolled oil injected into the) is collected in the second recovery tank 205 along the second recovery induction line 204.

At this time, the blocking side 15 of the first recovery induction line 104 is in a closed state, and the blocking side 16 of the second recovery induction line 204 is in an open state so that the respective rolled oils are not mixed.

Meanwhile, the rolled oil collected in the first recovery tank 105 is transferred to the first supply tank 101 through the pump 106 and the first recovery line 107, and collected in the second recovery tank 205. The rolled oil is transferred to the second supply tank 201 through the pump 206 and the second recovery line 207, and at this time, a predetermined amount of the rolling oil of the second recovery line 207 is transferred to the first recovery tank 105. The blocking side 17 of the rolling oil transfer line 208 is in a closed state.

As described above, the rolling oil continuously circulated during the cold rolling operation has both water tanks lowered due to the amount attached to the surface of the cold rolled steel sheet 10 and the amount discharged into the fume, in which case the first supply tank ( When the water level of the 101 drops, the cut edge 17 of the rolled oil transfer line 208 is opened, and the rolled oil to be transferred is detected and integrated by the flow meter 18, and when the flow rate reaches a constant flow rate, the cut edge 17 ) Is closed, and the rolled oil transferred to the first recovery tank 105 is transferred to the first supply tank 101 again, so that the water level of the first supply tank 101 is restored to a normal level, and thus to the shear stand rolling mill 11. Rolling oil spray operation can be performed smoothly.

On the other hand, the level of the second supply tank 201 is relatively reduced by the rolling oil transferred to the first recovery tank 105, the replenishment is made by the new rolling oil of the intermediate mixing tank 307, The supplementary method is as follows.

The shut-off side 19 of the second new liquid supply line 309 is opened to transfer the rolled oil of the intermediate mixing tank 307, which has been diluted in advance, to the second supply tank 201, and the pump 308 After the rolled oil is transferred to the minimum level of the intermediate mixing tank 307, the pump 308 is stopped and the shutoff valve 19 is closed, at which time the shutoff valve 20 of the first new fluid supply line 310 is closed. Is closed.

Subsequently, the crude oil of the crude liquid tank 301 and the pure water heated in the pure water tank 304 are transferred to the intermediate mixing tank 307 through the pumps 302 and 305 of the supply lines 303 and 306.

In this way, the unused clean rolling oil is continuously supplied to the second supply tank 201 and sprayed to the final stand rolling mill 12, and the sprayed rolling oil is supplied to the rolling oil transfer line 208 when the level of the first supply tank 101 falls. The transfer through) is repeated.

Rolling oil refilling operation as described above is automatically performed by the above-described sequence of the control computer, and if it is described with reference to Figure 3 after determining whether the injection system for rolling oil injection is operating normally (31), The first supply tank 101 checks the water level drop 32, and the second supply tank 201 checks the water level drop 37, when the rolling oil of the first supply tank 101 is below a predetermined level. When the water level compensation work of the tank 101 is carried out 34, and a certain amount of the rolled oil is transferred 35, the blocking side 17 of the rolling oil transfer line 208 is closed 36 to finish the water level compensation work.

Thereafter, the system goes back to the normal operation determination step 31, and when the rolling oil of the second supply tank 201 is below a predetermined level, the level compensation operation of the second supply tank 201 is performed 38, and the intermediate mixed tank When the new rolling oil replenishment operation to the second supply tank 201 through 307 is completed (39), the crude oil of the crude liquid tank 301 and the pure water of the pure water tank 304 to the intermediate mixing tank 307 After performing the supplementary work (40), the system goes back to the normal operation determination step (31).

According to the present invention as described above, the contaminated rolling oil is injected into the shear stand rolling mill 11 of the cold rolled steel sheet 10 as before, but the final rolling mill 12, which is the last rolling step, is cleanly charged with new rolling oil concentrate. As the rolling oil is injected and sprayed, it is possible to produce a cold rolled steel sheet 10 having excellent surface cleanliness by maximizing the cleaning effect inherent to the rolling oil, and as shown in FIG. 4, a cold rolled steel sheet as a standard representing cleanliness of the surface of the cold rolled steel sheet 10. (10) It can be seen that the residual iron on the surface is greatly reduced to about 1/2 level compared with the conventional method.

As described above, according to the present invention, the contaminated rolling oil is sprayed on the shear stand rolling mill, and the final rolling mill, which is the final rolling stage, is supplied with clean rolling oil, thereby making it possible to manufacture cold rolled steel sheets having high cleanliness and surface of the cold rolled steel sheet. There is a useful effect that the residual iron in is greatly reduced.

Claims (4)

A use-rolling part spraying unit in which rolling oil sprayed to the rolling mill through the first supply line is recovered and recycled through the first recovery induction line and the first recovery tank; In the cold rolled oil injection device comprising a raw material and pure water are each transferred to the intermediate mixing tank, and including a rolling oil fresh liquid replenishment portion for compensating the level of the rolling oil through the first new liquid supply line, Shut-off sides are respectively installed in the first supply line and the first recovery induction line, The second new liquid supply line is connected to the first new liquid supply line, and a blocking valve is installed in each line. Cold rolling oil injector having excellent surface cleanliness of the steel sheet, characterized in that a new rolling oil injection unit having a plurality of shut-off sides and flow meters are installed in the first supply line and the first recovery induction line. According to claim 1, wherein the new rolling oil injection unit, the second supply tank, the pump connected to the second supply tank, the second supply line connected to the pump, and connected to the first recovery induction line at the bottom of the rolling mill A second recovery induction line, a second recovery tank connected to the second recovery induction line, a pump connected to the second recovery tank, a second recovery line connected to the pump, the second recovery line and the first Cold rolled oil injection device excellent in the cleanliness of the surface of the steel sheet, characterized in that it comprises a rolling water transfer line provided between the recovery tank. The cold rolled oil injection device of claim 1 or 2, wherein the second new liquid supply line is connected to the second supply tank to supply the rolling oil of the intermediate mixing tank. Injecting the rolling oil pumped from the first supply tank to the rolling mills of all the stands through the first supply line, diluting the stock solution and the pure water respectively transferred to the intermediate mixing tank to an appropriate concentration to replenish it when the water level of the first supply tank falls. In cold rolled oil injection method, The rolling oil pumped from the first and second supply tanks is sprayed to the front stand rolling mill and the final stand rolling mill through the first and second supply lines, respectively, and the second recovery water connected to the second recovery induction line is used for the rolling oil used in the final stand rolling mill. Pumping from the tank to the second recovery line and Re-injected into the front stand rolling mill through a rolling oil conveying line, and cold rolled oil injection having excellent surface cleanness of the steel sheet, characterized in that the new rolling oil of the intermediate mixing tank is supplied to the final stand rolling mill through the second supply tank. Way.