JP2015147230A - Lubrication device and lubrication method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lubrication device and a lubrication method allowing for prevention of the occurrence of mottling on the surface of a metal plate while securing lubricity of a roll-bite necessary upon cold rolling of the metal plate.SOLUTION: The lubrication device in one embodiment of the present invention imparts lubricity between a rolling roller of a cold rolling mill and a metal plate as a cold rolling object, and includes a rust prevention treatment part, a lubricant supply part and a control part. The rust prevention treatment part applies rust prevention oil onto the surface of the metal plate to subject the metal plate to rust prevention treatment. The lubricant supply part supplies onto an interlayer between the rolling roller of the cold rolling mill which performs cold rolling on the metal plate subjected to the rust prevention treatment and the metal plate subjected to the rust prevention treatment, a water-soluble lubricant which has not a cloud point equal to or below the temperature of the interlayer. The control part sets an application oil amount of the rust prevention oil in accordance with a draft when subjecting the metal plate subjected to the rust prevention treatment to cold rolling with the cold rolling mill and controls the rust prevention treatment part so as to apply the rust prevention oil of the set application oil amount onto the surface of the metal plate.

Description

  The present invention relates to a lubricating device and a lubricating method for imparting lubricity between a rolling roll of a cold rolling mill and a metal plate to be rolled.

  As an example of a technique for manufacturing a steel sheet as a base for a hard tin plate or the like that is a material for food cans, a double reduction rolling (hereinafter abbreviated as DR rolling) method has been known. In general, the DR rolling method performs cold rolling with a rolling reduction of about 10 to 30% on a cold rolled steel sheet manufactured by sequentially performing each processing step of a steel sheet from hot rolling to cold rolling to annealing. It is a rolling method applied again. According to this DR rolling method, it is possible to produce a steel plate suitable as a base for hard tin or the like, that is, a steel plate that is hard and thin.

  In the cold rolling process of the steel sheet applied to the DR rolling method as described above, the rolling load may be excessively increased because a hard cold rolled steel sheet is manufactured. As a result, problems such as plate breakage due to the restriction occur. In order to solve such a problem, in the cold rolling process of the steel sheet, lubricating oil is introduced into a steel sheet region (hereinafter referred to as a roll bite) that is bitten by a rolling roll of a cold rolling mill, Lubricity is imparted between the rolling roll and the steel plate surface. Hereinafter, the lubricity between the rolling roll and the steel sheet surface in the roll bit is abbreviated as “lubricating property of roll bit” as appropriate.

  As the lubricating oil introduced into the roll bite, usually an emulsion rolling oil is used. Emulsion rolling oil is a mixed liquid in which oil component particles are stably suspended in water (emulsion state). In general, an emulsion rolling oil is characterized by an emulsion concentration, which is a ratio of the amount of oil substance in the total mass, and an average particle diameter of an oil component (hereinafter referred to as rolling oil as appropriate) contained in the emulsion rolling oil. . The emulsion rolling oil is prepared by adding a surfactant or the like to an oil-water mixed liquid of rolling oil and water. In the production of the emulsion rolling oil, the surfactant is added so that the mass concentration (to the oil concentration) with respect to the amount of rolling oil becomes a predetermined value. The average particle diameter of the emulsion rolling oil is adjusted by applying shearing with a stirrer and a pump to the oil / water mixed liquid after the addition of the surfactant and the like.

  On the other hand, on the surface of a steel plate manufactured by a cold rolling process such as the DR rolling method, white spot-like spots called mottling may occur. Motoring is the result of oil droplets in the lubricating oil (specifically, emulsion rolling oil) used as a coolant during cold rolling of steel sheets agglomerating and coarsening and being rolled into a roll bite. This occurs because of mottled distribution (see Non-Patent Document 1). The motoring generated on the surface of the steel sheet becomes clearer by the electroplating process of the steel sheet performed after cold rolling such as DR rolling, and as a result, the appearance of the steel sheet surface is significantly impaired. The appearance of the steel sheet surface where such motoring has occurred is not acceptable as a steel sheet product, and is particularly unsuitable as a food can material. In addition, although the appearance defect mentioned above may be called a stain by the form, below, the description is unified to mottling irrespective of the form of appearance defect.

  As a conventional technique for suppressing such motoring during DR rolling, for example, a solution type lubricant in which a water-soluble substance (lubricant) is dissolved in water instead of an emulsion type lubricant, that is, an emulsion rolling oil, is used. There is one that uses a coolant having a liquid temperature equal to or higher than the cloud point to a roll bite to perform DR rolling on a steel sheet as a coolant (see Patent Document 1).

JP 2006-272402 A

"Theory and Practice of Plate Rolling", published by Japan Iron and Steel Institute, 1984, p.216

  In the above-described conventional technology, a solution type lubricant (hereinafter referred to as a water-soluble lubricant) introduced into a roll bite when cold-rolling a steel sheet reaches a cloud point or higher with processing heat generation in the roll bite. The lubrication effect is expressed by agglomeration of the polymer as the lubricating component in the water-soluble lubricant. However, in cold rolling under relatively high pressure exemplified by the DR rolling method, the processing heat generation is large, so the liquid temperature of the water-soluble lubricant in the roll bite may increase rapidly. The polymer which is a lubricating component in the lubricant is irregularly aggregated and coarsened. As a result, there is a possibility that a pseudo oil pit that may cause motoring is generated on the surface of the steel sheet.

  The present invention has been made in view of the above circumstances, and prevents the occurrence of motoring on the surface of a metal plate while ensuring the lubricity of a roll bite necessary during cold rolling of a metal plate such as a steel plate. It is an object of the present invention to provide a lubricating device and a lubricating method capable of performing the above.

  In order to solve the above-described problems and achieve the object, a lubrication apparatus according to the present invention lubricates between a rolling roll of a cold rolling mill that cold-rolls a metal plate and the metal plate to be cold-rolled. In the lubricating device for imparting the property, the surface of the metal plate is coated with rust-preventive oil to rust-proof the metal plate, and the metal plate after the rust-proofing is cold-rolled Lubricant supply unit for supplying a water-soluble lubricant having no cloud point below the temperature of the interface to the interface between the rolling roll of the cold rolling mill and the metal plate after the antirust treatment, and the cold rolling According to the reduction ratio when the metal plate after the rust prevention treatment is cold-rolled by a machine, the amount of the rust prevention oil is set, and the rust prevention oil of the set oil amount is set to the metal plate. And a controller for controlling the rust preventive unit so as to apply oil to the surface of the rust preventive.

  Further, the lubricating device according to the present invention is characterized in that, in the above invention, the water-soluble lubricant contains a fatty acid having a carbon chain number larger than the carbon chain number of the oil component of the rust preventive oil. To do.

  Further, in the above invention, the lubricating device according to the present invention is an emulsion rolling oil when the water-soluble lubricant is supplied between a rolling roll of the cold rolling mill and the metal plate after the rust prevention treatment. Necessary oil amount information indicating the correlation between the required oil amount of the rust preventive oil required to obtain the same level of lubricity and the reduction ratio of the metal plate after the rust preventive treatment by the cold rolling mill is stored. A storage unit is further provided, and the control unit derives and derives a necessary oil amount of the rust preventive oil according to a reduction ratio of the metal plate after the rust preventive treatment based on the required oil amount information. The rust preventive section is controlled so that the surface of the metal plate is coated with the rust preventive oil in excess of the required amount of oil applied.

In the lubricating device according to the present invention, in the above invention, the amount of the antirust oil applied to the metal plate is 10 [mg / m ² ] or more and 150 [mg / m ² ] or less. Features.

In the lubricating device according to the present invention, the kinematic viscosity at 40 [° C.] of the antirust oil is less than 15 [mm ² / s] in the above invention.

  Further, the lubrication method according to the present invention includes the cold rolling in the lubrication method for imparting lubricity between a rolling roll of a cold rolling mill for cold rolling a metal plate and the metal plate to be cold rolled. An oil application amount setting step for setting an oil application amount of the antirust oil to the metal plate according to a reduction ratio when the metal plate is cold-rolled by a machine, and the antirust oil of the set oil application amount. A surface of the metal plate, and a rust-preventing step for rust-proofing the metal plate; and a rolling roll and a rust-proofing device for cold-rolling the metal plate after the rust-proofing treatment And a lubricant supply step of supplying a water-soluble lubricant having no cloud point below the temperature of the interface at the interface with the metal plate after the treatment.

  Moreover, the lubricating method according to the present invention is characterized in that, in the above invention, the water-soluble lubricant contains a fatty acid having a carbon chain number larger than the carbon chain number of the oil component of the rust preventive oil. To do.

  Further, in the lubricating method according to the present invention, in the above invention, the oil application amount setting step may include the water-soluble lubricant between a rolling roll of the cold rolling mill and the metal plate after the antirust treatment. The correlation between the required amount of the rust preventive oil required to obtain the same level of lubricity as that of the emulsion rolling oil when supplied and the reduction ratio of the metal plate after the rust prevention treatment by the cold rolling mill is shown. Based on the required oil amount information, the required oil amount of the antirust oil is derived according to the reduction ratio of the metal plate after the antirust treatment, and the oil amount of the antirust oil is determined as the required oil amount. The rust prevention treatment step is characterized in that the rust preventive oil is applied to the surface of the metal plate while controlling the oil application amount of the rust preventive oil to be equal to or greater than the required oil application amount. And

In the lubricating method according to the present invention, the amount of the rust preventive oil applied to the metal plate is 10 [mg / m ² ] or more and 150 [mg / m ² ] or less in the above invention. Features.

In the lubricating method according to the present invention, the kinematic viscosity at 40 [° C.] of the rust preventive oil is less than 15 [mm ² / s] in the above invention.

  ADVANTAGE OF THE INVENTION According to this invention, there exists an effect that generation | occurrence | production of the motoring of a metal plate surface can be prevented, ensuring the lubricity of the roll bite required at the time of the cold rolling of a metal plate.

FIG. 1 is a diagram illustrating a configuration example of a lubrication apparatus according to an embodiment of the present invention. FIG. 2 is a diagram showing an example of the correlation between the required amount of rust preventive oil applied to the steel sheet and the reduction ratio in cold rolling of the steel sheet after the rust prevention treatment. FIG. 3 is a flowchart showing an example of the lubrication method according to the embodiment of the present invention.

  Exemplary embodiments of a lubricating device and a lubricating method according to the present invention will be explained below in detail with reference to the accompanying drawings. Note that the present invention is not limited to the embodiment.

  FIG. 1 is a diagram illustrating a configuration example of a lubrication apparatus according to an embodiment of the present invention. FIG. 1 schematically shows a rear half portion of a rolling line 20 and a DR rolling line 30 as an example of a steel sheet production line to which the lubricating device 1 according to the present embodiment is applied. Further, in FIG. 1, a thick arrow indicates a conveyance direction of the steel plate 15 or the coil 16 to be processed. Below, the structure of the rolling line 20 and DR rolling line 30 is demonstrated first, and the structure of the lubrication apparatus 1 concerning this Embodiment 1 is demonstrated after that.

(Steel plate production line)
The rolling line 20 is a manufacturing line for performing cold rolling and the like at the first stage in the DR rolling method on the steel plate 15 to be processed. Specifically, as shown in FIG. 1, the rolling line 20 includes a continuous annealing equipment 21 and a winding device 22. Although not particularly shown in FIG. 1, the rolling line 20 includes a heating furnace for heating the steel slab, and a hot rolling mill (rough rolling) for producing the steel plate 15 by continuously hot rolling the steel slab in a high temperature state. Machine, finish rolling mill), a cold rolling mill for cold rolling the steel plate 15 after the cooling treatment, a transport roll for transporting the steel slab or the steel plate 15 from the heating furnace side toward the winding device side, and the like.

  In the rolling line 20, the hot rolling mill continuously hot-rolls the steel slab heated by the heating furnace, thereby processing the steel slab into the steel plate 15. A cold rolling mill cold-rolls the steel plate 15 (hot-rolled steel plate) manufactured by hot rolling after cooling processing. The cold rolling of the steel sheet 15 by the cold rolling mill of the rolling line 20 corresponds to the first stage cold rolling in the DR rolling method.

  The continuous annealing equipment 21 is installed in the next process of the above-described cold rolling mill (not shown) in the rolling line 20. The continuous annealing equipment 21 continuously anneals the steel sheet 15 while receiving the steel sheet 15 (cold rolled steel sheet) sequentially conveyed from the exit side of the cold rolling mill. Moreover, as shown in FIG. 1, the continuous annealing equipment 21 is provided with the rust prevention processing part 2 in the latter half. The rust prevention treatment part 2 is one component part of the lubrication apparatus 1 according to the present embodiment, and rust prevention treatment is performed on the surface of the steel plate 15 after annealing by application of rust prevention oil. The continuous annealing equipment 21 sequentially carries out the steel plate 15 after such rust prevention treatment toward the winding device 22. The winding device 22 is configured using a mandrel or the like, and is installed at the exit end of the rolling line 20 as shown in FIG. The winding device 22 sequentially winds the steel plate 15 continuously annealed and rust-proofed by the continuous annealing equipment 21 into a coil shape, and turns the steel plate 15 after the rust-proofing treatment into a coil 16. The coil 16 is stored as necessary and is put into the DR rolling line 30 at a desired timing.

  The DR rolling line 30 is a production line for performing cold rolling or the like at the second stage in the DR rolling method on the steel plate 15 to be processed. Specifically, as shown in FIG. 1, the DR rolling line 30 includes a payoff reel 31, a DR rolling facility 34, an entry side bridle roll 35, an exit side bridle roll 36, and a tension reel 37. Although not shown in FIG. 1, the DR rolling line 30 appropriately includes a transport roll for transporting the steel plate 15 from the payoff reel 31 side toward the tension reel 37 side.

  The payoff reel 31 is a device that sequentially pays out the steel plates 15 to be processed into the DR rolling line 30, and is installed at the entrance end of the DR rolling line 30 as shown in FIG. 1. The payoff reel 31 receives the coil 16 manufactured by the rolling line 20 described above, and sequentially pays out the steel plate forming the received coil 16, that is, the steel plate 15 after the rust prevention treatment, toward the entry bridle roll 35. .

  The entry-side bridle roll 35 is configured by using a pair of rolls whose outer peripheral surfaces are opposed to each other, and is installed at the rear stage of the payoff reel 31 as shown in FIG. The entry-side bridle roll 35 sequentially receives the steel plates 15 paid out from the coil 16 by the payoff reel 31, and applies tension to the received steel plates 15, thereby reducing distortion and bending wrinkles of the steel plates 15. The steel plates 15 processed by the entry-side bridle roll 35 are sequentially conveyed toward the DR rolling equipment 34.

  The DR rolling equipment 34 performs cold rolling at the second stage in the DR rolling method on the steel plate 15 and is composed of two stands of cold rolling mills 32 and 33 as shown in FIG. The cold rolling mill 32 includes a pair of rolling rolls 32a and 32b that sandwich the steel plate 15 in the vertical direction, a pair of backup rolls corresponding to the rolling rolls 32a and 32b, and the like. Similarly, the cold rolling mill 33 includes a pair of rolling rolls 33a and 33b and a pair of backup rolls. Moreover, as shown in FIG. 1, one cold rolling mill 32 of the DR rolling equipment 34 is installed in the rear stage of the entry side bridle roll 35, and the other cold rolling mill 33 is this cold rolling mill. 32 is installed in the subsequent stage. Of these two stands of cold rolling mills 32 and 33, the second stage cold rolling in the DR rolling method is mainly performed by the preceding cold rolling mill 32. Specifically, the cold rolling mill 32 sequentially receives the steel plates 15 from the entry-side bridle roll 35, and is cold with a predetermined reduction rate (for example, a reduction rate of 10 to 30 [%]) with respect to the received steel plates 15. Roll sequentially. The steel plates 15 after the cold rolling by the cold rolling mill 32 are sequentially conveyed toward the subsequent cold rolling mill 33. The subsequent cold rolling mill 33 sequentially receives the cold-rolled steel plates 15 from the previous cold rolling mill 32 and has a smaller rolling reduction than the preceding cold rolling mill 32 with respect to the received steel plates 15. Cold rolling under light pressure is performed sequentially. Thereby, the cold rolling mill 33 adjusts the surface roughness of the steel plate 15 after the cold rolling by the cold rolling mill 32 described above. The steel plates 15 after cold rolling under light pressure by the cold rolling mill 33 are sequentially conveyed toward the exit side bridle roll 36.

  The exit-side bridle roll 36 is configured by using a pair of rolls whose outer peripheral surfaces are opposed to each other, and is installed at the rear stage of the cold rolling mill 33 as shown in FIG. The exit side bridle roll 36 sequentially receives the steel plates 15 after the cold rolling by the cold rolling mill 33 and applies tension to the received steel plates 15 to reduce distortion and bending wrinkles of the steel plates 15. The steel plates 15 processed by the exit side bridle roll 36 are sequentially conveyed toward the tension reel 37.

  The tension reel 37 is a device that sequentially winds the steel plate 15 that has been cold-rolled in the second stage of the DR rolling method in the DR rolling line 30, and as shown in FIG. Installed. The tension reel 37 sequentially winds the steel plate 15 conveyed from the exit side bridle roll 36 into a coil shape, and uses the steel plate 15 after this cold rolling (after DR rolling) as the coil 17. Thereafter, the coil 17 is shipped as a product, or is subjected to predetermined processing in another process as necessary.

(Lubrication device)
Next, the configuration of the lubricating device 1 according to the embodiment of the present invention will be described with reference to FIG. The lubrication apparatus 1 is an apparatus that imparts lubricity between the rolling rolls 32a, 32b, 33a, 33b of the cold rolling mills 32, 33 and the steel sheet 15 to be cold rolled, and includes a rolling line 20 and a DR rolling line. 30. As shown in FIG. 1, such a lubrication apparatus 1 includes a rust prevention treatment unit 2, a lubricant tank 3, a supply pipe 4, a pump 5, lubricant supply units 6 a to 6 d, a cooling spray 7 a, 7b and air injection portions 8a and 8b. The lubrication apparatus 1 also includes a storage unit 9 that stores information necessary for controlling the amount of rust preventive oil applied to the steel plate 15 and a control unit 10.

The rust prevention treatment unit 2 applies a rust prevention oil to the surface of the steel plate 15 to rust prevent the steel plate 15. Specifically, as shown in FIG. 1, the rust prevention treatment unit 2 is incorporated in a continuous annealing facility 21. As described above, the continuous annealing equipment 21 continuously anneals the steel plates 15 that are sequentially conveyed. The rust prevention treatment unit 2 sequentially coats the surface of the steel plate 15 being continuously annealed in this manner with a predetermined rust preventive oil in a substantially uniform manner, thereby covering the entire surface of the steel plate 15. The steel plate 15 is rust-proofed. Here, the rust preventive oil coating method for the steel plate 15 of the rust preventive treatment unit 2 may be any oil coating method such as an electrostatic method, a direct coating method, or a roll coater method. From the viewpoint that it is easy to uniformly apply rust preventive oil to the surface, it is desirable to be an electrostatic system. The rust preventive oil used for the rust preventive treatment of the steel plate 15 described above may be any desired one. For example, in the tinplate and tin plate described in Japanese Industrial Standard (JIS G3303-2008), surface coating It is desirable that the oil is rust preventive oil. That is, the kinematic viscosity at 40 [° C.] of the rust preventive oil in the present invention is desirably less than 15 [mm ² / s]. In particular, from the viewpoint of rust prevention performance and availability, the rust prevention oil in the present invention is desirably any of mineral oil such as dioctyl sebacate, cottonseed oil, or synthetic oil such as tributyl acetylcitrate.

  The lubricant tank 3 stores the water-soluble lubricant 12 supplied between the rolling rolls 32 a, 32 b, 33 a, 33 b of the cold rolling mills 32, 33 and the steel plate 15, and prepares the water-soluble lubricant 12. It has the function to do. In the present embodiment, the lubricant tank 3 is charged with a necessary amount of water-soluble lubricant stock solution and diluted water, respectively. Lubricant tank 3 stores the supplied water-soluble lubricant stock solution and dilution water, and stirs and mixes the stored water-soluble lubricant stock solution and dilution water. Thereby, the lubricant tank 3 dilutes the water-soluble lubricant stock solution to a concentration suitable as a lubricant (for example, about 3 to 10 [mass%]) to obtain desired properties (lubricating components, concentration, temperature, etc.). A liquid water-soluble lubricant 12 is prepared. The lubricant tank 3 has a heat retaining mechanism (not shown), and stores the obtained water-soluble lubricant 12 while maintaining the temperature range below its cloud point.

  Here, the lubricating component contained in the water-soluble lubricant 12 is a water-soluble lubricating material (hereinafter referred to as a soluble lubricating material), and a roll bite between the DR rolling equipment 34 and the steel plate 15 after the rust prevention treatment. The external appearance of the water-soluble lubricant 12 can be maintained transparent or translucent in an environment of heat generation (processing heat generation, frictional heat generation, etc.). As long as the above conditions are satisfied, the type of the soluble lubricant contained in the water-soluble lubricant 12 is not particularly limited. For example, the soluble lubricant is chemically synthesized from the viewpoint of ease of designing the lubricity. A lubricating material is desirable. The water-soluble lubricant 12 containing such a soluble lubricant as a lubricating component is equal to or lower than the temperature at the interface between the rolling rolls 32a, 32b, 33a, 33b of the cold rolling mills 32, 33 and the steel plate 15 after the rust prevention treatment. Has no cloud point.

  Moreover, the water-soluble lubricant 12 contains a fatty acid having a carbon chain number larger than the carbon chain number of the oil component of the rust preventive oil in the rust preventive part 2 as an additive for supplementing the lubricity. To do. The amount of fatty acid added to the water-soluble lubricant 12 is preferably 10 [% by mass] or less. This is because when the amount of fatty acid added exceeds 10 [mass%], the oiliness of the water-soluble lubricant 12 increases, and as a result, the surface of the steel plate 15 is likely to be mottling. In the present invention, the type of fatty acid contained in the water-soluble lubricant 12 is not particularly limited, but it is desirable to add a fatty acid used as a general cold rolling oil to the water-soluble lubricant 12.

  Furthermore, the water-soluble lubricant 12 is used as an additive other than the above-described fatty acids in ordinary cold rolling oils such as extreme pressure additives, antioxidants, water-soluble rust preventives, antifoaming agents, and preservatives. You may contain an additive suitably. For example, as an extreme pressure additive, one or more selected from chlorinated compounds such as chlorinated oils and fats and chlorinated fatty acid esters, synthetic sulfur compounds such as sulfurized oils and fats and alkylpolysulfides, phosphorus compounds, and organometallic salt compounds These materials can be used. Moreover, what added alkanolamine etc. as a basic substance to fatty acids, such as aliphatic monocarboxylic acid, can be used as a water-soluble rust preventive agent, for example.

  The supply pipe 4 is a pipe that guides the water-soluble lubricant 12 from the lubricant tank 3 to the lubricant supply units 6a to 6d and the cooling sprays 7a and 7b. Specifically, as shown in FIG. 1, the supply pipe 4 includes a plurality of branch pipes 4 a to 4 c that branch into the inlet side and the outlet side of the two stand cold rolling mills 32 and 33 that constitute the DR rolling facility 34. Have The branch pipes 4a and 4c branch from the main pipe of the supply pipe 4 toward the entry sides of the cold rolling mills 32 and 33, respectively, and are connected to each pair of the plurality of pairs of lubricant supply units 6a to 6d. The branch pipe 4b branches from the main pipe of the supply pipe 4 toward the exit side of the cold rolling mill 32, and is connected to a pair of cooling sprays 7a and 7b. The supply pipe 4 has an input end connected to the lubricant tank 3 and communicates the lubricant tank 3 with the lubricant supply units 6a to 6d and the cooling sprays 7a and 7b via the branch pipes 4a to 4c. Such a supply pipe 4 guides the water-soluble lubricant 12 from the lubricant tank 3 to the lubricant supply parts 6a to 6d and the cooling sprays 7a and 7b through the branch pipes 4a to 4c.

  The pump 5 distributes the water-soluble lubricant 12 from the lubricant tank 3 through the supply pipe 4 to the lubricant supply units 6a to 6d and the cooling sprays 7a and 7b. Specifically, as shown in FIG. 1, the pump 5 is provided in the middle of the supply pipe 4. The pump 5 sucks the water-soluble lubricant 12 in the lubricant tank 3 into the supply pipe 4 and pumps the water-soluble lubricant 12 toward the output ends of the branch pipes 4 a to 4 c of the supply pipe 4.

  The lubricant supply units 6a to 6d are provided at the interface between the rolling rolls 32a, 32b, 33a, 33b of the cold rolling mills 32, 33 for cold rolling the steel plate 15 after the rust prevention treatment and the steel plate 15 after the rust prevention treatment. The water-soluble lubricant 12 having no cloud point below the interface temperature is supplied. Specifically, each of the lubricant supply units 6a to 6d is configured using a spray nozzle or the like. As shown in FIG. 1, the lubricant supply units 6 a and 6 b are connected to the output end of the branch pipe 4 a of the supply pipe 4, and are cold rolled 32 so as to face the plate thickness direction (vertical direction) of the steel plate 15. It is arranged on the entrance side. In this arrangement state, the upper lubricant supply unit 6 a directs the nozzle port toward the entry side of the rolling roll 32 a of the cold rolling mill 32. The lower lubricant supply unit 6 b directs the nozzle port toward the entry side of the rolling roll 32 b of the cold rolling mill 32. The lubricant supply units 6a and 6b receive the water-soluble lubricant 12 from the lubricant tank 3 through the branch pipe 4a and the like, and the received water-soluble lubricant 12 is rust-proofed with the rolling rolls 32a and 32b of the cold rolling mill 32. It sprays and supplies to the interface with the steel plate 15 after a process. Thereby, lubricant supply parts 6a and 6b supply water-soluble lubricant 12 which does not have a cloud point below the temperature of this interface to a roll bit in cold rolling mill 32 of steel plate 15 after rust prevention processing. . Similarly, the lubricant supply units 6 c and 6 d are connected to the output end of the branch pipe 4 c of the supply pipe 4 and are arranged on the inlet side of the cold rolling mill 33 so as to face the plate thickness direction of the steel plate 15. The In this arrangement state, the upper lubricant supply unit 6 c directs the nozzle port toward the entry side of the rolling roll 33 a of the cold rolling mill 33. The lower lubricant supply unit 6 d directs the nozzle port toward the entry side of the rolling roll 33 b of the cold rolling mill 33. The lubricant supply units 6c and 6d receive the water-soluble lubricant 12 from the lubricant tank 3 through the branch pipe 4c and the like, and the received water-soluble lubricant 12 is rust-proofed with the rolling rolls 33a and 33b of the cold rolling mill 33. It sprays and supplies to the interface with the steel plate 15 after a process. Thereby, lubricant supply parts 6c and 6d supply water-soluble lubricant 12 which does not have a cloud point below this interface temperature to a roll bit in cold rolling mill 33 of steel plate 15 after rust prevention processing. .

  The cooling sprays 7a and 7b inject and supply the water-soluble lubricant 12 as coolant to the rolling rolls 32a and 32b of the cold rolling mill 32. Specifically, as shown in FIG. 1, the cooling sprays 7 a and 7 b are connected to the output end of the branch pipe 4 b of the supply pipe 4 and are arranged in the cold rolling mill 32 so as to face the plate thickness direction of the steel plate 15. Arranged on the exit side. In this arrangement state, the upper cooling spray 7 a directs the nozzle opening toward the backup roll corresponding to the rolling roll 32 a of the cold rolling mill 32. The lower cooling spray 7 b directs the nozzle opening to a backup roll corresponding to the rolling roll 32 b of the cold rolling mill 32. The cooling sprays 7 a and 7 b receive the water-soluble lubricant 12 from the lubricant tank 3 through the branch pipe 4 b and the like, and spray the received water-soluble lubricant 12 to each backup roll of the cold rolling mill 32. The cooling sprays 7a and 7b supply the water-soluble lubricant 12 as a coolant to the rolling rolls 32a and 32b via the backup rolls. Thereby, the cooling sprays 7 a and 7 b cool the backup rolls and the rolling rolls 32 a and 32 b of the cold rolling mill 32 to a temperature suitable for cold rolling of the steel plate 15.

  The air injection parts 8a and 8b are for removing the water-soluble lubricant 12 remaining on the steel sheet 15 after cold rolling. Specifically, as shown in FIG. 1, the air injection unit 8 a is disposed between the first stand cold rolling mill 32 and the second stand cold rolling mill 33 of the DR rolling facility 34. The The air injection unit 8a injects air onto the upper surface of the steel plate 15 after being cold-rolled by the cold rolling mill 32, thereby removing the water-soluble lubricant 12 from the upper surface of the steel plate 15 after the cold rolling. To do. On the other hand, the air injection part 8b is arrange | positioned in the back | latter stage of the cold rolling mill 33 of the 2nd stand, as shown in FIG. The air injection unit 8b injects air onto the upper surface of the steel plate 15 after being cold rolled by the cold rolling mill 33, thereby removing the water-soluble lubricant 12 from the upper surface of the steel plate 15 after the cold rolling. To do.

  The storage unit 9 stores information necessary for controlling the amount of rust preventive oil applied to the surface of the steel plate 15 by the rust preventive processing unit 2 described above. Specifically, the storage unit 9 stores necessary oil amount information 9a as shown in FIG. The necessary oil amount information 9a is obtained when the water-soluble lubricant 12 is supplied between the rolling rolls 32a, 32b, 33a, 33b of the cold rolling mills 32, 33 and the steel plate 15 after the rust prevention treatment. The correlation between the required amount Qb of the rust preventive oil required to obtain the same level of lubricity and the reduction ratio Pr of the steel plate 15 after the rust preventive treatment cold rolled by the cold rolling mills 32 and 33 is shown. Information. The storage unit 9 includes a necessary amount Qb of rust preventive oil and a rust preventive treatment according to cold rolling conditions such as a metal type (steel type) and size (plate width, plate thickness, etc.) of the steel plate 15 to be cold rolled. Each piece of information indicating the correlation with the reduction ratio Pr of the steel plate 15 is held and managed as necessary oil amount information 9a. In addition, the storage unit 9 transmits information instructed to be read out by the control unit 10 from the necessary oil amount information 9 a to the control unit 10.

  The control unit 10 controls the amount of rust preventive oil applied to the surface of the steel plate 15 by the rust preventive processing unit 2 described above. Specifically, the control unit 10 acquires the cold rolling conditions of the steel plate 15 by the cold rolling mills 32 and 33 from the process computer 11. The cold rolling conditions from the process computer 11 include, for example, the steel type, size, reduction ratio Pr, rolling cycle, and the like of the steel plate 15 after the rust prevention treatment that is cold rolled by the cold rolling mills 32 and 33. . Based on the cold rolling conditions acquired from the process computer 11, the control unit 10 determines the reduction ratio Pr of the steel plate 15 by the cold rolling mills 32 and 33, and the steel plates after the cold rolling mills 32 and 33 have rust-proofed. Recognize 15 before cold rolling. The control unit 10 applies the amount of rust preventive oil to be applied to the surface of the steel plate 15 according to the rolling reduction Pr when the steel plate 15 after the rust prevention treatment is cold-rolled by the cold rolling mills 32 and 33. Qa is set, and the rust preventive processing unit 2 is controlled so that the surface of the steel plate 15 is coated with the rust preventive oil having the set oil amount Qa. In this case, the control unit 10 reads the necessary oil amount information 9a that meets the cold rolling conditions from the process computer 11 from the storage unit 9, and after the rust prevention treatment based on the read necessary oil amount information 9a. Required amount Qb of the rust preventive oil corresponding to the rolling reduction Pr of the steel plate 15 is derived. The control unit 10 controls the rust prevention processing unit 2 so that the surface of the steel plate 15 is coated with the rust preventive oil of the derived necessary oil amount Qb or more. That is, the control part 10 controls the oil application quantity Qa of the antirust oil which the antirust process part 2 applies to the surface of the steel plate 15 to more than the required oil application quantity Qb.

  On the other hand, the process computer 11 is necessary for satisfying the order information indicating the steel type and size required for the steel plate product in the production line of the steel plate product such as the rolling line 20 and the DR rolling line 30 and the order information. Maintain and manage manufacturing conditions such as cold rolling conditions. In the present embodiment, the process computer 11 informs the control unit 10 of the cold rolling conditions of the cold rolling mills 32 and 33 for the steel plate 15 at a timing before the rust prevention treatment is performed on the steel plate 15. provide. The process computer 11 sequentially performs such cold rolling condition provision processing for the control unit 10 for each steel plate product.

(Amount of rust preventive oil applied)
Next, the oil application amount Qa of the rust preventive oil to be applied to the surface of the cold rolled steel sheet 15 will be described. In the present embodiment, the amount Qa of the rust preventive oil applied to the steel plate 15 is controlled according to the rolling reduction Pr during the cold rolling of the steel plate 15 performed after the steel plate 15 is subjected to the rust prevention treatment. More specifically, the required oil application amount Qb of the rust preventive oil is derived according to the reduction ratio Pr of the steel sheet 15, and the oil application amount Qa of the rust preventive oil is controlled to be equal to or greater than the required oil application amount Qb. . Here, the required amount Qb of rust-preventing oil is supplied to the water-soluble lubricant 12 to a roll bite (hereinafter referred to as a cold-rolled roll bite as appropriate) when cold-rolling the steel plate 15 after the antirust treatment. This is the minimum amount of rust preventive oil required to obtain the same level of lubricity as that of the emulsion rolling oil.

  The lubrication apparatus 1 according to the present embodiment includes the required oil amount information 9a indicating the correlation between the required oil amount Qb of the rust preventive oil for the steel plate 15 and the reduction ratio Pr by cold rolling of the steel plate 15 after the antirust treatment. Is stored in the storage unit 9 (see FIG. 1), and the oil amount Qa of the rust preventive oil is controlled using the necessary oil amount information 9a as described above. Such necessary oil amount information 9a is the operation result data of the conventional cold rolling process that supplies emulsion rolling oil to the cold rolling roll bite of the steel sheet 15 that has not been subjected to rust prevention treatment and imparts lubricity, It is set using experimental data of a cold rolling process in which the water-soluble lubricant 12 is supplied to the cold rolling roll bite of the steel plate 15 after the rust prevention treatment to impart lubricity. For example, the rust preventive oil having the same level of lubricity of the cold rolling roll bite caused by the emulsion rolling oil and the lubricity of the cold rolling roll bite caused by the water-soluble lubricant 12 and the rust preventive oil based on the above operational performance data The oil amount range is derived for each rolling reduction Pr, steel type, size, and rolling cycle of the steel plate 15 based on the experimental data. The required amount Qb of the rust preventive oil for the steel plate 15 is set as the lower limit of the oil amount range derived as described above, and the required amount Qb of the rust preventive oil for the steel plate 15 and the steel plate after the rust preventive treatment are used. The correlation with the reduction ratio Pr of 15 is set for each steel type, size, and rolling cycle of the steel plate 15.

  FIG. 2 is a diagram showing an example of the correlation between the required amount of rust preventive oil applied to the steel sheet and the reduction ratio in cold rolling of the steel sheet after the rust prevention treatment. In the present embodiment, the required oil amount information 9a indicating the correlation between the required oil amount Qb of the rust preventive oil as exemplified in FIG. 2 and the rolling reduction Pr of the steel plate 15 after the rust preventive treatment is used. The amount Qa of rust preventive oil to be applied to the surface of the steel plate 15 is controlled. For example, as shown in FIG. 2, the required amount Qb of the rust preventive oil increases stepwise as the rolling reduction Pr of the steel plate 15 after the rust preventive treatment increases. The coating amount Qa of the rust preventive oil to the steel plate 15 is a facility such as a change in the required oil amount Qb according to the rolling reduction Pr and a variation in the coating amount of the rust preventive oil by the rust preventive processing unit 2 described above. In consideration of the ability, the control is performed so as to ensure a required oil amount Qb or more corresponding to the rolling reduction Pr of the steel plate 15 after the rust prevention treatment.

Further, the amount Qa of the rust preventive oil applied to the steel plate 15 satisfies the above-described condition of the required amount Qb or more, and is within the range of 10 [mg / m ² ] or more and 150 [mg / m ² ] or less. It is desirable to satisfy the condition that This is due to the following reason. That is, when the coating amount Qa of the rust preventive oil is less than 10 [mg / m ² ], the adhesion amount of the rust preventive oil on the surface of the steel plate 15 after the rust preventive treatment is too small. The rust preventive oil does not contribute sufficiently to imparting lubricity to the hot rolling roll bite. As a result, it becomes difficult to ensure the lubricity of the cold-rolled roll bite to the same degree as that of the emulsion rolling oil for the steel plate 15 after the rust prevention treatment. On the other hand, when the coating amount Qa of the rust preventive oil exceeds 150 [mg / m ² ], the adhesion amount of the rust preventive oil on the surface of the steel plate 15 after the rust preventive treatment is too large. Slip is likely to occur between the transporting roll and the steel plate 15. As a result, there is a possibility that the conveyance of the steel plate 15 may be hindered.

(Lubrication method)
Next, a lubrication method according to an embodiment of the present invention will be described. FIG. 3 is a flowchart showing an example of the lubrication method according to the embodiment of the present invention. The lubrication method according to the present embodiment is lubricated between the rolling rolls 32a, 32b, 33a, 33b of the cold rolling mills 32, 33 and the steel sheet 15 to be cold rolled using the lubrication apparatus 1 shown in FIG. This is a lubrication method that imparts properties, and sequentially performs steps S101 to S104 shown in FIG. Hereinafter, the lubrication method according to the present embodiment will be described in detail with reference to FIGS.

  In the lubrication method according to the present embodiment, as shown in FIG. 3, the lubrication apparatus 1 first obtains the cold rolling conditions of the steel sheet 15 to be cold rolled (step S101). In step S <b> 101, the control unit 10 acquires from the process computer 11 the cold rolling conditions of the steel sheet 15 by the cold rolling mills 32 and 33 in the DR rolling line 30. Specifically, the control unit 10 includes, as the cold rolling conditions for the steel plate 15, the steel type of the steel plate 15, the plate widths and thicknesses of the steel plate 15 before and after the cold rolling, and the cold of the steel plate 15 after the rust prevention treatment. The reduction ratio Pr by rolling is acquired.

Subsequently, the lubrication apparatus 1 sets the oil application amount Qa of the rust preventive oil to the steel plate 15 according to the rolling reduction Pr by the cold rolling of the steel plate 15 (step S102). In step S102, the control unit 10 cold-rolls the rolling reduction ratio among the cold rolling conditions acquired from the process computer 11 as the rolling reduction ratio Pr when the steel sheet 15 is cold-rolled by the cold rolling mills 32 and 33. Recognize before. Next, the control unit 10 sets the oil application amount Qa of the rust preventive oil to the steel plate 15 according to the recognized reduction rate Pr. In this case, the control unit 10 reads the necessary oil amount information 9a that matches the cold rolling conditions acquired from the process computer 11 from the storage unit 9, and based on the read necessary oil amount information 9a, the rust prevention treatment is performed. The required oil amount Qb of the rust preventive oil corresponding to the rolling reduction Pr of the subsequent steel plate 15 is derived. Here, the necessary oil amount information 9a is the water-soluble lubricant 12 between the rolling rolls 32a, 32b, 33a, 33b of the cold rolling mills 32, 33 and the steel plate 15 after the antirust treatment, as described above. Required amount Qb of rust preventive oil required to obtain the same level of lubricity as emulsion rolled oil, and reduction ratio Pr by cold rolling mills 32 and 33 of steel plate 15 after rust prevention treatment Information indicating the correlation. In the required oil amount information 9a, the required oil amount Qb of the rust preventive oil for the steel plate 15 is gradually increased as the rolling reduction Pr of the steel plate 15 after the rust preventive treatment increases, as shown in FIG. To increase. Based on the correlation between the required oil amount Qb and the reduction rate Pr indicated in the required oil amount information 9a, the control unit 10 requires the required oil amount Qb corresponding to the reduction rate Pr from the process computer 11. Is derived. Next, the control unit 10 considers the required oil amount Qb corresponding to the reduction ratio Pr and the equipment capacity (oil amount variation, etc.) of the rust preventive processing unit 2, and the oil amount Qa of the rust preventive oil Is set to the required amount of oil Qb or more. For example, when the rolling reduction rate Pr is 10 [%], the control unit 10 performs the rust prevention processing unit 2 for the required oil amount Qb (= 30 [mg / m ² ]) corresponding to the rolling reduction rate Pr. The oil supply amount Qa (≧ 30 [mg / m ² ]) equal to or greater than the necessary oil amount Qb is set by adding the surplus oil amount equal to or greater than the oil amount variation. In addition, when setting the oil amount Qa, the control unit 10 sets the lower limit of the oil amount Qa to 10 [mg / m ² ] and the upper limit of the oil amount Qa to 150 [mg / m ² ]. That is, the control unit 10 sets the oil amount Qa that is not less than the required oil amount Qb corresponding to the rolling reduction Pr and is in the range of 10 [mg / m ² ] to 150 [mg / m ² ], The amount of rust preventive oil to be applied to the steel plate 15 is set.

Next, the lubrication apparatus 1 applies the rust preventive oil of the oil application amount Qa set in step S102 to the surface of the steel plate 15 and rust-proofs the steel plate 15 (step S103). In step S <b> 103, the lubricating device 1 applies the rust preventive oil to the surface of the steel plate 15 while controlling the oil application amount Qa of the rust preventive oil to be equal to or greater than the required oil apply amount Qb. In detail, the control part 10 controls the rust prevention process part 2 so that the rust preventive oil of the oil application quantity Qa set according to the rolling reduction Pr as mentioned above may be applied to the surface of the steel plate 15. Based on the control of the control unit 10, the rust prevention processing unit 2 has a condition that the required oil amount Qb or more according to the reduction rate Pr and 10 [mg / m ² ] or more and 150 [mg / m ² ] or less. The surface of the steel plate 15 is coated with a rust preventive oil having an oil coating amount Qa that satisfies the condition of being within the above range. In addition, the kinematic viscosity at 40 [° C.] of the rust preventive oil applied to the surface of the steel plate 15 by the rust preventive portion 2 is, for example, less than 15 [mm ² / s]. In the present embodiment, the rust prevention treatment unit 2 sequentially performs the above-described rust preventive oil application treatment of the oil application amount Qa on the steel plate 15 being continuously annealed by the continuous annealing equipment 21. Thereby, the rust prevention process part 2 carries out the rust prevention process over the surface whole surface of the steel plate 15 after continuous annealing.

  Thereafter, the lubrication apparatus 1 is a water-soluble solution having no cloud point below the temperature of the interface between the steel plate 15 after the rust prevention treatment and the rolling rolls 32a, 32b, 33a, 33b of the cold rolling mills 32, 33. The reactive lubricant 12 is supplied (step S104).

  In step S <b> 104, the steel plate 15 after the rust prevention treatment is wound into a coil shape by the winding device 22 of the rolling line 20, resulting in the coil 16. The coil 16 is attached to the payoff reel 31 of the DR rolling line 30 at a desired timing. The payoff reel 31 sequentially pays out the rust-proof steel plate 15 from the coil 16 toward the cold rolling mill 32 of the DR rolling line 30. The rust-proof steel plate 15 paid out from the payoff reel 31 reaches the entry side of the cold rolling mill 32 via the entry side bridle roll 35 and is rolled by the rolling rolls 32 a and 32 b of the cold rolling mill 32. Sequentially cold rolled.

  The lubricant supply units 6a and 6b receive the water-soluble lubricant 12 received from the lubricant tank 3 through the branch pipe 4a and the like, and the interface between the rolling rolls 32a and 32b of the cold rolling mill 32 and the steel plate 15 after the rust prevention treatment. Supply to the jet. Here, the water-soluble lubricant 12 is a lubricant that does not have a cloud point below the temperature at the interface between the rolling rolls 32a and 32b that rise in temperature due to processing heat generation and frictional heat generation in cold rolling and the steel plate 15 after the rust prevention treatment. It is an agent. Further, the water-soluble lubricant 12 contains a fatty acid having a carbon chain number larger than the carbon chain number of the oil component of the rust preventive oil applied to the steel plate 15. The lubricant supply units 6a and 6b are thus sprayed with the water-soluble lubricant 12 having no cloud point and containing a fatty acid on the interface between the rolling rolls 32a and 32b and the steel plate 15 after the rust prevention treatment. This water-soluble lubricant 12 is supplied to the cold rolling roll bite of the steel plate 15 after the rust prevention treatment. The lubrication apparatus 1 includes a water-soluble lubricant 12 supplied to the cold rolling roll bite of the steel plate 15 after the antirust treatment from the lubricant supply units 6a and 6b, and a rust preventive oil attached to the surface of the steel plate 15. It combines in this cold rolling roll bite. Thereby, the lubrication apparatus 1 provides lubricity comparable to emulsion rolling oil between the rolling rolls 32a and 32b of the cold rolling mill 32 and the steel sheet 15 to be cold rolled.

  On the other hand, in step S104, the steel plate 15 after the rust prevention treatment is cold-rolled by the cold rolling mill 32, and then cooled from the exit side of the cold rolling mill 32 through the air injection region by the air injection unit 8a. It reaches the entry side of the rolling mill 33. In that case, the air injection part 8a injects air on the upper surface of the steel plate 15 which reached this air injection area | region, and, thereby, removes the water-soluble lubricant 12 from the upper surface of this steel plate 15. After the cold-rolled steel plate 15 (hereinafter referred to as a rust-proof and cold-rolled steel plate) 15 is removed from the water-soluble lubricant 12 in this way, the rolling roll of the cold rolling mill 33 is used. Cold rolling is performed sequentially by 33a and 33b.

  The lubricant supply units 6c and 6d receive the water-soluble lubricant 12 received from the lubricant tank 3 through the branch pipe 4c and the like, the rolling rolls 33a and 33b of the cold rolling mill 33, and the steel plate 15 after rust prevention and cold rolling. The spray is supplied to the interface. Here, the water-soluble lubricant 12 has a cloud point below the temperature of the interface between the rolling rolls 33a and 33b and the steel plate 15 after rust prevention and cold rolling, as in the case of the cold rolling mill 32 described above. Absent. Moreover, the water-soluble lubricant 12 contains a fatty acid having a carbon chain number larger than the carbon chain number of the oil component of the rust preventive oil as described above. The lubricant supply units 6c and 6d thus spray the water-soluble lubricant 12 having no cloud point and containing a fatty acid onto the interface between the rolling rolls 33a and 33b and the steel plate 15 after rust prevention and cold rolling. Thus, the water-soluble lubricant 12 is supplied to the cold rolling roll bite of the steel plate 15 after rust prevention and cold rolling. The lubricating device 1 includes a water-soluble lubricant 12 supplied to the cold rolling roll bite of the steel plate 15 after rust prevention and cold rolling from the lubricant supply units 6c and 6d, and a rust preventive oil adhering to the surface of the steel plate 15; Are combined in this cold rolling roll bite. Thereby, the lubrication apparatus 1 provides lubricity comparable to emulsion rolling oil between the rolling rolls 33a and 33b of the cold rolling mill 33 and the steel sheet 15 to be cold rolled.

  A steel plate 15 (hereinafter referred to as a steel plate after DR rolling) 15 after being cold-rolled by the cold rolling mill 33 exits from the exit side of the cold rolling mill 33 via an air injection region by the air injection unit 8b. The entrance side of the bridle roll 36 is sequentially reached. In that case, the air injection part 8b injects air on the upper surface of the steel plate 15 after DR rolling that has reached the air injection region, thereby removing the water-soluble lubricant 12 from the upper surface of the steel plate 15 after DR rolling. To do. After the DR rolling, the steel plate 15 is sequentially removed from the water-soluble lubricant 12 and then reaches the tension reel 37 via the outlet bridle roll 36 and is wound into a coil by the tension reel 37. Coil 17. Thereafter, the coil 17 is shipped as a product, or is subjected to another process as necessary.

  On the other hand, in step S104, the cooling sprays 7a and 7b inject the water-soluble lubricant 12 received from the lubricant tank 3 through the branch pipes 4b and the like onto the backup rolls of the cold rolling mill 32. Thereby, the cooling sprays 7 a and 7 b cool the backup rolls and the rolling rolls 32 a and 32 b of the cold rolling mill 32 to a temperature suitable for cold rolling of the steel plate 15.

  In addition, whenever the steel plate 15 of cold rolling object is conveyed, the lubrication apparatus 1 performs each process of step S101-S104 mentioned above with respect to this steel plate 15 sequentially. Thereby, the lubrication apparatus 1 ensures the lubricity comparable to emulsion rolling oil in the cold rolling roll bite of the steel plate 15 conveyed sequentially, and prevents the occurrence of motoring on the surface of the steel plate 15.

(Examples and Comparative Examples)
Next, examples and comparative examples for specifically explaining the effects of the present invention will be described. In this embodiment, the continuous annealing equipment 21 of the rolling line 20 shown in FIG. 1, the cold rolling machines 32 and 33 of the DR rolling line 30, the lubrication apparatus 1, and the like are used to cold-roll the steel sheet 15 to be cold rolled. Rolled.

  Specifically, the steel plate 15 is continuously annealed by the continuous annealing equipment 21, and then the rust preventive oil 2 is applied to the surface of the steel plate 15 after the continuous annealing by the rust preventive treatment part 2 of the lubricating device 1, thereby The steel plate 15 after the continuous annealing was subjected to rust prevention treatment. In this rust prevention treatment, the rust prevention treatment part 2 applied rust prevention oil mainly composed of dioctyl sebacate (carbon chain number = 10) to the surface of the steel plate 15 after continuous annealing by an electrostatic method. On the other hand, the cold rolling mill 32 in the first stand among the two cold rolling mills 32 and 33 in the DR rolling line 30 has a rolling reduction Pr of 15 to 30 with respect to the steel plate 15 after the rust prevention treatment. Cold rolling was sequentially performed while changing to [%]. The cold rolling mill 33 at the second stand sequentially performs light rolling cold rolling with a rolling reduction Pr of less than 1% on the steel sheet 15 after the cold rolling by the cold rolling machine 32, Thereby, the surface roughness of the steel plate 15 was adjusted. In addition, 600 [m / min] was set as the target speed for the sheet passing speed of the steel sheet 15 during the cold rolling by the cold rolling mills 32 and 33.

  In addition, when the cold rolling mill 32 cold-rolls the steel plate 15 after the rust prevention treatment, the lubricating device 1 is connected to the rolling rolls 32a and 32b of the cold rolling mill 32 and the rust prevention treatment from the lubricant supply units 6a and 6b. The water-soluble lubricant 12 was supplied to the interface with the subsequent steel plate 15. Similarly, when the cold rolling mill 33 cold-rolls the steel plate 15 after rust prevention and cold rolling, the lubricating device 1 starts from the lubricant supply units 6c and 6d to the rolling rolls 33a and 6b of the cold rolling mill 33. The water-soluble lubricant 12 was supplied to the interface between 33b and the steel plate 15 after rust prevention and cold rolling. The water-soluble lubricant 12 is a lubricant that does not have a cloud point below the temperature of the roll tool of the steel plate 15 in the cold rolling mills 32 and 33. In the present embodiment, such a water-soluble lubricant 12 is diluted by mixing a water-soluble lubricant stock solution with dilution water in the lubricant tank 3, whereby the concentration is 5 [mass%] and the temperature. Was a lubricant having a temperature of 30 [° C.]. In addition, the water-soluble lubricant 12 was obtained by adding 5% by mass of a fatty acid having a carbon chain number (= 12) larger than the above-described rust preventive oil having a carbon chain number = 10.

In the present embodiment, a tin plate having a base material thickness of 0.23 [mm] and a plate width of 900 [mm] is used as the steel plate 15 to be cold-rolled. The steel sheet 15 after the rust prevention treatment was successively cold-rolled while controlling the amount Qa of the rust-prevention oil in response to the reduction rate Pr by the cold rolling mill 32. Here, the coating amount Qa of the rust-preventing oil is 10 [mg / m ² ] or more and 150 [mg / m ² ] or less under the condition that the necessary coating amount Qb or more of the rust-preventing oil according to the reduction ratio Pr. It was controlled so that both conditions were satisfied. For example, in this embodiment, it is assumed that the required amount Qb of rust preventive oil applied to the steel plate 15 and the reduction rate Pr of the steel plate 15 after the rust preventive treatment have a correlation as shown in FIG. In this case, if the rolling reduction rate Pr is 15 [%], the required coating amount Qb corresponding to the rolling reduction Pr of 15 [%] is 30 [mg / m ² ]. As mentioned above, it controls to 150 [mg / m < ² >] or less. If the reduction rate Pr is 20 to 25 [%], the oil application amount Qa of the rust preventive oil is the required oil application amount Qb corresponding to the reduction rate Pr of 20 to 25 [%] = 50 [mg / m ² ]. As mentioned above, it controls to 150 [mg / m < ² >] or less. If the reduction rate Pr is 30 [%], the oil application amount Qa of the rust preventive oil is the required oil application amount Qb = 80 [mg / m ² ] or more according to the reduction rate Pr of 30 [%], 150 [ mg / m ² ] or less.

As described above, the rolling line load of the cold rolling mill 32 is measured for each rolling reduction Pr while controlling the coating amount Qa of the rust preventive oil to the steel sheet 15 according to the rolling reduction Pr, and the rolling wire for each rolling reduction Pr. Using the measured value of the load, the lubricity of the roll bite between the cold rolling mill 32 and the steel plate 15 in this example was evaluated. On the other hand, in the comparative example with respect to the present embodiment, the oil coating amount Qa is not adjusted according to the rolling reduction Pr, and the surface of the steel plate 15 has a constant oil coating amount (= 30 [mg / m ² ]). The other conditions were the same as in this example. Also for this comparative example, the rolling line load of the cold rolling mill 32 is measured for each rolling reduction Pr, and the roll bite of the cold rolling mill 32 and the steel plate 15 is measured using the measured value of the rolling line load for each rolling reduction Pr. The lubricity was evaluated. Table 1 shows the results of the lubricity evaluation of these examples and comparative examples.

  In Table 1, the mark “◯” indicates comparison between the actual value of the rolling line load at the time of supplying the rolling oil in the cold rolling mill 32 and the measured value of the rolling line load for each rolling reduction Pr in the example or the comparative example. As a result, it is shown that the measured value of the rolling line load for each rolling reduction Pr was not more than the actual value of the rolling line load at the time of supplying the rolling oil. That is, the mark “◯” indicates that the lubricity of the roll bite between the cold rolling mill 32 and the steel plate 15 after the rust prevention treatment is as good as or better than the lubricity of the roll bite caused by the emulsion rolling oil. Means. On the other hand, the “x” mark indicates the result of comparing the actual value of the rolling line load at the time of supplying the rolling oil in the cold rolling mill 32 and the measured value of the rolling line load according to the rolling rate Pr. It shows that the measured value of the rolling line load exceeded the actual value of the rolling line load when the rolling oil was supplied. That is, the “×” mark is difficult to roll because the lubricity of the roll bite between the cold rolling mill 32 and the steel plate 15 after the rust prevention treatment is inferior to the lubricity of the roll bite caused by the emulsion rolling oil. Means that. In addition, the rolling line load at the time of rolling oil supply is the rolling of the cold rolling mill 32 obtained when cold rolling the steel plate 15 while supplying emulsion rolling oil to the roll bite of the cold rolling mill 32 and the steel plate 15. It is a line load. Moreover, the lubricity of the roll bite resulting from the emulsion rolling oil is the lubricity of the roll bite of the steel plate 15 obtained when the emulsion rolling oil is supplied to the roll bite of the steel plate 15.

  As shown in Table 1, in this example, the cold rolling mill 32 and the rolling reduction Pr are any of 15 [%], 20 [%], 25 [%], and 30 [%]. The lubricity of the roll bite with the steel plate 15 after the rust prevention treatment could be maintained at the same level or more as the lubricity of the roll bite resulting from the emulsion rolling oil. That is, while ensuring the lubricity equal to or higher than the lubricity of the roll bite caused by the emulsion rolling oil in the roll bite between the cold rolling mill 32 and the steel plate 15 after the rust prevention treatment, The rate of cold rolling could be performed. This is because the rust preventive oil and the water-soluble lubricant 12 are mixed in the roll bite of the steel plate 15 by attaching the rust preventive oil of the required oil amount Qb or more according to the rolling reduction Pr to the surface of the steel plate 15. This is because the lubricating action of the water-soluble lubricant 12 exerted on the roll bite of the steel plate 15 is enhanced by the rust preventive oil. Furthermore, in this embodiment, since a fatty acid having a carbon chain number larger than that of the rust preventive oil is added to the water-soluble lubricant 12, the rust preventive oil on the surface of the steel plate 15 and the water-soluble lubricant 12 By the combination, the improvement of the lubricity of the roll bite of the steel plate 15 could be promoted. The reason why the lubricity of the roll bite of the steel sheet 15 is improved by increasing the number of carbon chains of the fatty acid contained in the water-soluble lubricant 12 is, for example, that the carbon chain of this fatty acid becomes long, It is conceivable that metal contact (for example, contact between the steel plate 15 and the rolling rolls 32a and 32b) can be suppressed. Alternatively, it is considered as one of the reasons that fatty acid and rust preventive oil are regularly arranged by roll bites of the steel plate 15 to form a strong lubricating film by chain matching theory.

  Further, although not particularly shown in Table 1, in this example, no motoring was always generated on the surface of the steel plate 15 regardless of the rolling reduction Pr. This is because the water-soluble lubricant 12 having no cloud point below the temperature of the roll bite is supplied to the roll bite of the cold rolling mill 32 and the steel plate 15 after the rust prevention treatment, and the roll bite is lubricated. It is because the nature was given. That is, by supplying the water-soluble lubricant 12 having no cloud point to the roll bite of the steel plate 15 after the rust prevention treatment, the water-soluble lubricant 12 in the roll bite aggregates and coarsens the lubricating component. Without making it, it contributes to the improvement of the lubricity between the rolling rolls 32a and 32b of the cold rolling mill 32 and the steel plate 15.

  On the other hand, in the comparative example, as shown in Table 1, when the rolling reduction Pr is 20 [%], 25 [%], and 30 [%], the cold rolling mill 32 and the steel plate 15 after the antirust treatment are used. The lubricity of the roll bite was inferior to the lubricity of the roll bite resulting from the emulsion rolling oil. This is because the amount Qa of the rust preventive oil to be applied to the surface of the steel plate 15 is less than the required amount Qb corresponding to the rolling reduction Pr, and as a result, the rust preventive oil against the lubricating action of the water-soluble lubricant 12 This is because of the lack of contribution.

  As described above, in the embodiment of the present invention, the amount of rust preventive oil applied to the cold-rolled steel sheet is set according to the reduction rate when the steel sheet is cold-rolled by a cold rolling mill. Set and apply the set amount of rust preventive oil to the surface of the steel sheet to be cold-rolled, anti-rust the steel sheet, and the steel roll after the anti-rust treatment and the rolling roll of the cold rolling mill. The water-soluble lubricant that does not have a cloud point below the temperature of this interface is supplied to the interface, and lubricity is imparted between the rolling roll of the cold rolling mill and the steel plate after the rust prevention treatment. Yes.

  For this reason, in a roll bite between a cold rolling mill and a steel plate after rust prevention treatment, an appropriate amount of rust preventive oil with a coating amount corresponding to the reduction ratio and a water-soluble lubricant without clouding point is combined appropriately. The rust preventive oil can enhance the lubricating action of the water-soluble lubricant on the roll bite without agglomerating and coarsening the lubricating component of the basic lubricant. As a result, the lubricity of the roll bite between the cold rolling mill and the steel sheet after the anticorrosion treatment can always be maintained at the same level or higher as the roll bite lubricity caused by the emulsion rolling oil regardless of the rolling reduction ratio of the steel plate. At the same time, it is possible to avoid the occurrence of oil pits that can cause motoring on the surface of the steel sheet. As a result, it is possible to prevent the occurrence of motoring on the surface of the steel sheet after the cold rolling while ensuring the lubricity of the roll tool necessary for the cold rolling of the steel sheet.

  By using the lubrication apparatus and the lubrication method according to the present invention, while maintaining the same level of lubricity as that of the supply of emulsion rolling oil in the roll bite of the steel sheet to be cold rolled, Hot rolling can be performed. Furthermore, it is possible to stably manufacture a cold-rolled steel sheet having a good appearance and no mottling. In particular, by applying the lubrication apparatus and the lubrication method according to the present invention to the DR rolling method, it is possible to stably produce cold-rolled steel sheets that require a high-quality appearance such as food can raw materials by DR rolling. .

  Moreover, in the embodiment of the present invention, a fatty acid having a carbon chain number larger than the carbon chain number of the oil component of the rust preventive oil to be applied to the steel sheet surface to be cold-rolled is added to the water-soluble lubricant, A water-soluble lubricant containing this fatty acid and having no cloud point is supplied to the interface between the rust-proof steel plate and the rolling roll of the cold rolling mill. Thereby, in the roll bite of a cold rolling mill and the steel plate after an antirust process, the antirust oil on the surface of this steel plate and the fatty acid in this water-soluble lubricant can be combined. As a result, the lubrication effect of the water-soluble lubricant on the roll bite of the steel sheet to be cold rolled can be further improved by the synergistic effect of the rust preventive oil and the fatty acid, thereby further promoting the improvement of the lubricity of the roll bite. Can do.

  In the above-described embodiment, the water-soluble lubricant 12 supplied to the roll bite of the steel plate 15 is removed from the surface of the steel plate 15 by air injection after the cold rolling of the steel plate 15. It is not limited. In addition, a recovery container that receives the water-soluble lubricant 12 removed from the upper surface of the steel plate 15 by the air injection units 8a and 8b and the water-soluble lubricant 12 that has dropped from the lower surface of the steel plate 15, and the recovery container to the lubricant tank 3 Alternatively, a circulation pipe for circulating the used water-soluble lubricant 12 may be provided in the lubrication apparatus 1 so that the water-soluble lubricant 12 can be circulated and recovered.

  Moreover, in embodiment mentioned above, although the rust prevention process part 2 of the lubrication apparatus 1 was integrated in the continuous annealing equipment 21 of the rolling line 20, this invention is not limited to this. Specifically, the rust prevention treatment unit 2 may be installed independently in the rolling line 20 (for example, the next step of the continuous annealing equipment 21 or the like) without being incorporated in the continuous annealing equipment 21, It may be installed between the payoff reel 31 and the cold rolling mill 32. That is, the rust prevention processing unit 2 is set in the preceding stage of the target cold rolling mill such as the cold rolling mill 32 that performs the cold rolling of the second stage of the DR rolling method. May be supplied to the roll bite of the steel plate 15 after the antirust treatment.

  Furthermore, in embodiment mentioned above, the rolling line 20 which performs each process, such as a hot rolling, cold rolling, and continuous annealing, sequentially with respect to the steel plate 15, and the 2nd step in DR rolling with respect to the steel plate 15 are carried out. Although the DR rolling line 30 that performs cold rolling is a discontinuous line, the present invention is not limited to this. That is, in the present invention, the rolling line 20 and the DR rolling line 30 may be configured as a continuous line. In this case, without providing the winding device 22 and the payoff reel 31, etc., the conveying path of the steel plate 15 from the continuous annealing equipment 21 to the cold rolling mill 32 of the DR rolling equipment 34 is set as a continuous conveying path, and the continuous annealing is performed. The steel plate 15 after the rust prevention treatment may be continuously conveyed from the exit side of the continuous annealing equipment 21 toward the entrance side of the cold rolling mill 32.

  In the embodiment described above, the DR rolling equipment 34 to which the lubrication apparatus 1 is applied is configured by the cold rolling mills 32 and 33 of all two stands, and each of the cold rolling mills 32 and 33 is Although the four-stage cold rolling mill has four rolls (a backup roll and a rolling roll), the present invention is not limited to this. That is, the DR rolling equipment 34 may be configured by a cold rolling mill having a desired number of stands and roll stages, and in the present invention, the number of stands and roll stages in the cold rolling mill are not particularly limited.

  Furthermore, in embodiment mentioned above, although the lubrication apparatus 1 was applied to DR rolling equipment 34 (mainly cold rolling mill 32) which performs the cold rolling of the 2nd step in DR rolling method, the present invention, It is not limited to this. That is, the lubricating device 1 and the lubricating method according to the present invention can be applied to a cold rolling mill other than the DR rolling method.

  Moreover, in embodiment mentioned above, although the steel plate was illustrated as a metal plate of cold rolling object, it is not restricted to this, Lubricity is provided to a roll bite with the lubrication apparatus 1 and the lubrication method concerning this invention. The metal plate to be cold-rolled may be an iron alloy other than steel, or may be other than an iron alloy such as copper or aluminum. That is, in the present invention, the metal plate to be cold-rolled may be a steel plate, an iron alloy plate other than the steel plate, or a metal plate other than the iron alloy plate, and the type of metal plate such as a steel type (for example, The strength and composition are not particularly limited.

  Furthermore, in the above-described embodiment, the required oil application amount Qb of the rust preventive oil to the steel plate 15 increases stepwise as the rolling reduction Pr of the steel plate 15 after the rust prevention treatment increases. However, the present invention is not limited to this. That is, the correlation between the reduction ratio Pr of the steel plate 15 and the required oil amount Qb of the rust preventive oil in the present invention is such that the required oil amount Qb increases linearly (simply increases) as the reduction rate Pr increases. Alternatively, the reduction ratio Pr and the required oil amount Qb may be associated with each other so as to follow a curve based on a quadratic or higher-order functional expression.

  Further, the present invention is not limited by the above-described embodiment, and the present invention includes a configuration in which the above-described constituent elements are appropriately combined. In addition, all other embodiments, examples, operation techniques, and the like made by those skilled in the art based on the above-described embodiments are included in the present invention.

DESCRIPTION OF SYMBOLS 1 Lubricator 2 Rust prevention processing part 3 Lubricant tank 4 Supply piping 4a, 4b, 4c Branch pipe 5 Pump 6a, 6b, 6c, 6d Lubricant supply part 7a, 7b Cooling spray 8a, 8b Air injection part 9 Memory | storage part 9a Required oil amount information 10 Control unit 11 Process computer 12 Water-soluble lubricant 15 Steel plate 16, 17 Coil 20 Rolling line 21 Continuous annealing equipment 22 Winding device 30 DR rolling line 31 Payoff reel 32, 33 Cold rolling mill 34 DR rolling Equipment 35 Incoming bridle roll 36 Outgoing bridle roll 37 Tension reel

Claims (10)

In a lubricating device that imparts lubricity between a rolling roll of a cold rolling mill that cold-rolls a metal plate and the metal plate to be cold-rolled,
A rust preventive treatment part for applying a rust preventive oil to the surface of the metal plate to rust prevent the metal plate;
Water-soluble lubrication that does not have a cloud point below the temperature of the interface at the interface between the rolling roll of the cold rolling mill for cold rolling the metal plate after the antirust treatment and the metal plate after the antirust treatment A lubricant supply section for supplying the agent;
In accordance with the reduction ratio when cold rolling the metal plate after the rust prevention treatment by the cold rolling mill, the oil application amount of the rust prevention oil is set, and the rust prevention oil of the set oil application amount is set. A control unit for controlling the rust prevention treatment unit so as to oil the surface of the metal plate,
A lubrication apparatus comprising:   2. The lubricating device according to claim 1, wherein the water-soluble lubricant contains a fatty acid having a carbon chain number larger than the carbon chain number of the oil component of the rust preventive oil. Necessity of the rust preventive oil required to obtain the same level of lubricity as emulsion rolling oil when the water soluble lubricant is supplied between the rolling roll of the cold rolling mill and the metal plate after the rust preventive treatment A storage unit for storing required oil amount information indicating a correlation between an oil amount and a reduction ratio of the metal plate after the rust prevention treatment by the cold rolling mill;
The control unit derives the required oil amount of the rust preventive oil according to the reduction ratio of the metal plate after the antirust treatment based on the required oil amount information, and derives the required oil amount The lubrication apparatus according to claim 1 or 2, wherein the rust prevention treatment part is controlled so as to apply the rust prevention oil to the surface of the metal plate. The lubrication apparatus according to claim 3, wherein an amount of the rust preventive oil applied to the metal plate is 10 [mg / m ² ] or more and 150 [mg / m ² ] or less. The lubrication apparatus according to claim 1, wherein the rust preventive oil has a kinematic viscosity at 40 ° C. of less than 15 mm ² / s. In a lubrication method for imparting lubricity between a rolling roll of a cold rolling mill for cold rolling a metal plate and the metal plate to be cold rolled,
According to the rolling reduction when the metal plate is cold-rolled by the cold rolling mill, an oil amount setting step for setting an oil amount of rust preventive oil for the metal plate,
A rust preventive treatment step for applying a rust preventive treatment to the surface of the metal plate by applying the rust preventive oil of the set oil amount to the surface of the metal plate;
Water-soluble lubrication that does not have a cloud point below the temperature of the interface at the interface between the rolling roll of the cold rolling mill for cold rolling the metal plate after the antirust treatment and the metal plate after the antirust treatment A lubricant supply step for supplying an agent;
A lubrication method comprising:   The lubricating method according to claim 6, wherein the water-soluble lubricant contains a fatty acid having a carbon chain number larger than the carbon chain number of the oil component of the rust preventive oil. The oil application amount setting step obtains the same level of lubricity as emulsion rolling oil when the water-soluble lubricant is supplied between the rolling roll of the cold rolling mill and the metal plate after the antirust treatment. Based on the required oil amount information indicating the correlation between the required oil amount of the rust preventive oil required for reduction and the reduction ratio of the metal plate after the rust preventive treatment by the cold rolling mill, Deriving the required coating amount of the rust-preventing oil according to the rolling reduction of the metal plate, setting the coating amount of the rust-preventing oil to be more than the required coating amount,
The rust prevention treatment step comprises applying the rust prevention oil to the surface of the metal plate while controlling the amount of the rust prevention oil applied to be equal to or greater than the required amount of oil. 8. The lubricating method according to 7. The lubrication method according to claim 8, wherein an amount of the rust preventive oil applied to the metal plate is 10 [mg / m ² ] or more and 150 [mg / m ² ] or less. 10. The lubrication method according to claim 6, wherein the rust preventive oil has a kinematic viscosity at 40 [° C.] of less than 15 [mm ² / s].

Images