JPH1128524A - Forming method for large-sized corrugated steel plate and its forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent material from restoring without wasting the power of a press by specifying a pad pressure for pressing within the range of bending force in the case of forming a large-sized corrugated steel plate respectively having the specified dimension of the pitch, the depth, the top part, the bottom part and the inclined part of a corrugation with the steel plate having the thickness of a specified dimensional range. SOLUTION: With respect to the preformed corrugated part of the interior part side in the carrying direction of the large-size corrugated steel plate 1, the function of the pre-pressed pad is fulfilled with the split upper die 33A projected downward by a gas spring 35 at the time of press working. In the case of 8-16 mm in plate thickness, 900-1800 mm in pitch of the corrugation, 150-300 mm in depth of the corrugation, 250-500 mm in top part, bottom part and inclined part of the corrugation respectively, the restoring of the material is prevented when the pad pressure is set within the range of 10-20% of bending force. The case incapable of preventing the restoring of the material is generated in the case of being lower than this range, while bending itself does not possibly go well in the case of the pad pressure being higher than this range.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a forming method and a forming apparatus for forming a large corrugated steel sheet by forming a large corrugated sheet into a large steel sheet.

[0002]

2. Description of the Related Art In general, in order to bend a steel sheet having a large thickness and a weight that is too large to be handled manually,
The steel plate is moved by a crane, and is bent using a processing machine having a V-shaped dedicated V-shaped mold called a press brake (or arrow type).

For example, when a steel plate is bent into a trapezoidal waveform, four portions of the trapezoid are each V-bent sequentially by a press brake. In each of the four bending operations, each time the bending operation is performed, the steel plate is suspended by, for example, a hoist crane, moved out of the press operation area of the press brake, and a part of the hoist crane is removed and inverted. Lift and move into the press operation area of the press brake.

[0004] However, bending a heavy steel plate with a press brake requires moving and reversing the steel plate almost every time bending is performed, which is cumbersome to handle and low in productivity. there were. Therefore, in order to facilitate the handling of the steel sheet and increase the productivity, it is conceivable to manufacture a special mold for a shape to be processed, instead of the press brake, and to perform bending using a large press machine.

When a plurality of waveforms are continuously formed one by one, at the time of press working, the material returns (becomes attracted) from the already processed part of the waveform on the back side in the transport direction, The waveform on the back side is deformed. Therefore, it is conceivable to provide a pad function to a part of the back side of the mold and press the back side of the steel plate in advance to prevent the material from returning.

[0006]

However, a press capable of bending a steel plate having a large thickness into a corrugated shape needs to be large and capable of producing a large force.
Such large presses are very expensive. Moreover, part of the power of the press must be used for the pad function.

Therefore, a pad device that partially uses the force of a press machine, for example, a spring device, can exert only a specific pressure, lacks flexibility, and wastes a large amount of pad pressure. . As a result, the force that can be used for the original press bending is reduced. Larger presses are needed to keep available power from becoming too small.

The present invention has been made in order to solve the above problems. For example, the number of gas springs and / or the pressure can be freely selected to maintain a minimum pad function and press bending. Since the processing force can be optimized to be small, the pad function can be exhibited without wasting the power of the press machine, material return can be prevented, and the press machine can be downsized. It is an object of the present invention to provide a method and apparatus for forming a large corrugated steel sheet that can be formed.

[0009]

Means for Solving the Problems In order to achieve the above object, a first invention is to form a large corrugated steel sheet having a plurality of large corrugations by bending a steel sheet. 8 to 1
6 mm, the pitch of the waveform is 900 to 1800 mm, the depth of the waveform is 150 to 300 mm, and the dimensions of the top, bottom, and inclined portions of the waveform are 250 to 500 mm, respectively. Using a press machine having an upper mold and a lower mold having two pitches, a step of conveying the steel sheet by one pitch to this press machine, and a waveform in which the upper mold and the lower mold for one pitch on the back side in the conveying direction are already processed. A pad step of pressing in advance, and a step of newly performing press bending of the upper die and lower die for one pitch on the front side in the transport direction in a state where the pressing is performed, and the pad pressure for pressing is 10% to 20% of bending force of press machine
% Of the large corrugated steel sheet.

[0010] The second invention is to form a large corrugated steel sheet having a plurality of large corrugations by bending a steel sheet, and to obtain a sheet thickness t of the steel sheet.
Is 8 to 16 mm and the pitch of the waveform is 900 to 1800 m
m, the depth of the waveform is 150 to 300 mm, and the top, bottom, and the slope of the waveform each have a dimension of 250 to 500 mm. Press machine, a conveying device that conveys the steel sheet by one pitch to the press machine, and one pitch for providing a pad function for previously pressing a waveform already processed by an upper die for one pitch on the back side in the conveying direction. A plurality of gas springs for supporting and protruding the upper mold for the number of the gas springs and / or the number of gas springs so that a pad pressure for pressing is 10% to 20% of a press bending force. This is a large corrugated steel sheet forming apparatus characterized by adjusting the pressure.

In a third aspect of the present invention, the transfer device further comprises:
A frame-shaped frame that surrounds a lower die and an upper die in a horizontal plane of a press machine that presses a steel plate, vertical moving means for vertically moving the frame, and a lower die and an upper die that reciprocate on the frame in a transport direction. A trolley that can be freely moved into and out of the press operation area, an electric magnet provided on the trolley to attract the steel plate, a carry-in conveyor connected to the carry-in side of the frame, and a carry-out side connected to the carry-out side of the frame. And an unloading conveyor.

A fourth invention is further characterized in that the carry-in conveyor or the carry-out conveyor is a roller conveyor,
This is a large corrugated steel sheet forming apparatus having an elevating device for raising and lowering a roller group constituting the whole or a part of the roller conveyor.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION

(Use of Large Corrugated Steel Sheet) First, as shown in FIG. 2, this large corrugated steel sheet 1 is for forming the side wall 5 of the bridge 3. Conventional bridge side walls were made of concrete (PC), but concrete is heavy and difficult to transport, so it is not suitable for bridges fixed in mountains, for example. It has been proposed to be used.

That is, the bridge 3 has a box-shaped cross section in which the upper concrete slab 7 and the lower concrete slab 9 are connected by the left and right side walls 5. Each floor slab 7, 9 is provided with an internal cable 11 inside the longitudinal direction for reinforcement. The box-shaped interior is divided by a bridge girder 13 at various points in the longitudinal direction, and an outer cable 15 connecting the bridge girder 13 passes through the box-shaped interior.

(Large corrugated steel sheet) Side wall 5 of such a bridge 3
FIG. 3 shows a state in which the large corrugated steel sheet 1 is shipped from the factory.

That is, a plurality of rebars 19 extending in the direction of the waves are welded to the large corrugated steel sheet 1 in which the large waveforms 17 are formed at 2 to 6 pitches (two pitches in the figure). Reinforcing bar 19
Is for improving the adhesion to the concrete slabs 7 and 9. In the figure, a reinforcing bar 19 to be welded to pass to the top of each wave and a reinforcing bar to be welded to pass to the bottom of the wave are arranged toward the direction of the wave, and at both ends in a direction perpendicular to the direction of the wave. Mounted in pairs. Further, a plurality of bolt holes 21 through which bolts for connecting to other large corrugated steel plates are formed are formed at both ends in the wave direction.

The large corrugated steel sheet 1 in such a shipping state is
In some cases, a plurality of large corrugated steel sheets are welded. Further, at the time of shipping, a predetermined surface finish is performed and a predetermined coating is applied.

FIG. 4 shows an example of the basic shape of the large corrugated steel sheet 1 before such surface finishing, painting, welding and the like. Further, as an example of the dimension, the pitch P of the waveform 17 is 1200 mm, the depth B of the wave is 200 mm, and the dimension L of the top, bottom, and slope of the wave is 330 mm. The plate thickness t is 9 mm. The length W and the width H of the entire large corrugated steel sheet 1 also differ depending on which part of the bridge the large corrugated steel sheet is used. However, the length W is a length at which the waveform 17 having the above dimensions can be formed at least two pitches.

(Pressing Machine) Next, in FIG. 5, a pressing machine 2 for pressing a flat steel sheet into a large corrugated steel sheet 1 will be described.
3 shows the front of FIG. The press machine 23 presses with a rated 2500 tons of force, and a lower mold 29 fixed to a lower mold holder 27 provided on the work floor 25 is fixed to an upper mold holder 31 that moves up and down. The mold 33 is fitted,
A waveform 17 for one pitch is formed on a steel plate (see FIG. 4).

(Upper mold and lower mold) In FIG.
9 shows a vertical cross-sectional view (a cross-sectional view cut in the transport direction, that is, the direction of the wave of a large waveform) in a state where the upper die 9 and the upper die 33 are fitted to each other. FIG. 10 shows a cross-sectional view.

The upper mold 33 is divided into two parts in the wave direction (transport direction). Of these, the divided upper mold 33A on the far side (right side in FIG. Attached via 35. That is, the divided upper mold 33A is supported on the distal end of the telescopic rod 37 projecting from the plurality of gas springs 35 embedded in the upper mold holder 31.

A support pin 39 embedded in the upper die holder 31 is slidably received in a pin hole 41 of the divided upper die 33A. The pin head 43 formed at the tip of the support pin 39 is engaged with the reduced-diameter portion at the upper end of the pin hole 41.
A has a structure in which it can protrude and retreat in the vertical direction in the range in which the support pin 39 and the pin hole 41 slide, and can be prevented from falling down.

The number of gas springs 35 and the gas pressure are such that the force (pad pressure) transmitted to the large corrugated steel sheet 1 through the split upper mold 33A is 10% to 20% of the press bending force.
%, For example, in the range of 100 to 300 tons.

With this structure, of the large-sized corrugated steel sheet 1 to be pressed, the already formed corrugated portion on the far side in the transport direction is divided by the gas spring 35 so as to protrude downward during the pressing. The pad function is performed by being pressed in advance by the upper mold 33A. Furthermore, upper mold holder 3
1 is lowered, so that the upper split die 33B on the front side in the transport direction is
As a result, the next waveform is bent. Thereby, it is possible to prevent the material of the back-side corrugated portion that has already been bent from flowing back to the near side.

According to the study of the inventor, the thickness of the steel sheet is 8 to
16 mm, the pitch of the waveform is 900 to 1800 mm, the depth of the waveform is 150 to 300 mm, and the dimensions of the top, bottom and slope of the waveform are 250 to 500 mm, respectively. If the pad pressure is set in the range of 10% to 20% of the processing force, specifically, in the range of 100 to 300 tons, the return of the material can be prevented, and at the pad pressure lower than this range, the return of the material can be prevented. It has been found that some cases cannot be prevented.

If the pad pressure is higher than this range, sufficient force for press bending is not left, and the bending itself may not be performed properly. That is, it was found that in this range, the pad function can be exerted without wasting the power of the press machine.

(Transporting Apparatus) Next, a transporting apparatus for transporting a steel sheet to the press machine 23 will be described with reference to FIGS.

A rectangular frame-like frame 45 (FIGS. 8 and 9) is arranged so as to surround a pressing operation area in which the upper die 33 moves up and down with respect to the lower die 29 (FIG. 7) to perform a pressing operation in a horizontal plane. Is done. The frame 45 protrudes farther inward in the transport direction (right side in FIG. 7) than the press operation area. To this protruding part, a trolley 4 described later
7 can be moved outside the press operation area.

The legs provided at four locations around the frame 45 are composed of synchro cylinders 49, each of which can operate synchronously.
It is operated by two helical gear motors 51 (FIGS. 8 and 9), and constitutes a vertically moving means for vertically moving the frame.

Rails 53 are provided on two sides provided in parallel to the left and right in the transport direction of the rectangular frame, and a plurality of wheels 55 are mounted on each rail 53 in the transport direction (right in FIG. 7). A carriage 47 that can reciprocate in the direction (direction) is arranged.

At the left and right ends of the carriage 47, a chain 57 is fixed to the rear end in the transport direction. The chain 57 is disposed above and parallel to the rail 53, and a chain sprocket 59 provided at the rear end of the rail 53. After being wound around the rail 53, it is arranged below the rail 53, is wound around a drive chain sprocket 61 provided at the leading end of the rail 53 in the transport direction, and passes over the rail 53 again and is fixed to the front end of the bogie 47. The drive chain sprocket 61 is driven by a helical bevel gear motor 63.

As described above, the driving force of the helical bevel gear motor 63 pulls the bogie 47 through the chain 57, and the bogie 47 reciprocates by changing the rotational direction of the driving, and moves into and out of the press operation area. can do. Electric magnets 65 are provided at four places on the lower surface of the carriage 47 to attract the flat part of the steel plate or the top part of the formed waveform.

A roller conveyor 67, which is a carry-in conveyor, is connected to the carry-in side (left side in FIG. 7) of the frame 45. A part of the roller group 68 (FIG. 8) at the center (right side in the figure) of the roller conveyor is moved from a normal position to a predetermined height (same as the height of the frame 45) by a cylinder which is a lifting device 69 (FIG. 7). ) Only the ascending operation is enabled.

On the carry-out side (the right side in FIG. 7) of the frame 45, a belt conveyor as the carry-out conveyor 71 is provided. In this belt conveyor, four ring-shaped belts 73 (FIG. 9) are respectively wound around a belt pulley 77 provided at the rear end of the conveyor frame 75 and a drive belt pulley 79 provided at the front end. Each belt 7
3 are arranged at equal intervals. The drive belt pulley 79 is driven to rotate by a helical bevel gear motor 81.

(Operation) The operation of this embodiment will be described below. The steel plate (not shown) is placed on the carry-in conveyor 67 and moved in the transport direction (rightward in FIG. 7).
The upper surface of the carry-in conveyor 67 and the upper surface of the lower mold 29 are located in the same plane. Therefore, when the movement is further continued and one pitch of the waveform is conveyed, the steel sheet is set on the lower mold 29. This setting is performed on the waveform portion on the front side in the transport direction in the lower mold 29. In this set state, the carriage 47 moves out of the press operation area (to the right end in FIG. 7).

Then, the upper die 33 descends to perform the first pressing operation. At this time, there is no already processed waveform, and the problem of material returning from the waveform does not occur.

Thereafter, the carriage 47 returns to the press operation area, and the frame 45 is moved by the action of the synchro cylinder 49.
, The electric magnet 65 of the carriage 47 attracts the steel plate, the frame 45 rises, and the carriage 47 moves in the transport direction (FIG. 7).
The steel plate is carried out by moving to the middle right direction.

Further, the frame 4
5 is lowered, the electric magnet 65 of the carriage 47 releases the attraction, and the portion of the waveform already formed on the steel plate is set with respect to the portion of the lower mold 29 that is on the far side in the transport direction. At the same time, the portion of the steel sheet where the next waveform is to be formed is set to the waveform portion on the near side of the lower mold 29. In this way, one pitch of the waveform is conveyed again.

Then, the upper die 33 descends to perform the second pressing operation. At this time, the already formed portion of the waveform on the far side in the transport direction is suppressed in advance by the split upper mold 33A protruded downward by the gas spring 35 during the press working, and the pad function is exhibited. Further, since the upper die holder 31 is lowered and the bending process is performed, it is possible to prevent the material of the already formed deep corrugated portion from flowing back to the near side.

Thereafter, the carriage 47 returns to the press operation area, and the frame 45 is moved by the action of the synchro cylinder 49.
Is lowered, and the electric magnet 65 of the carriage 47 attracts the top of the processed waveform, the frame 45 rises, and the carriage 47
Moves in the transport direction (right direction in FIG. 7), thereby carrying out the steel sheet that has become a large corrugated steel sheet. Further, the frame 45 descends with respect to the carry-out conveyor 71, the electric magnet 65 of the carriage 47 releases the suction, and passes the carrier to the carry-out conveyor 71.

In the above steps, the amount of rise of the frame 45 is
It may be an amount corresponding to the dimension of the depth B (FIG. 4) above and below the corrugated sheet 17 formed by pressing the steel plate, or the dimension of the carriage 47 provided with the electric magnet 65. Therefore, the vertical dimension of the press operation area set so as to be able to ascend is small, and the retreat of the upper die 33 above may be small. For this reason, the required hydraulic capacity of the press machine 23 is small, and the size of the press machine 23 can be reduced.

In the above steps, the electric magnet 65
When the sheet is adsorbed and carried out, the roller group 68 of a part of the carry-in conveyer 67 is moved up by the elevating device 69 to suppress the lower surface of the rear end of the steel sheet still on the carry-in conveyer 67.

If the weight of the steel sheet is large, the steel sheet is inclined by its own weight, so that the attractive force of the electric magnet 65 does not work well due to the inclination, and the rear end of the steel sheet comes into contact with the carry-in conveyor at a steep angle due to the inclination. And the smooth conveyance of the steel sheet may become difficult. However, since the steel plate is supported by the roller group 68 that has moved up, smooth conveyance is maintained.

(Other Embodiments) (1) In the above embodiments, it is the gas spring that supports the split upper die 33A for exerting the pad function in a protruding state. Not only the spring but also other means that can expand and contract to transmit the force from the upper die holder 31 to the split upper die 33A can be adopted.

(2) In the above embodiment, the steel plate is initially set on the lower mold 29 by moving on the carry-in conveyor 67. In other embodiments, the steel plate is set. It is also possible to perform this setting by suction using the electric magnet 65 of the carriage 47.

That is, in this case, the frame-shaped frame 45 is also protruded toward the near side in the transport direction (the left side in FIG. 7).
The bogie 47 can be moved not only to the right outside in the drawing of the press operation area but also to the left outside. Then, the carriage 47 that has moved to the left outside attracts and receives the steel plate by the electric magnet 65 when the frame 45 descends. Next, frame 45
Rises, and the carriage 47 moves on the frame 45 in the transport direction, thereby carrying in the steel plate.

Then, the electric magnet 65 of the carriage 47 on the frame 45 lowered in the press operation area.
Releases the adsorption of the steel sheet, and sets the steel sheet on the lower mold 29. After the setting, the frame 45 moves up, and the carriage 47 moves to the right outside of the press operation area.

Then, the upper die 33 descends to perform a pressing operation. Thereafter, the carriage 47 returns into the press operation area, the frame 45 descends again, the electric magnet 65 of the carriage 47 performs suction, the frame 45 rises, and the carriage 4
7 moves in the transport direction to carry out the steel plate. Further, the frame 45 descends with respect to the carry-out conveyor 71, the electric magnet 65 of the carriage 47 releases the suction, and the steel sheet is delivered. In this way, the first steel plate can be set in the lower mold 29 by the attraction of the electric magnet 65 of the carriage 47.

(3) In the above embodiment,
Only the roller group 68 (FIG. 8) that constitutes a part of the roller conveyor that is the carry-in conveyor 67 is a lifting device 69 (FIG. 7).
Although the lifting operation is performed according to (A)), in other embodiments, the entire roller conveyor may be moved up.

(4) In the above embodiment, the carry-out conveyor 71 is a belt conveyor, but in other embodiments, the carry-out conveyor 71 can be a roller conveyor like the carry-in conveyor 67. It is.
In this case, it is possible to raise the roller group which constitutes the whole or a part of the center of the roller conveyor which is the carry-out conveyor.

(5) In the above embodiment, the number of the electric magnets 65 provided on the carriage 47 is four. However, in other embodiments, the number of the electric magnets may be any number.

(6) In the above embodiment, the pressing operation is performed by lowering the upper die 33, but in other embodiments, the pressing operation is performed by lowering and lowering the lower die 29. It does not matter.

[0053]

As described above, according to the first, second, third or fourth aspect of the present invention, the pad pressure for pressing is set to 10% to 20% of the press bending force. In addition, the pad function can be exhibited without wasting the power of the press machine, and the return of the material can be prevented.

According to the third aspect of the present invention, the amount of elevation of the frame constituting the transfer device may be an amount corresponding to the vertical dimension of the waveform formed by pressing the steel plate, or the vertical dimension of the bogie provided with the electric magnet. . Therefore, the vertical dimension of the press operation area set so as to be able to ascend can be small, and the upward retreat of the upper die may be small.
For this reason, the required hydraulic capacity of the press machine is small,
The size of the press can be reduced.

In the fourth invention, furthermore, a roller group constituting the whole or a part of the center of the roller conveyor, which is a carry-in conveyor or a carry-out conveyor, is raised by an elevating device, so that the rear end of the conveyed steel plate is moved. The lower surface is supported, and it is possible to prevent the steel plate from being tilted, so that smooth conveyance is possible.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a state where a lower die and an upper die of a press used in one embodiment of the present invention are fitted.

FIG. 2 is an overall view showing a side wall of a bridge using a large corrugated steel sheet bent into a large corrugation by the mold of FIG. 1;

FIG. 3 is a perspective view showing a shape of the large-sized corrugated steel sheet of FIG. 2 at the time of shipment.

4 (A) is a side view, and FIG. 4 (B) is a plan view, showing the dimensions of the large corrugated steel sheet of FIG. 3 in a bent state.

5 is an overall front view of a press equipped with the mold of FIG. 1;

FIG. 6 is a front view of a transfer device included in the press of FIG. 5;

FIGS. 7A and 7B are side views showing the transport device of FIG. 6, in which FIG. 7A is a view of a front half in a transport direction, and FIG. 7B is a view of a rear half in a transport direction.

FIG. 8 is a plan view of FIG.

FIG. 9 is a plan view of FIG. 7 (B).

FIG. 10 is a cross-sectional view taken along the line XX of FIG. 1;

[Explanation of symbols]

 27 Lower Die Holder 29 Lower Die 31 Upper Die Holder 33 Upper Die 45 Frame 47 Dolly 49 Vertical Moving Means (Synchro Cylinder) 55 Wheel 57 Chain 59 Chain Sprocket 61 Drive Chain Sprocket 63, 81 Helical Bevel Gear Motor 65 Electric Magnet 67 Carry-in Conveyor 71 Unloading conveyor

Claims (4)

[Claims] A steel sheet is bent to form a large corrugated steel sheet having a plurality of large corrugations, and the steel sheet has a thickness of 8 to 16 mm.
In the above-mentioned molding method, the pitch of the waveform is 900 to 1800 mm, the depth of the waveform is 150 to 300 mm, and the dimensions of the top, bottom, and inclined portions of the waveform are about 250 to 500 mm, respectively. Using a press machine having an upper mold and a lower mold having two pitches, a step of conveying the steel sheet by one pitch to this press machine, and a waveform in which the upper mold and the lower mold for one pitch on the back side in the conveying direction are already processed. A pad step of pressing in advance, and a step of newly performing press bending of the upper die and lower die for one pitch on the front side in the transport direction in a state where the pressing is performed, and the pad pressure for pressing is A method for forming a large corrugated steel sheet, wherein the pressing force is 10% to 20%. 2. A steel sheet is bent to form a large corrugated steel sheet having a plurality of large corrugations, and the steel sheet has a thickness of 8 to 16 mm.
The pitch of the waveform is 900 to 1800 mm, the depth of the waveform is 150 to 300 mm, and the dimensions of the top, bottom, and inclined portions of the waveform are about 250 to 500 mm, respectively. A press having an upper die and a lower die having two pitches, a transport device for transporting the steel plate by one pitch to the press machine, and a pad for previously holding the waveform already processed by the upper die for one pitch on the back side in the transport direction. And a plurality of gas springs for supporting and projecting the upper mold for one pitch so as to have a function, so that the pad pressure for holding down is 10% to 20% of the press bending force. A large corrugated steel sheet forming apparatus characterized in that the number of gas springs and / or gas pressure are adjusted. 3. The apparatus according to claim 1, wherein the transfer device includes a frame-shaped frame that surrounds a lower die and an upper die of a press machine for pressing a steel plate in a horizontal plane;
A trolley that can reciprocate on the frame in the transport direction and can freely move into and out of the press operation area of the lower die and the upper die, an electric magnet provided on the trolley to attract the steel plate, and a loading side of the frame. The apparatus for forming a large corrugated steel sheet according to claim 2, further comprising: a carry-in conveyor connected thereto; and a carry-out conveyor connected to a carry-out side of the frame. 4. The large corrugated steel sheet according to claim 3, wherein the carry-in conveyor or the carry-out conveyor is a roller conveyor, and has a lifting device that moves up and down a roller group that constitutes all or a part of the roller conveyor. Molding equipment.