KR101095485B1 - Process for manufacturing drawn can for aerosol and drawn can for aerosol - Google Patents

Abstract

The laminated steel sheet made of a raw material has a tensile strength (TS) of 800 MPa or less after processing in which the equivalent strain (εeｑ) becomes 1.6, and the sheet thickness (tb) at the cross section of the fracture portion after the tensile fracture and the thickness before the tensile fracture. (to) satisfies 0.25 ≦ tb / to. And in shaping | molding, it is work forming so that the following formula may be satisfied.

1.5≤h / (Rr), 2.8≤R / r ₁ , and 1.1≤r ₂ / r ₁

Where h is the height from the bottom of the can to the tip of the opening, r is the outer radius of the can body, R is the radius of the round blank before machining where the weight is equivalent to the final processed can, and r _{1 is the} opening. Outer radius of the tip, r ₂ : Outer radius of the bead

Aerosol, drawing steel sheet, laminate

Description

Manufacturing method of drawing processing can for aerosol and drawing processing can for aerosol {PROCESS FOR MANUFACTURING DRAWN CAN FOR AEROSOL AND DRAWN CAN FOR AEROSOL}

BACKGROUND OF THE INVENTION Field of the Invention The present invention relates to a method for producing a drawing process can for aerosol, which is used as a container such as various sprays, and a drawing process can for aerosol.

In the field of metal containers for aerosols, there are broadly divided welded cans and drawn cans. A welding can is a can bottom and a can lid (dome top) attached to a can body in which a rectangular flat plate is joined by welding in a cylindrical shape. When used for spraying purposes, a mounting cup with an injection valve is attached to the dome top.

The drawing process can is formed by the opening end side of the can body processed into a bottomed cylinder using a processing method such as impact processing, drawing redrawing processing, drawing redrawing processing, or ironing processing. The diameter is reduced to a diameter smaller than that of the mounting cup. Such a drawing processing can may be called a one-piece can and a mono block can.

In this way, the drawing can is a seamless can body, which is shaft-shaped in a smooth continuous shape from the can body toward the mounting cup, and the like.性) excellent. For this reason, drawing processing cans are widely used for applications in which the appearance of a package is important due to the nature of a product, for example, a fragrance, antiperspirants, hair tonics, and the like.

As a raw material used for these cans, it is common now that a steel plate is used for a welding can and aluminum is used for a drawing process can. As a reason why the steel plate was not used as a raw material of a drawing process can, the following points are divided roughly.

As a first reason, aluminum has no red rust like steel sheet. When the aerosol cans are placed in a humid environment, red rust may be generated when a steel sheet is used, and when a red rust is generated in one bay, the appearance of the aerosol can is remarkably damaged and the product value is deteriorated. .

As a second reason, since aluminum is softer than steel sheet, it is possible to form a bottomed cylindrical can body by using impact processing, drawing-redrawing processing, drawing-redrawing processing, ironing, or the like. It is relatively easy to shape the bead portion for reducing the opening end and further attaching the mounting cup to the opening end.

Here, the process of manufacturing the aerosol can which consists of a drawing process can as a raw material as a flat plate is shown in FIG. 1 and following.

1) a process of manufacturing a circular blank (blank) from a flat plate material,

2) a step of forming the can body by molding the circular blank into a bottomed cylindrical shape by a plurality of drawing operations (you may use ironing processing together);

3) a step of doming the can bottom of the can body into a shape that is convex toward the inner surface of the can,

4) a process of trimming the opening end side of the can body;

5) A step of shaft diameter processing (may be a plurality of processes) of the opening end side of the can body to a diameter less than the outside diameter of the can body,

6) A step of forming a bead portion by curl processing (may be a plurality of processes) at the tip of the opening end.

The aerosol cans are distributed in the market in a variety of sizes, and when the cans are obtained in accordance with the above-described various sizes by the above method, very high workability is required, and they are easily formed using steel sheets. It wasn't possible.

For this reason, aluminum is currently used in a drawing can for aerosols. However, since aluminum has low strength, it is necessary to thicken the plate thickness in an aerosol can with a high internal pressure. Therefore, in conjunction with the recent increase in the cost of aluminum-based metals, aerosol cans using aluminum have the disadvantage that the material cost is high. On the other hand, since steel sheet is high in strength and inexpensive, when it is used for an aerosol can, the thickness of a can body plate can be made thin while having sufficient can body strength, and there exists a possibility that a raw material cost can be reduced. In response to these phenomena, a technique for producing aerosol drawing cans using steel sheets has been desired.

As mentioned above, the first reason that steel sheet has not been used as a raw material for drawing cans is that corrosion resistance of steel sheet is inferior to aluminum. In this regard, Patent Literature 1 discloses a method of improving the corrosion resistance of the steel sheet itself as a technique for eliminating poor corrosion resistance. In patent document 1, the technique which makes steel plate itself stainless steel with high corrosion resistance is disclosed. However, since stainless steel is excellent in corrosion resistance but expensive, this method leads to an increase in can cost.

Patent Literature 2 discloses a technique of coating a steel plate surface with a metal having high corrosion resistance. That is, it is a technique which avoids the rust of the can bottom part of the aerosol can which was drawing ironing by using an aluminum coating steel plate. According to this method, there is a possibility that rust can be avoided in a can bottom having a low workability, but since the aluminum coating is damaged by the drawing ironing process, rust may be generated.

Patent Literature 3 discloses a technique related to an inner surface-painted metal container provided with a cured polyamide-imide coating film as a method of improving the corrosion resistance by coating a steel sheet surface with a paint film. Although this technique can use a steel plate as a raw material when used for an aerosol can, the embodiment regarding a steel plate only concerns a welding can, and there is no sufficient description about the corrosion resistance of a drawing can, and the effect is unclear. In the specification, although the technique may be applied to a molded can body or may be applied to a metal plate before molding, it may be processed later. In an embodiment, a can using aluminum having a coating film formed after forming the can body is described. The example which formed the coating film in the metal plate before shaping | molding, and processed it to the extent that it is made is not specifically shown. As a result of examination by the present inventors, when drawing and processing the steel plate coated with the thermosetting coating film, the coating film damaged, and sufficient corrosion resistance could not be obtained.

As a technique of reinforcing the fault of the said coating film, there exists a method of covering the steel plate surface with a film. Patent Literature 4 discloses a technique for obtaining an aerosol can with a drawing can using a steel sheet laminated with a biaxially stretched film of polyethylene terephthalate. According to this technique, since the can body after drawing processing is coat | covered with the laminated | multilayer film which is not damaged, it is excellent in corrosion resistance. However, in the can body obtained by this technique, corrosion resistance is maintained, as shown in the examples, the open end of the can body is not reduced in diameter, and the shaft diameter processing and curl processing necessary for obtaining an aerosol can from the flat plate material are performed. It does not exist, and the beauty of shape is lacking, and it does not replace a current aerosol can.

On the other hand, the second reason that steel sheet has not been used as a material for drawing cans is that the degree of processing must be very high in order to be applied to various sizes of aerosol cans on the market. It is in point.

Regarding the film laminated steel sheet to be applied to a thin-walled deep-drawn ironing can having a relatively high workability, Patent Documents 5 and 6 show that equivalent strain (εeｑ) is l. The technique which improves workability is disclosed by making the amount of tensile strength increase by the process into which it becomes more than a fixed. This technique assumes a low workability compared to the workability required in the above aerosol cans. Further, as a result of the inventors' review, when these steel sheets are applied to laminated steel sheets by drawing cans, problems arise in processing, and in particular, buckling when the open ends are compressed in the circumferential direction during shaft diameter machining. When this occurred, and when the bead portion by curl processing was formed, a phenomenon in which the open end of the can body was cracked by processing frequently occurred.

[Patent Document 1] Japanese Patent Publication No. 2003-500306

[Patent Document 2] Japanese Patent Laid-Open No. 63-168238

[Patent Document 3] Japanese Patent Application Laid-Open No. 9-39975

[Patent Document 4] Japanese Patent Application Laid-open No. Hei 1-228567

[Patent Document 5] Japanese Laid-Open Patent Publication No. 2002-317247

[Patent Document 6] Japanese Laid-Open Patent Publication No. 2002-317248

(Initiation of invention)

An object of this invention is to provide the manufacturing method of the aerosol drawing can which can be processed without buckling and a crack, and the aerosol drawing can which has sufficient can body strength and was excellent in corrosion resistance.

As a result of the investigation by the present inventors, it is not enough to simply use the laminated steel sheet for drawing processing of the prior art to manufacture the aerosol drawing processing can as a raw material, while using the laminated steel sheet excellent in corrosion resistance, It turned out that it is necessary to provide high workability to a laminated steel sheet.

This invention is made | formed based on the above recognition, The summary is as follows.

[1] A method for producing an aerosol drawing processing can made of a laminated steel sheet coated with an organic resin film and satisfying the following formula, wherein the laminated steel sheet has a significant strain (εeｑ) of 1.6 after processing. The tensile strength TS is 800 MPa or less, and the sheet thickness (tb) at the cross section of the fracture portion after tensile fracture and the sheet thickness (to) before the tensile fracture satisfy 0.25 ≦ tb / to. Method of manufacturing cans.

1.5≤h / (Rr), 2.8≤R / r ₁ , and 1.1≤r ₂ / r ₁

Where h is the height from the bottom of the can to the tip of the opening, r is the outer radius of the can body, R is the radius at the circular blank before machining that is equivalent to the final finished can. r ₁ : outer radius of the opening end, r ₂ : outer radius of the bead

[2] The laminate steel sheet according to the above [1], wherein the laminated steel sheet has a mass% of C: 0.0005 to 0.09%, Si: 0.1% or less, Mn: 1.0% or less, P: 0.02% or less, and S: 0.02% or less. , Al: 0.01 to 0.1%, N: 0.0060% or less, and the remainder is Fe and unavoidable impurities.

[3] The method for producing an aerosol drawing can according to [2], wherein the laminated steel sheet further contains B: 0.0001% to 0.003% by mass.

[4] The aerosol according to the above [2], wherein the laminated steel sheet further contains, by mass%, at least one of Ti: 0.001% to 0.05% and Nb: 0.001% to 0.05%. Method of manufacturing cans for drawing processing.

[5] The aerosol according to the above [3], wherein the laminated steel sheet further contains, by mass%, at least one of Ti: 0.001% to 0.05% and Nb: 0.001% to 0.05%. Method of manufacturing cans for drawing processing.

[6] In the above [1], the tensile strength (TS) after processing in which the equivalent strain (εeｑ) becomes 1.6 is 600 to 800 MPa, and the sheet thickness (tb) and the tensile fracture at the cross section of the fracture portion after the tensile fracture. The manufacturing method of the drawing process can for aerosols whose former plate | board thickness to satisfy 0.25 <= tb / to <0.40.

[7] An aerosol drawing processing can produced by the production method according to any one of [1] to [6].

In addition, in this specification, all% which shows the component of steel are mass%.

According to the present invention, by using a laminated steel sheet having specific properties and excellent corrosion resistance as a raw material, it is possible to manufacture aerosol drawing cans by avoiding buckling at the neck and cracks at the curl. As a result, it is possible to obtain a steel sheet as a raw material which is excellent in corrosion resistance and has a size and shape equivalent to those of conventional aerosol cans distributed in the market.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows the manufacturing process of the drawing process can for aerosol.

Fig. 2 is a diagram showing the relationship between can sizes of the present invention.

3 is a diagram showing the relationship between the can body size of the present invention.

4 is a diagram showing the relationship between the tensile strength TS and the ratio tb / to of the sheet thickness tb at the cross section of the fracture portion after the tensile fracture and the original sheet thickness to of the steel sheet.

Best Mode for Carrying Out the Invention [

Hereinafter, the present invention will be described in detail.

The aerosol can by the drawing process made into the object of this invention is process-molded by the process shown in FIG. 1 and the following.

(1) a step of producing a circular blank from a flat plate-shaped material,

(2) a step of forming a can body by shaping a circular blank into a bottomed cylindrical shape by a plurality of drawing processes (you may use ironing in combination),

(3) a process of processing a dome into a shape in which the can bottom of the can body is convex toward the inner surface of the can,

(4) process of trimming opening end side of can body,

(5) Process of shaft diameter processing (may be multiple times processing) to the opening end side of can body to diameter below the outer diameter of the can body,

(6) A step of forming a bead part by curl processing (may be a plurality of processes) at the tip of the opening end.

In the aerosol cans, various sizes are distributed in the market, and when the processing for obtaining the cans conforming to various sizes is performed by the above-described method, in the steps of (5) and (6) in FIG. 2, it is necessary to process the process drawing prescribed | regulated as follows using the size shown in FIG.

a) 1.5≤h / (R-r)

Here, h is the height from the bottom of the can to the tip of the opening, r is the outer radius of the can body, and R is the radius in the circular blank before processing, which is equivalent to the final processed can body. h / (R-r) is an index of the degree of processing concerning the deformation | transformation in the height direction of a can body.

b) 2.8≤R / r ₁

Here, r _1: the outer radius of the tip of the opening. r ₁ / R is an index of the degree of workability regarding the compressive deformation of the can body in the circumferential direction.

c) 1.1≤r ₂ / r ₁

Here, r ₂ is the outer radius of the bead portion. r <_2> / r <_1> is an index of the workability regarding expansion deformation at the time of curling an opening edge part.

In addition, the conditions of said processability are determined as follows.

First, the shape and size of the aerosol can to be produced are determined on the condition that it is equivalent to a commercial aerosol can. The shape and size of commercially available aerosol cans are described in various standards, for example, "Federation of European Aerosol Association Standard No.215, No.219, No.220". Accordingly, the size parameters r, h, and r ₁ in FIG. 2 can be determined. Next, the plate | board thickness of the laminated steel plate used for a can is determined from the point of intensity | strength, weight, and material cost required for a can. In addition, the machining process as shown in FIG. 1 is defined, and the plate | board thickness distribution in the step of (5) is determined. As a result, the weight of the final processed can is determined. Using this, the radius R in the circular blank before processing is calculated | required. Subsequently, the size parameter r ₂ of FIG. 3 can be determined by determining the shape of the bead portion. Furthermore, can be determined by the setting of the trim value at trimming at 4 in the radius (R ₀₎ of the circular blank is, in FIG. By performing these operations with respect to the shape and size of various commercially available aerosol cans, the conditions of the above processing degree are obtained. A), b) and c) are obtained in this manner.

Next, in this invention, the steel plate used as a raw material is demonstrated.

In order to manufacture aerosol drawing cans by avoiding buckling at the neck and cracks at the curl, which are conventional problems, the present inventors attach to a laminated steel sheet used as a raw material, and provide the laminated steel sheet with specific characteristics. I thought about solving the problem. First, a steel sheet having a chemical composition, a hot rolling condition, a cold rolling condition, an annealing condition, a temper-rolling condition, or the like is started to produce an aerosol can by drawing. The processing experiment was performed about the buckling at the time of shaft diameter processing which was a subject at the time, and the crack in the curl processing for forming the bead part. Processing conditions are the same as in the examples described later. By the sample, it was recognized that buckling occurs in the shaft diameter processing and cracks occurred in the curl processing. Therefore, although the properties of the material governing the shaft diameter workability were examined, the mechanical characteristic values obtained in the normal tensile test for evaluating the original plate before processing, that is, yield strength, yield point elongation, tensile strength, total In the elongation, uniform elongation, local elongation, or the Rankford value (r value), work hardening index (n value), hardness test, etc., the characteristics alone or in combination thereof may be used. No clear correlation could be found between buckling during shaft diameter processing and cracking in curl processing to form the bead portion.

As a reason for this, the workability evaluated in a normal tensile test is about 0.3-0.4 by a considerable deformation, but the aerosol can by drawing process requires high workability. Therefore, in the mechanical characteristic obtained by normal tension test etc., it is thought that the index which fully reflected the high workability at the time of carrying out shaft diameter processing and a curl processing cannot be obtained.

Therefore, the present inventors examine in detail the can body obtained by the actual processing experiment, and the factor which affects the buckling and the crack in the curl processing at the time of shaft diameter processing in the can body processed by high workability is examined. did.

First, as a result of trial calculations on the size and shape of various aerosol cans that are commercially available, the present invention has a working view of the opening end before the shaft diameter machining, i.e., in the step of FIG. In the equivalent strain (εeｑ), it was found to be about 1.6. Here, the equivalent strain εeｑ is a value obtained as follows from the plate thickness direction strain ε _t , the circumferential strain ε _θ , and the can height direction strain ε _φ of the side wall portion of the can body after processing. .

Buckling at the time of shaft diameter processing is a phenomenon in which the compressive stress in the circumferential direction acts when the opening end is reduced in diameter, and accordingly the opening end is buckled. It is thought that the occurrence of buckling in processing occurred because the open end was processed with a high workability, the material of the part became very hard by hardening by working, and workability was impaired. Therefore, in order to suppress generation | occurrence | production of this buckling, it is thought that it is necessary to appropriately define the material in an opening end part. And since the workability of an opening end part is about (epsilon) = 1.6 by considerable deformation, it is thought that the material of the part needs to be evaluated after providing this workability. Therefore, the relationship between the mechanical properties of the steel sheet and the buckling at the time of shaft diameter processing after the processing of the equivalent strain εe 변형 = 1.6 was investigated. As a result, it was found that buckling does not occur when the tensile strength TS after the processing at which the equivalent strain εeｑ = 1.6 is 800 MPa or less.

This is considered as follows. That is, it is hard to generate | occur | produce buckling in shaft diameter processing easily in the circumferential direction by compression deformation, Therefore, it is thought that generation | occurrence | production of buckling is suppressed in the intensity | strength of a critical value, here 800 MPa or less. In addition, as described herein, the tensile strength TS after performing a process such that the equivalent strain εeｑ = 1.6 is preferably low from the viewpoint of shaft diameter processing, but the lower the value, the lower the strength of the material constituting the can body. It leads to lowering, and further, intensity | strength as a can body becomes low. In order to ensure the strength required as a can body, it is preferable that the tensile strength TS after performing the process whose equivalent deformation | transformation (epsilon) e == 1.6 shall be 600 Mpa or more.

Although the processing method which gives the workability of equivalence distortion (epsilon) = 1.6 is best performed by actual drawing, it can be evaluated similarly even if it processes by other processing methods so that a deformation | transformation may become equivalent. The present inventors processed by rolling in addition to actual canning, but the considerable deformation | transformation at the time of a rolling process is carried out by substituting the circumferential deformation by plate width direction deformation with respect to the above-mentioned formula. The same can be obtained.

However, even if the shaft diameter processing could be performed by satisfying the above conditions, cracks sometimes occurred during the additional curl processing. In order to elucidate this phenomenon, the state of the opening end part at the time of curling was observed in detail. As a result, it was found that the curl crack occurs when the constriction of the tip of the open end that occurs with expansion in curl processing is large. In other words, it was recognized that this narrowed portion became the starting point of the crack and that the crack could be avoided by making it smaller. Moreover, it turned out that the precision of this narrow part can be summarized in relationship with the plate thickness in the cross section of the fracture | rupture part after the tensile fracture after processing in which the equivalent strain (εeｑ) becomes 1.6, and the original plate thickness of the steel plate before a tensile test. . Specifically, the constricted portion is formed under the condition that the sheet thickness (tb) at the cross section of the fracture portion after the tensile fracture after processing at which the equivalent strain (εeｑ) becomes 1.6 and the plate thickness (to) before the tensile fracture is 0.25≤tb / to It became small and it turned out that the generation of a curl crack can be avoided. tb / to is an index indicating a constriction along the break of the steel sheet. By setting this value to a value higher than or equal to a certain value, it is difficult for a partial constriction to occur due to the action of tension during curl processing. It leads to evasion. In other words, when the constricted portion occurs intensively in a specific portion in the curl portion, it is connected to creating a starting point of the curl crack. For this reason, it is conceivable that a material capable of distributing tension in the entire curled portion, without causing such a concave portion in a specific portion, is advantageous for cracking the curled portion. In addition, since it is preferable that a narrow part does not generate | occur | produce, it is preferable that tb / to is a value larger than 0.25, but the upper limit is 1 as evident from the definition.

The above examination result is shown in FIG. In Fig. 4, (circle) indicates that there is no problem in shaft diameter processing and curl processing,? Indicates that buckling occurs in shaft diameter processing, and? Indicates cracking in curl processing. From Fig. 4, the tensile strength TS after processing at which the equivalent strain (εe 1.6) becomes 1.6 is TS ≦ 800 MPa, the sheet thickness (tb) at the cross section of the fracture portion after the tensile fracture, and the sheet thickness (to) before the tensile fracture. By setting it as 0.25 <= tb / to, it turns out that a buckling does not generate | occur | produce at the time of shaft diameter processing and it does not generate a crack in curl processing. Therefore, in this invention, as a characteristic with a steel plate, the tensile strength TS after a process whose equivalence strain (epsilon) e becomes 1.6 is TS <= 800MPa, and the sheet thickness (tb) in the cross section of the fracture | rupture part after tensile fracture | rupture, The sheet thickness to before breaking is set to 0.25 ≦ tb / to.

Moreover, in the steel plate provided with the said characteristic, when the component was prescribed | regulated, when manufacturing the aerosol drawing process can, it discovered that the process problem was further reduced and advantageous. Hereinafter, a very suitable component range is described. In addition, all% is mass%.

C: 0.0005 to 0.09%

When C is less than 0.0005%, and when it is more than 0.09%, the probability that defects will be mixed in the steel sheet (scale mixing, inclusion mixing, etc.) increases, which may cause processing problems. When there is little C, it is thought that the decarburization process time of molten steel becomes long as a result, and the frequency of inclusions etc. increases in the meantime. On the other hand, when C is large, it is considered that a crack called apoptotic crack occurs when the molten steel solidifies. Therefore, the range of C is preferably 0.0005% or more and 0.09% or less.

Si: 0.1% or less

Si is an element that degrades the surface property of the steel sheet. If the content is high, Si is not preferable as a surface-treated steel sheet. In addition, Si is difficult to hot roll in order to harden the steel, and further harden the steel sheet as a final product. There is a case. From this viewpoint, Si is preferably 0.1% or less. Moreover, 0.050% or less is more preferable especially in the use with strict surface property requirements.

Mn: 1.0% or less

Mn is an element that hardens steel. When the content is large, the workability adversely affects the workability. In addition, Mn may be concentrated in the surface layer during annealing to deteriorate the surface properties. From this viewpoint, Mn is preferably 1.0% or less. In addition, when the content is less than 0.05%, even when the S content is reduced, it is difficult to avoid so-called hot shortness, and problems such as surface cracking occur, whereas when the content exceeds 0.6%, transformation point (transformation) (point) falls too much and it becomes difficult to obtain a preferable hot rolled sheet. Therefore, More preferably, they are 0.05% or more and 0.6% or less.

P: 0.02% or less

Although reduction of P content can aim at the improvement effect of corrosion resistance, since excessive reduction leads to increase of manufacturing cost, it is preferable to contain P in 0.02% or less from these balance. Moreover, when focusing on workability, it is more preferable to set it as 0.01% or less.

S: 0.05% or less

When S content increases, inclusions, such as MnS, increase, and local ductility is reduced and it causes a curl crack. Therefore, S content was limited to 0.05% or less. Moreover, in order to remarkably improve workability, it is preferable to set it as 0.010% or less.

Al: 0.01 to 0.1%,

When Al is less than 0.01%, and when it is more than 0.1%, the probability that defects will be mixed in the steel sheet (scale mixing, inclusion mixing, etc.) increases, which may cause processing problems. Al is added for the purpose of fixing and removing oxygen in molten steel as alumina, and alumina itself also floats and is absorbed by slag and removed from molten steel. However, when there is little Al, oxygen removal is not fully performed, and it can be considered that the oxide increases in steel, and this becomes an inclusion and the frequency of incorporation into a steel plate is low. On the other hand, when there is much Al, it can be considered that the produced alumina is not fully removed, and this itself becomes an inclusion. Therefore, the range of Al is preferably 0.01% or more and 0.1% or less.

N: 0.0060% or less,

When N is more than 0.0060%, the probability that defects will be mixed in the steel sheet (scale mixing, inclusion mixing, etc.) increases, which may cause processing problems. This is considered to be because when the N content is large, the hot ductility after the molten steel solidifies and the slag easily cracks. Therefore, the range of N is preferably 0.0060% or less.

Moreover, when containing the following elements further, when manufacturing the drawing process can used for an aerosol can, it discovered that a more advantageous situation is obtained.

B: 0.0001% to 0.003%

By containing B, the tendency for the occurrence frequency of the cracks in curl processing to fall at a high processing speed is recognized. The processing speed of the drawing can is usually expressed by the stroke speed of the press. Depending on the height of the can, it is usually a processing speed of several tens to hundreds of strokes per minute, on average about 100 strokes per minute. When it does not contain B, it is possible to process sufficiently stable operation | movement at an average speed | rate, and although it is possible to process even faster, it was recognized that the crack which arises in curl processing in some cases was recognized. On the other hand, when B is contained, cracks in the machining are less likely to occur even at a machining speed of 120 strokes or more per minute, thereby enabling stable operation. The reason for this is not clear, but it is thought that B is involved in segregation at the grain boundaries. This effect is not remarkable when the content is less than 0.0001%. On the other hand, the effect is saturated even if it is added 0.003% or more, and the addition of a large amount deteriorates the brittleness at the time of steel sheet manufacturing, and also the cost. Causes a rise. Therefore, the range of B is preferably 0.0001% or more and 0.003% or less.

At least one of Ti: 0.001% to 0.05% and Nb: 0.001% to 0.05%

By containing Ti and Nb, processing problems, such as drawing cracks, when processing a steel plate to a bottomed cylindrical can body are reduced. This is considered to be the result of the r value of a steel plate being improved by drawing of these elements, and drawing workability improved. In addition, although these elements are not essential, when these elements are contained, the tensile strength (TS) after the process to which the equivalent strain ((epsilon) (e)) necessary for the steel used for the manufacturing method of this invention turns into 1.6 will be TS <= 800MPa. It becomes easy to achieve. This is because by containing these elements, C in the steel is fixed as a carbide, and dissolved C decreases, so that the steel sheet is in a relatively soft state, and because it is originally soft, relatively low strength is obtained even after processing. I think. This effect is not remarkable when the content of Ti and Nb is less than 0.001% for both Ti and Nb. On the other hand, the effect is saturated even when 0.05% or more is added, leading to excessive increase in strength and increase in recrystallization temperature. In addition, a large amount of addition leads to an increase in cost. Therefore, the range of Ti and Nb is preferably 0.001% or more and 0.05% or less. Moreover, although these expresses the said effect at least 1 type, you may use 2 types.

In addition to the above, the following elements may be contained.

Ni: 0.5% or less, Cr: 0.5% or less, Cu: 0.5% or less

Ni, Cr, and Cu are all elements that lower the transformation point, and since the structure of the hot-rolled steel sheet is refined, excessively added causes difficulty in manufacturing in that it involves an increase in the load of cold rolling by hardening the hot-rolled sheet. In addition, the cost of steel may increase. Therefore, as for an upper limit, 0.5% is preferable in all.

In addition, remainder other than the above is Fe and an unavoidable impurity.

As mentioned above, in manufacturing the aerosol drawing process can of this invention, the laminated steel plate used as a raw material shall have the above-mentioned characteristic, Preferably it shall consist of the above-mentioned composition. In the present invention, these are the most important requirements. Thus, since the material itself has corrosion resistance and sufficient processability, it is possible to produce a drawing process can for aerosol even at a very high workability.

Specifically, in the present invention, the tensile strength (TS) after processing in which the equivalent strain (εeｑ) becomes 1.6 is TS ≦ 800 MPa, and the sheet thickness (tb) and tensile strength at the cross section of the fracture section after the tensile fracture. It is conditional that plate | board thickness to before break is 0.25 <= tb / to. As long as it has such a characteristic, you may use for the original board of the laminated steel plate used for this invention. However, the point which contains said component is a process advantage is as having mentioned above.

Although it does not specifically limit as a manufacturing method of the steel plate provided with these characteristics, A typical thing is described below.

As an example of the component of steel, it is as showing below.

In mass%, C: 0.0005% to 0.09%, Al: 0.01 to 0.1%, N: 0.0060% or less, or further Ti: 0.001% to 0.05%, Nb: 0.001% to 0.05% Or more, or further, B: 0.0001% to 0.003%, in addition, Si: 0.1% or less, Mn: 1.0% or less, S: 0.02% or less, P: 0.02% or less, Ni: 0.5% or less, You may contain Cr: 0.5% or less and Cu: 0.5% or less. The steel containing the said component is made into slab by the continuous casting method after a solvent. After cooling, the slab is heated to 1100 ° C. to 1300 ° C., and then hot rolled at a finishing temperature equal to or higher than the Ar 3 transformation point, and wound at a winding temperature of 540 ° C. to 720 ° C. Subsequently, after cooling, this hot rolling coil is pickled and rolled at a rolling rate of 80% to 94%. At this time, in order to suppress the generation of the edges at the time of drawing processing, it is preferable that rolling ratio is 85%-92%. Subsequently, the cold rolled coil is degreased to remove the lubricant used in cold rolling, and then annealed by a box annealing method or a continuous annealing method. It is preferable to perform the annealing method by the continuous annealing method which is excellent by productivity and the uniformity of material. In the continuous annealing method, the steel sheet is heated above the recrystallization temperature, then cracked to complete recrystallization, and then cooled. In cooling, it is preferable to cool to about 400 degreeC at the cooling rate of about 20 degree-C / s or more from a crack temperature, and to perform the overaging process which correct | amends for a fixed time at this temperature.

Although it does not specifically limit as a film which comprises the film laminated steel plate used by this invention, The following are preferable from the objective which removes the possibility of the film damage at the time of processing to the maximum.

Obtained by the polycondensation of a dicarboxylic acid component and a diol component, the dicarboxylic acid component consists of terephthalic acid or terephthalic acid and isophthalic acid, the diol component consists of ethylene glycol and / or butylene glycol, and ethylene terephthalate or The repeating unit which consists of butylene terephthalate is any resin chosen from following (1)-(5) which is 84% or more by mol% ratio.

(1) polyethylene terephthalate-polyethylene isophthalate copolymer

(2) polyethylene terephthalate

(3) Polybutylene Terephthalate-Polyethylene Terephthalate Copolymer

(4) polyethylene terephthalate-polyethylene isophthalate-polybutylene terephthalate copolymer

(5) polybutylene terephthalate

In addition, the laminate resin layer is a resin containing at least an outermost layer as a main component of thermoplastic polyester whose main phase is a resin based on the above-mentioned resins (1) to (5). It is preferable that an auxiliary phase consists of mixed resin which consists of a polyolefin. Here, it is preferable that the said polyolefin consists of 1 or more types of polyethylene, a polypropylene, and an ionomer. Moreover, since the surface orientation coefficient of the surface resin layer of a laminated resin layer is 0.04 or less, the possibility of film damage reduces.

In addition, the laminated steel sheet used by this invention makes a steel plate a board | substrate. It is preferable to use the surface-treated steel plate which gave the surface the various surface treatment for the steel plate. In particular, a surface-treated steel sheet (so-called TFS) in which a lower layer is formed of a two-layer coating made of metal chromium and an upper layer of chromium hydroxide is optimal. Although it does not specifically limit about the adhesion amount of TFS metal chromium layer and a chromium hydroxide layer, It is preferable to set it as the range of 70-200 mg / m <2> and chromium hydroxide layer in the range of 70-30 mg / cm <2> in both Cr conversion. .

Next, the manufacturing method of the aerosol drawing process can of this invention is demonstrated.

The aerosol drawing processing can of this invention is equipped with the above-mentioned characteristic, is made into the laminated steel sheet which coat | covered the organic resin film, and is shape | molded so that the following formula may be satisfied. The detail of each process is as follows.

1.5≤h / (Rr), 2.8≤R / r ₁ , and 1.1≤r ₂ / r ₁

Where h is the height from the bottom of the can to the tip of the opening, r is the outer radius of the can body, R is the radius in the round blank before processing, where the weight is equivalent to the final processed can, and r ₁ is the outer radius of the opening tip. , R ₁ : radius of circular blank position before drawing processing corresponding to the opening end, r ₂ : outer radius of the bead

Process of manufacturing circular blanks from flat plate material

In creating a circular blank, a method using a circular cutter and a die is preferable. Moreover, a circular blank can also be created simultaneously with the 1st process of several times of drawing processing performed after producing a circular blank. In addition, although noncircular blanks slightly different from perfect circles may be used in order to suppress the occurrence of corners in the drawing process, the present invention employs this method without any problem. The outer circumferential shape may not necessarily be a circle.

A step of forming the can body by molding the circular blank into a bottomed cylindrical shape by a plurality of drawing processes

In order to shape a laminated steel sheet into the bottomed cylinder which comprises the can body of a drawing process can, the method of obtaining a predetermined height by performing several times of drawing processing to a circular blank is used. The number of drawing times and the drawing rate in a plurality of drawing processes can be appropriately selected. In order to simplify the molding process, it is preferable to perform a small number of drawings, but on the other hand, a low drawing rate, that is, strict processing is required. In order to simplify molding, a drawing frequency of 10 or less times is preferable. The drawing rate is preferably 0.4 or more when the first drawing is performed from the circular blank, and 0.5 or more in the subsequent drawing (redrawing) process.

In addition, in drawing processing in this invention, although drawing based on multiple times of drawing processing, the method of performing drawing-ironing process which added the ironing process is also employable. Further, in a plurality of drawing operations, a thinning drawing for reducing the plate thickness by using bending and spreading deformation at the drawing die shoulder in a state where a rear tension is applied by a blank holder pressure. Processing and thinning drawing-ironing process which use ironing together can also be employ | adopted.

Lubrication conditions are affected by the drawing process. Laminated steel sheet has the function of enhancing the lubricity itself because the coated film is flexible and the surface is smooth, and there is no need to use a lubricant in drawing processing, but in the case of lowering the drawing rate, the lubricant Preference is given to using. The kind of lubricant can be suitably selected as long as the said objective is achieved.

In connection with the drawing process, the plate thickness of the side wall portion of the can body changes with respect to the original sheet thickness. When the sheet thickness change is expressed using the average plate thickness change (t / t ₀ ) using the average plate thickness (t) and the original plate thickness (t ₀ ) over the entire can height, t / t in the drawing-redrawing process _There exists a tendency to become ₀ > 1, and it becomes t / t ₀ <1 in drawing-ironing processing, thinning drawing processing, thinning drawing-ironing process, etc. In consideration of the damage of the laminated steel sheet accompanying the processing, it is preferable that the average plate thickness change rate is in the range of 0.5 <t / t ₀ <1.5.

Cans cans Bottom  Cans Inward  Process of dome processing into convex shape

Aerosol cans for the purpose of the present invention require a pressure resistance of at least 15 kgf / cm 2 to fill the propellant. Therefore, it is necessary to pay special attention to can bottom part about the pressure rise inside a can. The pressure inside the can body of the bottomed cylinder exerts a stress in the direction in which the can body is extended in the circumferential direction with respect to the can body side wall. However, the can body member is sufficiently hardened by drawing processing and does not deform by the action by internal pressure. However, since the internal pressure acts in the state in which the outer edge part is restrained by the can body, the can bottom part deforms toward the outer side of the can when the internal pressure is high. Therefore, the bottom of the can needs to consider the influence of internal pressure. In order to suppress deformation of the bottom of the can due to internal pressure, a method of increasing the plate thickness of the can bottom and increasing the strength of the member is effective, and it is suitable to make the shape into a dome shape of the shape which is convex toward the inside of the can. As the method of dome processing, the method of pressing the bottom of a can with a metal mold | die which has an external shape of a dome shape is suitable.

Can torso Opening end side  Trimming process

It does not specifically limit as a method of trim processing. For example, a press method for trimming by an outer blade having a circular hole and a cylindrical inner blade, a pinch method, or a solid cylindrical inner blade that rotates with each other. (Insertion into a can body), a spin method of trimming by a sharp outer disk-shaped edge, and the like.

Can torso Opening end side  Can torso Outer diameter  Process of shaft diameter processing with the following diameter

In an aerosol can, it is necessary to reduce the opening end to the diameter of the cylinder or less in order to attach the mounting cup to the opening of the can body. As a method of shaft diameter processing, methods, such as the die neck method which presses an opening end part to an inner taper-shaped die, and performs a shaft diameter, the spin neck method which pushes a rotary tool to a can body opening end part radially inward in a can body, and perform a shaft diameter, etc. Can be adopted. From the viewpoint of excluding the damage of the film as much as possible, the die neck method is suitable. In the die neck method, it is preferable to process between dividing the radius r of the can body from the radius r ₁ after the final shaft diameter into a plurality of steps. At this time, when the degree of workability per once increases the risk of wrinkles occurring in the shaft diameter machining, the shaft diameter ratio (radius after the shaft diameter / radius before the shaft diameter machining) is preferably set to 0.7 or more. Laminated steel sheet has the function of improving the lubricity itself because the coated film is flexible and the surface is smooth, and there is no need to use lubricant especially for shaft diameter processing, but it is possible to minimize the damage of the film by sliding with the tool. It is preferable to use a lubricating agent from a viewpoint which excludes. The kind of lubricant can be suitably selected as long as the said objective is achieved.

Opening At the tip  By curl processing Bead part  Forming process

In an aerosol can, a bead portion, which is a structure for attaching a mounting cup to an opening end, is formed in order to attach a mounting cup (having an injection valve for ejecting a proper amount of contents) to the opening end. The bead portion is processed by curl molding. The method of curl processing presses a can body opening end part by the die curl system which presses a can body opening end part to the curl die which has an arc shaped curved part at the base part of a cylindrical insert, or a roll which has an arc shape curved part. Spinning method etc. can be employ | adopted.

Heat treatment

In the present invention, it is effective to perform heat treatment in the middle of a series of processing steps. By damaging the stress accompanying the deformation | transformation applied to the film of the laminated steel plate in a process by heat processing, the film damage in subsequent process is reduced. As conditions for heat processing, it is suitable that it is heat processing more than the glass transition point of a film and melting | fusing point of a film +30 degrees C or less. Moreover, it is preferable to quench to the temperature which is less than the glass transition point of a film within 30 second immediately after heat processing.

Example  One

Hereinafter, an Example is described.

The drawing process can was manufactured by the processing process shown below.

Process of manufacturing circular blanks from flat plate material

The steel which consists of a component shown in Table 1 was manufactured according to the manufacturing conditions shown in Table 2, and the steel plate of plate thickness 0.21mm was obtained. Subsequently, the laminated steel sheet which laminated | stacked the micro polyethylene terephthalate film which is 25 micrometers in thickness by the heat-sealing method on both surfaces of TFS which makes this obtained steel plate a raw material, and produced the circular blank using this laminated steel sheet as a raw material. The blank diameter was 86 mm.

The process of shaping a can body by shape | molding a circular blank in bottom shape cylindrical shape by several drawing processes.

Drawing process was performed 5 times about the circular blank obtained by the above, and the drawing can was shape | molded.

Each drawing rate is shown in Table 3. In the fifth drawing step, ironing was used in combination with a plate thickness reduction rate of 20% (ratio of average plate thickness reduction in the can height direction of the can body after drawing to the thickness of the steel plate original without the film). .

Cans cans Bottom  Cans On the inside  Process of dome processing into convex shape

A hemispherical protruding process having a depth of 6 mm was performed at the bottom of the can.

Can torso Opening end side  Trimming process

The processing of the trim was performed by trimming the upper end of the can by about 2 mm using a method of trimming by a press method using an outer blade having a circular hole and a cylindrical inner blade.

Can torso Opening end side  Can torso Outer diameter  In diameter less than 縮 徑 Processing

In the die neck method which presses the inner tapered die on the upper end of the can body, and performs the shaft diameter, the shaft diameter processing of 8 stages is performed at the shaft diameter ratio shown in Table 4 about the process from the diameter of the can body to the final diameter. Done. Therefore, h / (Rr) = 1.9 , R / r 1 = 3.8 to obtain a drawing of the can.

Opening At the tip  By curl processing Bead part  Forming process

Shaft diameter and touched the inner surface to the opening end upper portion after forming by pressing of arc-shaped die using the die-curling method which performs local processing was carried out at a local processing that is r ₂ / r ₁ = 1.3 to the expansion rate of the dimensions shown in FIG.

In addition, in this invention, although it does not have a direct relationship with a process problem, in the sense of avoiding film damage of a laminated steel plate, between the process of dome processing and the process of trimming a can bottom part in the shape which becomes convex toward a can inner surface side. In the can body, heating was performed for 5 minutes using the hot air heating furnace which set the temperature in a furnace at 220 degreeC, and the heat processing which put in a water tank of room temperature immediately after this and performed cooling was performed.

In addition, a series of drawing processing, dome processing, trimming, shaft diameter processing, and curl processing were performed on the conditions that the stroke speed of a press is 80-160 strokes per minute.

The following test was done about the drawing process can obtained by the above, and performance was evaluated.

The tensile strength( TS ) And tb Of to

Rolling was performed on the test material (the above-described laminated steel sheet used as a material) to give a workability of equivalent strain εeｑ = 1.6. After this was processed into JIS 13B test piece, the tensile test which made rolling direction into the tension direction was done, and tensile strength (TS) was measured. Here, the tensile velocity was 10 mm / min. In addition, since the test material is a laminated steel sheet, although the laminated film is coat | covered on the steel plate surface, when carrying out a tension test, the film was removed beforehand. In addition, after the tensile test, the plate thickness (to) before the tensile test (before the tensile fracture) and the plate thickness (tb) at the cross section of the fracture portion after the tensile fracture were measured to calculate tb / to.

Shaft Diameter Machinability

When the shaft diameter processing was performed, the thing that the occurrence frequency of buckling was 100 ppm or less and ○ and the thing exceeding 100 ppm was made into x regardless of the number of times of shaft diameter processing.

Curl processability

At the time of curl processing, the thing where the occurrence frequency of a crack was 100 ppm or less was made into (circle) and the thing exceeding 100 ppm as x. In addition, since curling is performed after said shaft diameter processing, evaluation was not performed when shaft diameter processing was rejected. In addition, since the inferior shaft workability and curl workability did not hold | maintain as a product in operation, the following evaluation was not performed.

Machining defect

The finished drawing can was examined for processing defects which are thought to be due to the steel sheet, such as pinholes in the sidewall portions and flaw-shaped defects along the rolling direction of the steel sheet. The occurrence of such a defect is very rare and the frequency of occurrence is 50 ppm or less. (Circle) and thing less than 10 ppm were made into what the process defect generate | occur | produced in the generation frequency of 10-50 ppm in continuous processing.

High Speed Machinability

The processing speed of the drawing can is usually expressed by the stroke speed of the press. Stroke speed: It was set as ○ that the frequency of occurrence of cracks in curling at a machining speed of 80 to 120 strokes per minute was 50 ppm or less, which is not a problem in normal operation. Moreover, stroke speed: It was set as (circle) that the occurrence frequency of a crack was 50 ppm or less in curling at the machining speed of 120 strokes or more per minute.

Drawing processability

In the continuous drawing processing, cracks may occur in the drawing processing in some cases even without inclusions in steel sheets or the like. Most of this occurred near the bottom of the can body. Problems in such a process are very rare, and it can be avoided by appropriately setting the blank holder force, the lubrication conditions, etc. in the drawing process, and it is set that ○ can be processed continuously at an occurrence frequency of 50 ppm or less by such an operation. In addition, it was set as (circle) that the frequency of occurrence is 10 ppm or less.

Table 5 shows the results obtained by the above.

From Table 5, the examples of the present invention in which TS and tb / to are within the scope of the present invention also show good performance. Incidentally, the fact that C, Al and N are within the scope of the present invention has a lower frequency of occurrence of processing defects. In addition, containing B is excellent in high speed workability, and containing Ti and Nb is excellent in drawing workability.

Inventive Examples r, s, t, and u have no particular problem in performance, but since some of the components deviate from a very suitable range, pinholes are generated on the sidewalls of the drawing can as compared with the present invention in a range where the components are very suitable. Some processing defects, such as, were generated. However, the occurrence frequency is 50 ppm or less, and there is no problem even in continuous processing. On the other hand, in Comparative Examples c, d, and k, TS is high outside the scope of the present invention, and shaft diameter workability is inferior. In Comparative Examples f and h, tb / to is small outside the scope of the present invention, and curl processing properties are inferior.

The present invention is most suitable as a drawing processing can for aerosols. In addition to aerosol cans, it is also suitably used for applications requiring can body strength, corrosion resistance, appearance, and the like at a high degree of processing as contemplated in the present invention, and application to general two-piece cans is also possible.

Claims (7)

As a manufacturing method of the drawing processing can for aerosol which uses the laminated steel plate which coated the organic resin film as a raw material, and satisfy | fills the following formula, The laminated steel sheet has a tensile strength (TS) after processing in which an equivalent strain (εe strain) of 1.6 is 800 MPa or less, and the sheet thickness (tb) at the cross section of the fracture portion after the tensile fracture and the plate before the tensile fracture. A method for producing an aerosol drawing processing can, characterized in that the thickness (to) satisfies 0.25 ≦ tb / to. 1.5≤h / (Rr), 2.8≤R / r ₁ , and 1.1≤r ₂ / r ₁ Where h is the height from the bottom of the can to the tip of the opening, r is the outer radius of the can body, R is the radius at the circular blank before machining that is equivalent to the final finished can. r ₁ : outer radius of the opening end, r ₂ : Outside radius of the bead part The method of claim 1, The laminated steel sheet is, in mass%, C: 0.0005 to 0.09%, Si: 0.1% or less, Mn: 1.0% or less, P: 0.02% or less, S: 0.02% or less, Al: 0.01 to 0.1%, N: It contains 0.0060% or less, and remainder is Fe and an unavoidable impurity, The manufacturing method of the aerosol drawing process can. 3. The method of claim 2, The said laminated steel sheet further contains B: 0.0001%-0.003% by mass%, The manufacturing method of the aerosol drawing processing can characterized by the above-mentioned. 3. The method of claim 2, The laminated steel sheet further contains, in mass%, at least one of Ti: 0.001% to 0.05% and Nb: 0.001% to 0.05%. The method of claim 3, The laminated steel sheet further contains, in mass%, at least one of Ti: 0.001% to 0.05% and Nb: 0.001% to 0.05%. The method of claim 1, Tensile strength (TS) after the process in which the equivalent strain (εe 1.6) becomes 1.6 is 600-800 MPa, and the plate thickness (tb) at the cross section of the fracture portion after the tensile fracture and the plate thickness (to) before the tensile fracture is 0.25 ≦ tb The manufacturing method of the drawing process can for aerosol which satisfy | fills /to<=0.40. The drawing processing can for aerosol manufactured by the manufacturing method in any one of Claims 1-6.

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