JP3504546B2 - Apparatus and method for pressing welded portion of drum and drum manufacturing apparatus - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drum can welding portion pressing device for pressing a welding portion extending in an axial direction of an iron drum can having a capacity of, for example, 200 liters or 55 gallons. The present invention relates to a drum can welding part pressing method executed by the drum can welding part pressing device, and a drum can manufacturing device equipped with the drum can welding part pressing device.

[0002]

2. Description of the Related Art The body portion of an iron drum having a capacity of 200 liters or 55 gallons is formed by rolling a thin steel sheet into a cylindrical shape, and the both end portions along the axial direction of the cylindrical thin steel sheet are It is formed by welding. The body portion is subjected to flange processing, so-called flanging, on both ends thereof,
In addition, after the reinforcing ring is formed over the entire circumference of the body, oil and dirt adhering to the surface are removed. After the cleaning, the ground plate and, if necessary, the top plate are attached to both ends of the body by winding and the like, and the drum can is manufactured.

Since the weld portion along the axial direction in the body portion has oxide scale, the adhesion of the coating film in the weld portion during coating of the body portion is deteriorated,
Further, since the steel plates are superposed on each other at the welded portion, a step is generated, and the winding tightening at the time of attaching the base plate or the top plate may be incomplete. Therefore, in order to solve such a problem, there is a weld portion shaping device disclosed in, for example, Japanese Patent No. 2583840 and shown in FIG. 16, in which the weld portion is crushed by a roller. The welding part shaping device is roughly classified into a base 3 having a support die 2.
And the pressurizing device 4, and operates as follows. That is, the pressure roller 13 and the pressure cylinder 11 for pressing the welded portion 1A against the cylinder 1 placed on the support die 2 by bringing the welded portion 1A of the cylinder 1 into contact with the support die 2. The slider 8 provided at one end is connected to the cylindrical body 1 from the pressing device 4.
Insert inside. Then, the pressure cylinder 11 is operated to press the welding portion 1A from the inner surface side of the cylindrical body 1 to the supporting die 2 side by the pressure roller 13, while moving the slider 8 along the welding portion 1A, 1A is flattened and the oxide scale is removed.

[0004]

However, in the above welding portion shaping device, since the pressure roller 13 is inserted into the cylindrical body 1, the slider 8 is inevitably long, and thus such a long length is required. The mechanism for holding and moving the large slider 8 also becomes large. Furthermore, since pressure is applied by the pressure roller 13 provided at one end portion of the long slider 8 located on the opposite side of the support side, it is difficult to obtain sufficient pressure by the pressure roller 13. Further, it is difficult to obtain the rigidity of the slider 8.

Further, as shown in the figure, the cylindrical body 1 remains mounted on the support die 2 and is not supported. On the other hand, the support die 2 has a concave curved surface whose upper surface extends along the surface of the cylindrical body 1, but has a radius of curvature of the cylindrical body 1.
It is set slightly larger than the radius of. Therefore,
During the pressing operation by the pressure roller 13, the cylindrical body 1
It can roll in the circumferential direction on the support die 2 and lacks stability. Therefore, along the welded portion 1A, the welded portion 1
It is also conceivable that the pressure roller 13 cannot move accurately on A. On the other hand, if the cylindrical body 1 is supported, in the structure shown in the figure, a method of sandwiching the cylindrical body 1 from both ends of the cylindrical body 1 in the axial direction of the cylindrical body 1 is conceivable. The holding method may cause deformation of the cylindrical body 1. Therefore, even if the structure for supporting the cylindrical body 1 is adopted, sufficient support cannot be achieved, and the welded portion 1 is still not supported.
It is also conceivable that the pressure roller 13 cannot move accurately on A. Further, according to the above patent publication, only one welding part shaping device is installed, and there is no disclosure about backup in the event of a failure. Further, even in the normal operation, it takes a long time to process one cylindrical body 1 with one welding part shaping device, which causes a problem in actual operation.

In the manufacture of a steel drum using the weld shaping device disclosed in the above patent publication, the cylindrical body 1 is used.
By performing cold crushing on the welded portion 1A with the pressure roller 13, bulging portions are formed at both ends of the cylindrical body 1. After performing the cold crushing operation, the step of cutting the bulging portion is performed. . Thus, in the weld shaping device, the overhanging portion is cut after the cold crushing operation,
There is also a problem in that the order of steps is fixed, and the degree of freedom in machine layout in the manufacturing line is low.

Further, since the above-mentioned patent publication describes that the cold crushing causes the overhanging portions to be formed at both ends of the cylindrical body 1, the pressure roller 13 can be used as the cylindrical body 1. It is considered that rolling travel is performed on the welded portion 1A over the entire length of. That is, the pressure roller 13 bites into one end of the cylindrical body 1 in a pressurized state, runs on the welded portion 1A, and comes out from the other end of the cylindrical body 1. In such a situation, generally, the one end portion and the other end portion in the axial direction of the can body have a smaller binding force of the material around the rolling point by the pressure roller than the central portion of the can body. Deformation becomes large. Therefore, as shown in FIGS. 17 and 18, regardless of the plate thickness of the can body, the plate thickness of the can is reduced or unsteady deformation occurs from the end of the can to the inside of the can by about several tens of mm. Therefore, the mechanical properties of the can material at both ends of the can deteriorate. Further, in the manufacture of drums, the can end is subjected to the above-mentioned flanging, winding, and the like in order to attach the base plate and the top plate, but due to the deterioration of the mechanical properties, the can end is not Damage such as cracks easily occurs. It should be noted that FIG. 17 is a view when the pressure roller is engaged with one end portion of the can body, and FIG. 18 is a view when the pressure roller is pulled out from the other end portion of the can body. Further, the solid line shown in FIGS. 17 and 18 shows the case where the plate thickness is 1.6 mm, the fine dotted line shows the case of 1.2 mm, and the rough dotted line shows the case of 1 mm.

The present invention has been made to solve the above problems, and it is possible to accurately press the welded portion of the body portion of the drum can, and the welded portion has a uniform shape over its entire length. (EN) Provided are a drum can welding portion pressing device which can have mechanical properties, a drum can welding portion pressing method executed by the drum can welding portion pressing device, and a drum can manufacturing device including the drum can welding portion pressing device. With the goal.

[0009]

In order to achieve the above object, the present invention is configured as follows. A drum can welding portion pressing device according to a first aspect of the present invention is a base plate, which is manufactured by welding both side ends of the steel plate extending in the axial direction of the cylindrical body formed by bending the steel plate to each other. A drum can welding portion pressing device for crushing the welding portions at the both end portions with respect to the drum can body portion before mounting the top plate,
A support body inserted inside the drum can body portion, extending over the entire length of the welded portion along the axial direction and on the inner peripheral surface of the drum can body portion in the circumferential direction of the drum can body portion. A pressure receiving portion that extends along and covers at least the welded portion and is in contact with the welded portion during the crushing operation of the welded portion, and is located on both sides of the pressure receiving portion in the circumferential direction. The support having a displacement prevention portion for preventing the displacement of the drum can body portion during a crushing operation, and the support body is arranged to face the support body so as to sandwich the welded portion outside the drum can body portion, A pressing movement device that moves along the axial direction while pressing the welding portion against the support during the crushing operation of the welding portion to crush the welding portion and flatten it. It is characterized in.

Further, the pressing moving device may be configured to perform the crushing operation with respect to a central portion in the axial direction of the welded portion along the axial direction.

In the drum can manufacturing apparatus according to the second aspect of the present invention, a transport device for sequentially transporting a plurality of drum can body portions in the transport direction along the transport path is sandwiched between the transport device. The two drum can welding portion pressing devices according to any one of claims 1 to 3, which are respectively disposed on both sides, and the drum can body that has been conveyed by the conveying device to the drum can welding portion pressing device. At the same time as mounting the part to one of the drum can welding portion pressing devices, the transfer device that separates the drum can body portion that has completed the flattening of the welding portion from the other drum can welding portion pressing device and returns to the transport path, It is characterized by having.

In the drum can manufacturing apparatus of the second aspect, the drum can welding portion pressing device performs a crushing operation on a central portion in the axial direction of the welding portion along the axial direction of the drum can body portion. It can also be configured to.

Further, in the drum can manufacturing apparatus of the second aspect, the drum can body, which is disposed on the pre-process side or the post-process side of the drum can welding portion pressing device, excluding the central portion of the welding portion in the axial direction. It is configured to further include an end portion pressing device that clamps and presses both end portions of the weld portion located at both end portions in the axial direction of the portion along the thickness direction of the weld portion to perform the crushing operation of the both end portions. You can also do it.

In the drum can welding portion pressing method according to the third aspect of the present invention, both side ends of the steel plate extending in the axial direction of the cylindrical body formed by bending the steel plate are welded to each other. A drum can welding part pressing method for crushing the welded parts at the both end portions with respect to the drum can body part before the installation of the main plate and the top plate, which is the center of the weld part in the axial direction of the drum can body part. For the part, the roll is moved and crushed along the axial direction, and both end portions of the welded portion located at both axial end portions of the drum can body portion excluding the central portion are arranged along the thickness direction of the welded portion. The above-mentioned both ends are clamped and pressed to perform a crushing operation.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION A drum can welding portion pressing device, a drum can welding portion pressing method executed by the drum can welding portion pressing device, and a drum can equipped with the drum can welding portion pressing device according to an embodiment of the present invention. About manufacturing equipment,
A description will be given below with reference to the drawings. In each figure, the same components are designated by the same reference numerals. In the present embodiment, a drum having a capacity of 200 liters is taken as an example. However, the drum can welding portion pressing device and the drum can manufacturing device of the present embodiment can process the drum can body portion with the above-mentioned 200.
It is not limited to liter drums. That is,
The drum can welding portion pressing device of the present embodiment, the drum can welding portion pressing method, and the drum can manufacturing device have a welding portion along the axial direction of the body portion formed by rolling the steel plate,
Further, it can be applied to a body portion that requires flattening of the welded portion.

For example, as shown in FIG. 5, the drum can manufacturing apparatus 101 according to the present embodiment has a conveying device 110.
, Drum can welding portion pressing device 120, and transfer device 130
Although not shown in FIG. 5, the drum can manufacturing apparatus 101 includes an apparatus for manufacturing a cylindrical body by rolling a steel plate, and the above-described apparatus extending in the axial direction of the manufactured cylindrical body. Welded both ends of the steel sheet and welded part 2 as shown in FIG.
An apparatus for producing the drum can body portion 200 having 01 is installed on the front process side of the drum can weld portion pressing device 120, and on the rear process side of the drum can weld portion pressing device 120 along the axial direction of the drum can body portion 200. A device for forging a level difference at both ends of the welded portion 201, flattening the flattened portion, and then cutting the overhanging portions produced at the both ends by welding and forging.
An example of a mash cutter device that functions as an end pressing device, a device that performs flange processing on both ends of the drum can body portion 200, a device that forms a ring for reinforcement over the entire circumference of the body, and is attached to the surface. A cleaning device for removing oil, dirt, etc. is installed, and a device for attaching a base plate by winding or the like to the both ends of the drum can body portion 200 and, if necessary, a top plate is installed.

Incidentally, as shown in FIG. 12, the mash cutter device 301 is provided on the rear process side of the drum can welding portion pressing device 120 as described above in this embodiment.
It can also be provided on the pre-process side of the drum can welding portion pressing device 120. Further, reference numeral 351 corresponds to an apparatus for manufacturing the drum can body portion 200 described above. The mash cutter device 301 is a known device having a structure disclosed in, for example, Japanese Patent Laid-Open No. 7-16680, and as shown in FIGS. 13 and 14, a press device 302 and a cutting device 3 are provided.
And 03. As shown in FIGS. 12 and 13, the drum can body portion 200 having the welded portion 201 has
Since it is transported along the transport direction 111 along the line 13, the pressing device 302 and the cutting device 303 are arranged one by one in a set corresponding to both axial end portions of the drum can body portion 200. Each set of pressing device 302 and cutting device 30
Each of 3 is movable in the axial direction of the drum body portion 200.

The pressing device 302 includes a lower die 3021 that is moved up and down by a hydraulic cylinder, and an upper die 3022 that is fixed so as to face the lower die 3021. Lower mold 3021
The drum can body portion 200 is disposed so as to be sandwiched between the upper die 3022 and the upper die 3022. Therefore, the upper surface of the lower mold 3021 and the lower surface of the upper mold 3022 form a cylindrical surface having the same shape as the cylindrical shape of the drum can body portion 200. or,
Lower mold 302 along the axial direction of the drum body 200
1 has a length of about 35 mm and a width of about 55 mm.
The press device 302 configured as described above is used in the lower mold 30.
21 is moved to the upper mold 3022 side, and both end portions of the welded portion 201 located at both end portions in the axial direction of the drum can body portion are sandwiched and pressed along the thickness direction of the welded portion 201 to press the both end portions. Forging and flattening, that is, crushing, are performed.

The cutting device 303 includes a blade 3031 that moves up and down with a hydraulic cylinder, the blade 3031 that raises and lowers the overhanging portions formed at the both ends by the welding and the forging, and the lower die 3021.
The disconnection operation is performed by and.

In the present embodiment, the transfer device 110 is
The drum can body portions 200-1, 200-2, 200-3, ... Mounted on the transport conveyor 112 are conveyed one by one, for example, one pitch so as to be continuously carried into the drum can welding portion pressing device 120. The drum can body part 2
This is a device for sequentially transporting 00 in the transport direction 111 indicated by the arrow. Therefore, the drum can welding portion pressing device 120 described above is provided along the transportation path 113 along which the transportation conveyor 112 extends.
Further, the mash cutter device 301, the flange processing device, the ring forming device, and the like are installed.

The detailed structure of the drum can welding portion pressing device 120 will be described below. In the present embodiment, the drum can welding portion pressing device 120 is provided along the direction orthogonal to the conveying direction 111 and functions as a support. As an example of the fulfillment, the support arm 121 is extended so that the transport path 1 is
A drum can welding part pressing device 120-1 is installed on the left side of the conveyance direction 111 with the 13 in between, and a drum can welding part pressing device 120-2 is installed on the right side. Such a drum can welding portion pressing device 120 presses the welding portion 201 of the drum can body portion 200.

The detailed structure of the transfer device 130 will be described below. In the present embodiment, the transfer device 130 has the drum can body portion 200 which has been transferred through the transfer path 113.
To a drum can welding part pressing device, for example, a drum can welding part pressing device 120-1, and the drum can body part 200 after the flattening of the welding part is finished, and the other drum can welding part pressing device, for example, a drum can welding part. Pressing device 12
It is a device that is separated from 0-2 and is returned to the transport path 113.

The structure of the drum can welding portion pressing device 120 will be described. As described above, in the present embodiment, two drum can welding portion pressing devices 120-1 and 120-2 are provided, but since the structures of both are the same, the same components are designated by the same reference numerals, The drum can welding portion pressing device 120 will be described as a representative of the drum can welding portion pressing device 120-1. As shown in FIG. 1, the drum can welding portion pressing device 120-1 includes a base portion 12
7, a column 128 that is erected at one end of the base 127, and a support arm 121 that extends from the column 128 in parallel with and facing the base 127. Base part 127, column part 128, and support arm 1
21 forms a “U” -shaped outer shape. The drum can welding portion pressing device 120-1 generally includes the support arm 121, the pressing moving device 122, and the supporting member 123. The pressing movement device 122 is installed in a portion sandwiched by the support arm 121 and the base 127. As shown in FIG. 4, the support member 123 has the welding portion 2 in the circumferential direction of the drum can body portion 200.
01 is a member for supporting the drum body portion 200 on both the left and right sides of the welded portion 201 in the central portion, and is a member extending along the axial direction of the drum body portion 200. In addition, the support members 123 arranged on the left and right sides, respectively.
Since the drum can body portion 200 supported by the support member 123 can be smoothly moved in the axial direction,
Roller 123 rotatably supported by the support member 123
1 is provided in plural along the above-mentioned axial direction, and each roller 123
1 contacts the drum body portion 200. Such a supporting member 123 is installed in a common frame 161 provided in the lifting device 160 described later, and in the lifting device 160,
In the vertical direction, the common frame 161 has a descending height position 162,
By moving up and down between the rising position 163 and the supporting member 1,
23 also goes up and down.

Further, the support member 123 supports the drum can body portion 200 when the drum can body portion 200 is loaded on the support arm 121, and is arranged at a position corresponding to a position deviation prevention portion 1211 of the support arm 121 described later. To be done. Further, as will be described later, in the present embodiment, since the drum can body portion 200 is held by the suction pad 1215 provided in the misregistration prevention portion 1211, the support member 123 and the misregistration prevention portion 1211 are located at positions corresponding to each other. By being arranged, the drum can body portion 200 during the period from the loading to the pressing operation of the welding portion 201.
The support member 1 also has a function of preventing the positional displacement of the
23 has.

The support arm 121 is inserted inside the drum can body portion 200, has a length extending along the welded portion 201 and penetrates the drum can body portion 200, and has a substantially oval cross section. It is a member made of steel,
As will be described later, the welded portion 2 by the press moving device 122.
It has a pressure receiving member 1212 that comes into contact with the welded portion 201 during the crushing operation of 01. The pressure receiving member 1212 extends over the entire length of the welded portion 201 along the axial direction of the drum can body portion 200, and at the same time, the drum can body portion 200.
In the circumferential direction of the drum can body along the inner circumferential surface of the drum body portion 200 and covers at least the welded portion 201. Further, the support arm 121 has two position deviation prevention portions 1211 as shown in FIG. The position shift prevention portion 1211
In the circumferential direction of the drum can body portion 200, the drum can body portion 2 is sandwiched between the pressure receiving members 1212, and at least to a position facing the respective support members 123.
It is formed by extending the support arm 121 along the inner peripheral surface 202 of 00, and holds the drum can body portion 200 during the crushing operation and prevents displacement.
Therefore, during the crushing operation, the drum can body portion 20
0 does not become unstable, and the pressing moving device 122
With respect to a pressing roll 1221 described later, the welding portion 201 can be accurately pressed without causing a positional deviation.

The cross-sectional shape of the support arm 121 is a substantially oval shape as shown in FIG. 4 in this embodiment, but is not limited to this shape. That is, the rigidity enough to endure the crushing operation and the position deviation prevention portion 1211.
Any shape may be used.

Further, in the support arm 121 of this embodiment,
Pressure receiving member 12 that is a portion against which the welded portion 201 is pressed
The width dimension along the circumferential direction in 12 is equal to or larger than the width dimension of the pressing roller 1221 described later. Such a pressure receiving member 1212 has a diameter slightly smaller than the inner diameter of the drum can body portion 200, is attachable to and detachable from the support arm body portion 1213, and is attached to the body portion 1213 by a bolt 1214, for example. Therefore, when the pressure receiving member 1212 is deformed due to aging or the like, for example, only the pressure receiving member 1212 can be replaced.

Further, in the support arm 121 of this embodiment,
At the time of the crushing operation, each position deviation prevention part 1211 has an electromagnet-type suction pad 1 so that the position deviation prevention part 1211 holds the drum can body portion 200.
215 is buried. An exciter 1216 that excites and deenergizes the electromagnet is connected to the electromagnet provided on each suction pad 1215, and the exciter 1216 is controlled in operation by the controller 180. The suction pad 12
Reference numeral 15 is not limited to the structure having the above-mentioned electromagnet, and the position shift prevention portion 1 is provided during the crushing operation.
Any structure may be used as long as it can hold the drum can body portion 200 by the suction pad 1215 of 211, for example, a structure for performing a suction operation. In this case, a suction device is provided instead of the excitation device 1216.

Next, the pressing moving device 122 will be described. The pressing moving device 122 is provided in the drum can body portion 20.
0 of the drum can body portion 200 while being opposed to the support arm 121 so as to sandwich the welded portion 201, and pressing the welded portion 201 against the support arm 121 during the crushing operation of the welded portion 201. A device that moves along the direction to flatten the welded portion 201 by crushing the welded portion 201. The pressing roller 1221, the pressing device 1222, the guide member 1223, the traveling carriage 1224, and the traveling carriage moving device 1225. Equipped with. These components will be described below. However, by adopting the following configuration, the configuration relating to the pressing of the welded portion 201 is different from the configuration for holding and moving the long slider 8 as in the conventional device. Can be simplified and made compact, the occurrence of failures can be reduced, and the degree of freedom in designing the specifications of the pressing movement device 122 can be improved.

As shown in FIG. 3, the pressing roller 122 is
Reference numeral 1 denotes a steel roller that comes into contact with the welded portion 201 and crushes the welded portion 201. In the present embodiment, the roller has a diameter of φ.
The size is 150 mm and the width is 50 mm. Further, the peripheral surface of the pressing roller 1221 that comes into contact with the welded portion 201 is
It is possible to adopt various forms such as a flat shape parallel to the axial direction of the pressing roller 1221, a slightly drum-like raised shape, or conversely a slight concave shape, and surface hardening treatment. Has been applied. When the drum-like raised shape is adopted, a load can be intensively applied to the welded portion 201 of the drum can body portion 200 with a lower pressing force than in the flat case or the concave case. The same effect as those can be obtained. In the recessed form, the peripheral surface of the pressing roller 1221 is a curved surface having a radius dimension slightly larger than the radius dimension of the outer peripheral surface of the drum can body portion 200. When such a concave shape is adopted, the drum member body portion 200 is attached to the support member 123.
Even when the welded portion 201 of the drum can body portion 200 is slightly deviated in the circumferential direction of the drum can body portion 200 with respect to the vertical direction when compared with the drum-shaped body, the pressing roller is different from the case of the drum shape. 1221 can surely crush the welded portion 201. Further, when the flat form is adopted, an intermediate action and effect of the drum-like form and the recessed form can be obtained.

The pressing roller 1221 as described above is rotatably attached to the bearing member 12211. still,
Even if the drum-shaped peripheral surface is taken, since the width dimension of the pressing roller 1221 is larger than the width dimension of the welded portion 201, the pressing roller 1221 is actually
Not only the welded portion 201 but also both side portions of the welded portion 201 can be pressed along the circumferential direction of the drum can body portion 200. The pressurizing device 1222 generates a pressing force for pressing the pressing roller 1221 along the diametrical direction of the drum can body portion 200 against the welding portion 201 of the drum can body portion 200 loaded on the support arm 121. This device has a hydraulic cylinder in the present embodiment, and a maximum load of 10 tons can be applied to the pressing roller 1221 by the operation control of the control device 180. Instead of the hydraulic cylinder, a pneumatic cylinder or an electric cylinder can be used.

The guide member 1223 is provided on the base 127 of the drum can welding portion pressing device 120-1.
7, a guide member 1223-1 and a guide member 1223-2 laid parallel to each other along the axial direction of the drum can body portion 200 mounted on the support arm 121, and a guide member 1223. -1 and a guide member 122 provided on the base 127 in parallel with each other.
3-3 and a guide member 1223-4 which is provided on the base 127 in parallel with and facing the guide member 1223-2. The guide member 1223 is the following traveling carriage 12
The traveling carriage 1 so that 24 can move along the axial direction.
224 movement guidance.

The traveling carriage 1224 has the bearing member 12211 to which the pressing roller 1221 is attached.
And a main body 12242 equipped with the pressurizing device 1222.
And a wheel 12241 rotatably attached to the main body 12242 and engaged with the guide member 1223. The bearing member 12211 is vertically movable by a pressurizing device 1222 while being supported by the main body 12242. Traveling vehicle 12 having such a configuration
24 is a drum can body portion 20 attached to the support arm 121.
In the state where 0 is loaded, the pressing roller 1221 facing the welding portion 201 is moved to the pressing device 1222.
While pressing the welded portion 201 with the guide member 1223 engaged with the wheel 12241, the welded portion 201 is guided.
Move along.

The traveling vehicle moving device 1225 is a device for moving the traveling vehicle 1224 along the axial direction of the drum can body portion 200 so that the pressing roller 1221 can move along the welding portion 201. In the present embodiment, the hydraulic cylinder whose operation is controlled by the control device 180 corresponds to the traveling vehicle moving device 1225. The hydraulic cylinder is fixed to a mount 170 installed below the transport path 113 of the drum can body portion 200 transported by the transport device 110, and the drive shaft 1 of the hydraulic cylinder is fixed.
The end of 2251 is attached to the main body 122 of the traveling carriage 1224.
It is connected to 42. Therefore, due to the expansion and contraction of the drive shaft 12251 of the hydraulic cylinder, the traveling carriage 1224 moves along the axial direction. Instead of the hydraulic cylinder, a pneumatic cylinder or an electric cylinder can be used.

Next, an elevating device 160 for vertically moving the support member 123 will be described. As described above, in the present embodiment, the support arm 121 included in the drum can welding portion pressing device 120 extends along the direction orthogonal to the transport direction 111, and the transport path 113 is sandwiched between the transport arms 113 for transport. The drum can welding portion pressing device 120-1 is on the left side of the direction 111, and the drum can welding portion pressing device 12 is on the right side.
0-2 is installed. Therefore, the lifting device 160 in the present embodiment is the drum can welding portion pressing device 120-1.
And the drum can welding portion pressing devices 120-1 and 120-2 provided in the drum can welding portion pressing device 120-2 and the transport path 113.
At the same time, the carrier body supporting member 124, on which the drum can body portion 200 is mounted, which has reached the transfer location 114 corresponding to the installation position of 0-2, is moved up and down. With such a configuration, the lifting device 160 according to the present embodiment, as shown in FIG.
A common frame 161 on which the respective support members 123 and the carrier body support member 124 are installed, and an elevating cylinder 164 for vertically moving the common frame 161 between the descending height position 162 and the ascending height position 163. , The common frame 161
And a guide rod 165 for guiding the vertical movement of the.

Here, the lowered height position 162 is such that the drum can body portion 200 can be conveyed along the conveyance path 113 without interfering with the conveyance body support member 124 during conveyance by the conveyance device 110. This is the height position of the common frame 161 when the body support member 124 is lowered. The ascending height position 163 positions the carrier body support member 124 and the support member 123 to such an extent that the drum can body part 200 can be transferred between the drum can weld portion pressing device 120 and the carrier path 113. It is the height position of the common frame 161 when it is raised. When the drum can body portion 200 is placed at the elevated height position 163 and loaded on the support arm 121, the welded portion 201 of the drum can body portion 200 is attached to the support arm 121.
Placed as close as possible to almost contact.

The lifting cylinder 164 has a common frame 161.
One is arranged in the central part of the
The lift cylinders 164 are installed at four places surrounding the lift cylinder 164, and the lift cylinders 164 are fixed to the mount 170,
The guide rod 165 is attached to the gantry 170 so as to be vertically expandable and contractible. The common frame 16
1 is configured so as not to interfere with the pressing movement device 122 due to the movement of the common frame 161 due to lifting and lowering. Further, although the lift cylinder 164 uses a hydraulic cylinder whose operation is controlled by the controller 180 in the present embodiment, the lift cylinder 164 is not limited to this, and a pneumatic cylinder or an electric cylinder may be used. You can also

Next, the transfer device 130 will be described. As described above, the transfer device 130 loads the drum can body portion 200 into the drum can welding portion pressing device 120 from the transport path 113 or the drum can welding portion pressing device 120.
This device is a device that is detached from and returned to the transport path 113, and in this embodiment, as shown in FIGS. 1 and 2, includes a claw portion 133, a guide 131, and a drive cylinder 132 as a drive source. The guide 131 includes two drum can welding portion pressing devices 120-1 and 120-2 which are installed to face each other.
The upper part of the direction of extension of each support arm 121,
That is, it is installed along the axial direction of the drum can body portion 200 so as to straddle the conveyance path 113, and slidably supports the claw portion 133 in a suspended state. The drive cylinder 132 is an air cylinder in this embodiment, and the claw portion 13 is formed by expansion and contraction of the output shaft 1321 of the air cylinder.
3 is moved along the guide 131 in the axial direction. The operation of the drive cylinder 132 is controlled by the controller 180. The drive cylinder 132 is not limited to the air cylinder, and may be a hydraulic cylinder or an electric cylinder. The claw portion 133 has a claw member 1331 and, as shown in FIG. 1, when two drum can body portions 200 are arranged in series along the axial direction of the drum can body portion 200, the shafts of the drum can body portions 200 are arranged. The claw members 1331 are provided one at each end in the direction. That is, in the present embodiment, as shown in the figure, the three claw members 1331 are provided at a pitch slightly exceeding the entire length of the drum can body portion 200, and these three claw members 133 are provided.
The claw portion 133 that integrally configures 1 is the drive cylinder 132.
Is driven in the axial direction.

Further, the claw member 1331 is used for the lifting device 16
When the common frame 161 is arranged at the ascending height position 163 at 0, it is possible to interfere with the axial end of the drum can body part 200 at the upper part of the drum can body part 200. Therefore, in the state where the interference is possible, the claw portion 133 is moved in the axial direction by the operation of the drive cylinder 132, so that, for example, the roller 1231 of the transport body support member 124 installed in the transport path 113. The drum can body portion 200 supported above is moved and loaded on the support arm 121 of the drum can welding portion pressing device 120-1. More specifically with reference to the state shown in FIG. 1, the claw portion 133 is moved to the drum can welding portion pressing device 120-2 side by the operation of the drive cylinder 132, so that the roller of the carrier body supporting member 124 is rotated. Drum body part 2 existing on the transport path 113, which is supported on 1231
00-2 is loaded on the support arm 121 of the drum can welding portion pressing device 120-2. Further, since the three claw members 1331 are provided as described above, at the same time as the loading operation, the drum can body portion 200-1 loaded on the support arm 121 of the drum can welding part pressing device 120-1 is drum can welded. It is detached from the section pressing device 120-1 and transferred onto the carrier body support member 124 of the above-mentioned carrier path 113.
After that, by performing such an operation, the drum can body portion 200 can be continuously loaded and unloaded from the drum can welding portion pressing device 120.

The operation of the drum can manufacturing apparatus and the drum can welding portion pressing device of the present embodiment having the above-mentioned structure will be described below. The following operation control is executed under the control of the control device 180. As shown in FIG. 2, each drum can body portion 200 in which the welding portion 201 is positioned in the gravity direction by gravity causes the transport device 110 to transport the transport path 113 in the transport direction 11 as shown in FIG.
1 is conveyed to the transfer place 114 one by one.
The drum can body portion 200 that has reached the transfer location 114
-1 stops. Next, the lifting device 160 operates,
The elevating cylinder 164 raises the common frame 161 from the lowered height position 162 to the raised height position 163. Along with this, the rollers 1231 of the carrier body supporting member 124 come into contact with the outer surface of the drum can body portion 200-1, and the drum can body portion 200-1 is supported by the carrier body supporting member 124 and rises.

After the common frame 161 reaches the elevated height position 163, the transfer device 130 operates. Therefore, the claw member 1
331 abuts the axial end of the drum can body portion 200-1, and the drum can body portion 200-1 moves on the roller 1231 of the support member 124 for the transport body and the support member 123 of the drum can welding portion pressing device 120-1. Drum can body part 2
It moves to the direction of the arrow 150 shown in FIG. 6 in the axial direction of 0-1, and is loaded on the support arm 121 of the drum can welding portion pressing device 120-1.

Drum can body portion 200-1 loaded on the support arm 121 of the drum can welding portion pressing device 120-1.
Are held on the lower surface of the support arm 121 by the excitation of an electromagnet-type suction pad 1215 provided on the misalignment prevention portion 1211 of the support arm 121. When the drum can body portion 200-1 is held by the support arm 121, the common frame 161 is lowered to the lowered height position 162 by the operation of the elevating device 160, and the support member 123 and the carrier body support member 124 are also moved. Go down. After the holding, the pressing moving device 12
2 works. That is, the pressing roller 1221 of the pressing movement device 122 arranged at the axial end portion of the drum can body portion 200-1 is pressed by the operation of the pressure device 1222 against the welding portion 201 of the drum can body portion 200-1, and the support arm While crushing the welded portion 201 and removing the oxide scale with 121, the moving device 1225 for the traveling carriage of the pressing moving device 122 drives the welded portion 201 to move along the welded portion 201 in the axial direction of the drum can body portion 200-1. .

As described above, in this embodiment, as a post-process of the pressing operation by the drum can welding part pressing device 120, the welding part 2 along the axial direction of the drum can body portion 200 is welded.
Since both ends of 01 are flattened by the mash cutter device 301, the pressing operation by the pressing roller 1221 is unnecessary. Therefore, the length by which the pressing roller 1221 actually presses the welded portion 201 is the length excluding the both ends of the welded portion 201. In this embodiment, the lengths of the both ends are about 20 mm from the end surface of the drum body portion 200 to the inside.

In this embodiment, the pressing roller 1221
The range of pressing with only the drum body 200
It is set so as to be in the central part range of the drum can body part 200 by removing about 35 mm from both end surfaces to the inside. The value of 35 mm is determined for the following reasons. That is, when the entire length of the welded portion 201 is pressed only by the pressing roller 1221 without using the mash cutter device 301, as can be inferred from FIGS. 17 and 18, the welded portion is thinned up to about 15 mm from the can end. Occurs. Therefore, at least 15 mm from the can end is the mash cutter device 3
It is considered that the pressing operation by 01 is necessary, and further, the positioning accuracy of the pressing roller 1221 and the mash cutter device 301
The above value was determined in consideration of the overlap area between the pressing operation range by the pressure roller 1221 and the pressing operation range by the pressing roller 1221. Therefore, about 20 mm to about 35 mm
The range up to corresponds to the overlap area.
Further, in the present embodiment, when the material thickness of the drum body 200 is 1 mm, the mash cutter device 301 is
At both ends of the drum can body portion 200, the pressing force is controlled so that the thickness of the welded portion 201 from the can end to the position of 35 mm is 1.15 mm.
The pressing roller 1221 that presses the central portion of the welded portion 201 excluding these ends is controlled in pressing force so that the thickness of the welded portion 201 is 1.25 mm.

Further, as described above, the both ends are pressed by the pressing roller 1.
Not pressing with 221 also produces the following effect. That is,
When the pressure rollers 1221 are also used to press the both ends, the drum can body portion 20 is pressed by the pressure rollers 1221.
The pressing roller 1221 must maintain the loaded state before the pressing of 0 and at the end of the pressing. Therefore, even if the pressure roller 1221 is to be bitten into one end of the welded portion 201 under a load, it is difficult to bite it first, and it is not possible to bite it and the drum can body portion moves with the movement of the pressure roller 1221. There is a possibility that 200 will be moved in the axial direction. Further, the pressing roll 1221 is easily scratched. On the other hand, from the other end of the welded portion 201 with the load applied, the pressing roller 122
1 is removed, the pressing roller 1221 causes the welding portion 201
When the drum can body portion 200 is disengaged, the drum can body portion 200 may move in a direction opposite to the direction in which the pressing roller 1221 travels, which may interfere with the next operation of the drum can body portion 200. In addition, the pressing roller 1221 is welded to the welded portion 2
When it is disengaged from 01, the pressing roll 1221 collides with the support arm 121, and thus both are easily scratched, and it is also considered that fatigue of the support arm 121 and the like is accelerated by repeating the collision. There is also a problem that the strength design of the support arm and the like must be increased more than necessary.

FIG. 15 shows a case in which the end of the welded portion 201 having a material thickness of the drum can body portion 200 of 1.0 mm is pressed by the mash cutter device 301 and pressed by the pressing roll 1221 while being bitten. And indicate the plate thickness distribution of the welded portion 201. As shown in FIG. 4, the welded portion 201 has a thickness of about 1.6 mm because the above-mentioned materials overlap each other. As is clear from FIG. 15, when the mash cutter device 301 is used, almost no thinning of the plate thickness is observed, whereas in the case of the pressing roll 1221, the thickness is over a range of several mm from the can end. It becomes thin. In addition, as described above, the mash cutter device 301 is used for the welding portion 20.
Although the pressing force is controlled so that the thickness of No. 1 is 1.15 mm, the mash cutter device 301 has a thickness of 1.15 mm or less within a range of several mm from the can end in FIG. It is formed by the welding operation, not by the pressing force of. As described above, by pressing both ends of the welded portions 201 located at both ends of the drum can body portion 200 with the mash cutter device 301, it is possible to prevent the welded portion 201 from being overthinned. Therefore, the mechanical properties of the both ends of the welded portion 201 can be improved. Specifically, deterioration prevention in flange processing for the both ends of the welded portion 201, prevention of deterioration of deformability due to work hardening, and minuteness of the welded portion 201 can be improved. It is possible to prevent the occurrence of cracks. Further, in the test conducted by the applicant, when the flange processing is applied to both ends of the two types of drum can body portions 200 for which the data shown in FIG. The case of pressing while biting reached three times that in the case of using the mash cutter device 301.

As described above, in this embodiment, the support arm 121 is provided with the displacement prevention portion 1211, and the displacement prevention portion 1211 is further provided with the suction pad 1215 so that the drum can body portion 20 is provided on the lower surface of the support arm 121.
Since 0 is held, the pressing movement device 122
During the pressing operation of the welded portion 201 due to, the drum can body portion 200 is not displaced. Therefore, it becomes possible to press the welded portion 201 accurately and stably by the pressing roller 1221. By holding the drum can body portion by holding it by the suction pad 1215, the drum can body portion 200 can be prevented from being deformed as compared with the conventional case in which the drum can body portion is sandwiched and held from both ends.

Further, in this embodiment, the support arm 12 fixed to the column portion 128 of the drum can welding portion pressing device 120.
1 is disposed inside the drum can body portion 200, and the welding portion 201 is pressed by the pressing roller 1221 against the support arm 121 from the outside of the drum can body portion 200. As compared with the structure in which the pressing device is provided at the tip end of the welding part 201, the rigidity of the part involved in the pressing operation of the welded part 201 is higher than in the conventional case. Therefore, the followability of the change in, for example, the crushed amount of the welded portion 201 with respect to the change in the pressing force by the pressing roller 1221 is better than in the conventional case, so that the pressing force by the pressing roller 1221 is easier to control than in the conventional case.

On the other hand, in parallel with the pressing operation by the pressing moving device 122, before the pressing operation is completed, as shown in FIG. 7, the conveying device 110 is operated to move the next drum can body portion 200-. 2 is carried into the transfer place 114 of the transport path 113. After the pressing operation by the pressing movement device 122 is completed, the common frame 161 is again moved up to the elevated height position 163 by the operation of the elevating device 160.
Therefore, the drum can body portion 200-2 arranged at the transfer place 114 is lifted by the transport body support member 124, and the roller 1231 of the support member 123 again approaches the outer surface of the drum can body portion 200-1. Support member 123
After the roller 1231 of No. 1 approaches the outer surface of the drum can body portion 200-1 again, the excitation of the suction pad 1215 is released, and the drum can body portion 200-1 is supported on the roller 1231 of the support member 123.

After the common frame 161 reaches the elevated height position 163, the transfer device 130 operates. Therefore, the claw member 1
331 abuts on the respective axial ends of the drum can body portion 200-1 and the drum can body portion 200-2. The drum can body portion 200-1 is on the support member 123 of the drum can welding portion pressing device 120-1 and the roller 1231 of the transport body support member 124 in the axial direction of the drum can body portion 200-1 and is shown in FIG. Arrow 151
To the drum can welding portion pressing device 120-1.
It is transferred from the support arm 121 of FIG. On the other hand, the drum can body portion 200-2 is moved in parallel with the transfer operation of the drum can body portion 200-1, and the roller 123
1 in the direction of the arrow 151, and the conveying path 113
Support arm 1 of drum can welding part pressing device 120-2
21 is loaded.

The drum can body portion 200-2 loaded on the support arm 121 of the drum can welding portion pressing device 120-2.
On the other hand, in the case where the holding operation by the suction pad 1215, the pressing operation by the pressing movement device 122, and the holding operation release of the suction pad 1215 performed on the drum can body portion 200-1 are performed on the drum can body portion 200-1. The same is executed as. Further, as shown in FIG. 9, the operation for arranging the next drum can body portion 200-3 at the transfer place 114 is also executed in the same manner as described above.

In this way, each drum can body portion 200
On the other hand, the pressing operation of the welding portion 201 is continuously executed. Incidentally, the drum can body portion 20 subjected to the pressing operation
0 is transported by the transport device 110 to the device that executes the next step.

In this embodiment, as shown in FIG. 5 and the like, the drum can body portion 20 extends in a direction orthogonal to the transport direction 111.
Although the drum can body portion 200 is configured to be conveyed with the axial direction of 0 directed, the drum can body portion 200 may be conveyed with the conveying direction 111 and the axial direction parallel to each other. In this case, when the drum can welding portion pressing device 120 is arranged along the direction orthogonal to the transport direction 111 as in the above-described embodiment, the drum can body portion 20.
In order to attach 0 to the drum can welding portion pressing device 120,
A device for changing the axial direction of the drum body portion 200 from the transport direction 111 to the above orthogonal direction is required. On the other hand, FIG.
As shown in FIG. 1, if the drum can welding portion pressing device 120 is arranged in parallel with the transport direction 111, such a changing device is unnecessary.

Further, in this embodiment, as shown in FIG. 1 and the like, two drum can welding portion pressing devices 120-1 and 120 are used.
-2 is provided to reduce the time required to process one drum can body portion 200.
You may provide only a stand.

Further, in this embodiment, the support arm 12 is
Although the drum can body portion 200 was held by using the suction pad 1215 with respect to the position shift prevention portion 1211 of No. 1, the steel plate of the drum can body portion 200 was pressed against the position shift prevention portion 1211 from the outside of the drum can body portion 200. It can also be configured by using, for example, a clamp device so as to hold it.

In the present embodiment, the carrying direction 111
The mash cutter device 301 is arranged on the post-process side of the drum can welding portion pressing device 120 along the above. However, the drum can welding portion pressing device 120 is
Since both end portions of No. 1 are not pressed and only the central portion is pressed, the protruding portion is not generated by the pressing operation of the drum can welding portion pressing device 120. Therefore, in the present embodiment, there is no problem before and after each operation of the drum can welding portion pressing device 120 and the mash cutter device 301. Therefore, as shown in FIG. 12, the mash cutter device 301 can be arranged on the pre-process side of the drum can welding portion pressing device 120. As described above, in the present embodiment, the order of steps is not fixed unlike in the conventional case, and the degree of freedom in machine layout in the manufacturing line is higher than in the conventional case.

[0057]

As described above in detail, according to the drum can welding portion pressing device of the first aspect and the drum can manufacturing device of the second aspect of the present invention, by providing the support having the position deviation preventing portion, During the pressing operation of the welding portion, the drum can body portion is held on the support body without being displaced. Therefore,
The welded portion can be pressed accurately.

According to the drum can welding portion pressing method of the third aspect of the present invention, the roll is moved and crushed about the central portion of the welding portion, and both ends of the welding portion excluding the central portion are treated as described above. By sandwiching and pressing the both ends along the thickness direction of the welded portion to crush them, it is possible to prevent the thickness of the both ends from becoming too thin. Therefore, the mechanical properties of the both ends can be improved as compared with the conventional case.

[Brief description of drawings]

FIG. 1 is a front view of a drum can welding portion pressing device according to an embodiment of the present invention.

FIG. 2 is a side view of the drum can welding portion pressing device shown in FIG. 1, including a partial cross section thereof.

FIG. 3 is a view mainly for explaining a pressing moving device portion provided in the drum can welding portion pressing device shown in FIG. 1, and is a cross-sectional view of the pressing moving device.

FIG. 4 is a view mainly for explaining a support arm portion provided in the drum can welding portion pressing device shown in FIG. 1, and is a cross-sectional view of the support arm portion.

5 is a plan view showing an arrangement portion of the drum can welding portion pressing device shown in FIG. 1 in the drum can manufacturing device according to the embodiment of the present invention, and is a diagram for explaining the operation of the drum can manufacturing device. FIG. .

FIG. 6 is a diagram for explaining the operation of the drum can manufacturing apparatus, and is a diagram showing the next operation of the operation shown in FIG. 5.

FIG. 7 is a diagram for explaining the operation of the drum can manufacturing apparatus, and is a diagram showing the next operation of the operation shown in FIG. 6.

FIG. 8 is a diagram for explaining the operation of the drum can manufacturing apparatus, and is a diagram showing the next operation of the operation shown in FIG. 7.

FIG. 9 is a diagram for explaining the operation of the drum can manufacturing apparatus, and is a diagram showing the next operation of the operation shown in FIG. 8.

10 is a perspective view of a drum can body portion where a welded portion is pressed by the drum can welding portion pressing device shown in FIG.

FIG. 11 is a plan view of a modified example of the drum can manufacturing apparatus shown in FIG.

FIG. 12 is a drum can welding portion pressing device shown in FIG. 1 and FIG.
It is a figure which shows the arrangement | positioning relationship with the mash cutter apparatus shown in FIG.

FIG. 13 is an overall view of a mash cutter device provided in the drum can manufacturing device according to the embodiment of the present invention.

14 is an enlarged view of a press device portion and a cutting device portion in the mash cutter device shown in FIG.

FIG. 15 is a graph showing a change in thickness of both ends of the welded part when the welded part is pressed only by the pressing roller and when both ends of the welded part are pressed by the mash cutter device.

FIG. 16 is a perspective view of a conventional weld portion shaping device.

FIG. 17 is a graph showing a change in the thickness of the welded portion when the pressure roller is pressed while biting into the end portion of the welded portion.

FIG. 18 is a graph showing changes in the thickness of the welded portion when the pressure roller is disengaged from the end of the welded portion while pressing the welded portion with the pressure roller.

[Explanation of symbols]

101 ... Drum can manufacturing apparatus, 110 ... Conveying apparatus, 111
... conveyance direction, 113 ... conveyance path, 120 ... drum can welding portion pressing device, 121 ... support arm, 122 ... pressing moving device, 123 ... supporting member, 124 ... conveying body supporting member,
130 ... Transfer device, 200 ... Drum can body part, 201
… Welded part, 301… Mash cutter device.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-9-300032 (JP, A) JP-A-8-323438 (JP, A) JP-A-7-16680 (JP, A) JP-A-4- 33954 (JP, A) JP 62-254938 (JP, A) Actual development 64-15632 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) B21D 51/18 B21D 51 / 26 B21D 51/30 B23K 31/00 B23K 37/08 B65D 1/16

Claims (10)

(57) [Claims] 1. A drum can body portion before attachment of a base plate and a top plate, which is produced by welding both side ends of the steel plate extending in the axial direction of the cylinder in a cylindrical body formed by bending a steel plate to each other ( 200) is a drum can welding part pressing device for crushing the weld parts (201) at the both ends, and a support (12) to be inserted inside the drum can body part.
1), which extends over the entire length of the weld along the axial direction and extends along the inner peripheral surface of the drum can body portion in the circumferential direction of the drum can body portion, and at least the weld portion is formed. The cover has a pressure receiving portion (1212) that comes into contact with the welded portion when the welded portion is crushed,
A position deviation prevention portion (1211) which is located on both sides of the pressure receiving portion in the circumferential direction and which prevents the drum can body portion from being displaced during the crushing operation.
And a support body (121) having the above-mentioned support body (121) facing the support body so as to sandwich the welded portion on the outside of the drum can body portion. A drum can welding part pressing device comprising: a pressing moving device (122) that moves in the axial direction while pressing to crush the welding part to flatten it. 2. The drum can welding portion pressing device according to claim 1, wherein the misregistration prevention portion has a suction device (1215) for sucking and holding the drum can body portion. 3. The drum can body part is supported when the drum can body part is loaded on the support body, and the drum can body part is disposed at a position corresponding to the misregistration prevention part and the crushing operation of the welding part is performed from the loading. The drum can welding portion pressing device according to claim 1 or 2, further comprising a support member (123) for preventing a positional displacement of the drum can body portion during its reaching. 4. The drum can welding portion according to claim 1, wherein the pressing movement device performs the crushing operation on a central portion of the welding portion along the axial direction in the axial direction. Pressing device. 5. A transport device (110) for sequentially transporting a plurality of drum can body portions (200) in the transport direction along a transport path, and a transport device (110) disposed on both sides of the transport path, respectively. The two drum can welding portion pressing devices (120-1, 120-2) according to any one of claims 1 to 3, and the drum can welding portion pressing device that has been conveyed by the conveying device. A transfer device for mounting the drum can body part on one of the drum can welding part pressing devices and at the same time detaching the drum can body part after the flattening of the welding part from the other drum can welding part pressing device and returning it to the transport path. (130) and the drum can manufacturing apparatus characterized by including these. 6. The drum can manufacturing apparatus according to claim 5, wherein the drum can welding portion pressing device performs a crushing operation on a central portion of the welding portion along the axial direction of the drum can body portion in the axial direction. 7. The drum can welding portion pressing device is disposed on the front side or the rear side of the drum, and is located at both axial end portions of the drum can body portion excluding the central portion of the weld portion in the axial direction. 7. The drum can manufacturing according to claim 6, further comprising an end pressing device (301) that clamps and presses both ends of the welded portion along a thickness direction of the welded portion to perform a crushing operation of the both end portions. apparatus. 8. A drum can body portion before attachment of a base plate and a top plate, which is produced by welding both end portions of the steel plate extending in the axial direction of the cylinder in a cylindrical body formed by bending a steel plate to each other ( 200) is a drum can welding part pressing method of crushing the welding parts (201) at both end portions, wherein a center part of the welding part in the axial direction of the drum can body part is rolled along the axial direction. Crushing by moving, both ends of the welded portion located at both ends in the axial direction of the drum can body portion excluding the central portion are clamped by pressing the both ends along the thickness direction of the welded portion. A method for pressing a welded portion of a drum can, which is characterized by performing a crushing operation. 9. The method for pressing a welded portion of a drum according to claim 8, wherein the crushing operation for the both end portions is performed before the crushing operation for the central portion. 10. The method for pressing a drum can welded portion according to claim 8, wherein the crushing operation on the central portion is performed before the crushing operation on the both end portions.