JPH0329490B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a method of manufacturing a hollow conical section of a steel manufacturing welded structure such as a hopper.

Conventional technology Normally, when manufacturing welded steel structures such as silos, the size of the steel plates brought in from the mill is limited, and due to transportation problems, etc., it is necessary to assemble them at the site where they are installed. Welding, inspection, etc. are being carried out. Therefore, cone-shaped structures such as hoppers were assembled using a method of assembling steel plate members that had been pressed in a factory, even if temporary supports and frames were assembled on-site. Processing costs and on-site man-hours are required,
It also caused inconvenience in terms of welding, inspection, etc.

Further, Patent Publication No. 45752/1983 describes a method for manufacturing hollow conical structures such as hoppers and silo roofs on site. This method discloses a method in which a rope is wound around the circumference of an expanded flat plate with a conical portion expanded, and this rope is squeezed using a crane or the like, thereby making use of the bending deformation of the material due to its own weight. . However, with the construction method based on this method, it is difficult to form a conical shape efficiently and with high precision. The reason for this is that when the conical inclination angle is large, that is, when the unfolded angle is close to 180 degrees, it is difficult to cause the initial deformation of the material to occur smoothly just by squeezing the rope and the material's own weight as described above. This causes local deformation, making it difficult to deform evenly. Further, if such non-uniform deformation occurs, manufacturing efficiency will be reduced and the precision of the product itself will be reduced.

Problems to be Solved by the Invention The purpose of the present invention is to solve the above-mentioned problems with the prior art, to produce a hollow conical structure made of steel plate, which has good finished dimensional accuracy, and which has good production efficiency by significantly reducing the number of man-hours on site. We aim to provide the following.

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

FIG. 1 is a schematic front view of the silo, with reference numeral 1
A method of manufacturing a hopper, which is a hollow conical structure indicated by 00, having an inclination angle α of 60° will be described as a first embodiment. First, second
As shown in Figure A, the steel plate 1 is laid out in the shape of an expanded cone so that the inclination angle α when assembled as shown in Figure 1 is 60°. Reference numeral 30 indicates a weld line between the steel plates, and the integral expansion plate 10 is formed by welding. This welding can usually be performed by butt welding, and therefore, the steel plate is welded from two sides, the front and back sides. in this case,
It may be convenient to follow the following steps: After the welding on the front side is completed, the reversing piece 2a for reversing is attached to the expansion plate 10 by temporary welding,
Then, a reversing jig 3 (for example, H-beam steel) with a roller 4 as shown in FIG. As shown in the figure, the expansion plate 10 is lifted in the direction of the arrow using a balance 31 by a crane (not shown) and turned over as shown in FIG. 3 so that the welded side becomes the back side. After the reversal is completed, the fasteners that fasten the piece 2a and the reversing jig 3 are removed to separate the unfolding plate 10 and the reversing jig 3, and then one of the unfolding plates 10 is removed as shown in FIG. Lift the end with a crane or the like in the direction of the arrow and use the rope attached to the reversing jig to pull out the reversing jig 3, lift the other end in the same way, pull out the reversing jig 3, and deploy it. Welding is performed on the side of the plate 10 opposite to the side on which the welding was performed. By the above method, butt welding between the front and back surfaces of the expansion plate can be easily and efficiently carried out.

In addition, the reversing piece is made by gas cutting a steel plate to form a flat flat plate 10, as shown by reference numeral 2b in FIG. 2A.
When forming the circumference, the reversing piece 2b may be left and cut so as to be integrated with the expanding plate, and such reversing piece 2b may be cut and removed after the aforementioned expanding plate is reversed. .

FIG. 4 is a plan view of the developing plate 10 in which the necessary members are arranged to properly form the developing plate 10 into a conical shape by a narrowing process to be described later. The wire 5 is wound around a pulley 6 arranged approximately symmetrically with respect to the center line CL of the expansion plate 10 at an interval of about 1500 mm on the periphery of the expansion plate, and one end of the wire 5 is formed into a conical shape by the expansion plate 10. A portion where the wire 5 is wound across the center line CL via a pulley 6 disposed near the joint weld joint 9 of the expansion plate that forms a joint weld line in the cone meridian direction when is fixed by a wire fixing piece 7 attached by welding near the joining joint 9 of the expansion plate 10 on the opposite side to the center line CL, and the other end of the wire 5 is pulled up by a crane. The expansion plate 0 can be narrowed down by the following. Further, it is desirable that the wire fixing piece 7 is placed at about one-third of the deployment radius of the deployment plate in the direction from the center line CL to the peripheral edge of the deployment plate. Furthermore, on the surface of the expansion plate around which the wire 5 is wound, a restraining piece 8 for restraining the expansion plate is attached near the joining joint 9, and this restraining piece 8 is used to As shown in FIG. 5, the joining joint 9 side of the expanding plate 10 is restrained so that the initial conical deformation of the expanding plate occurs smoothly. Further, on the surface of the expansion plate on the side around which the wire 5 is wound, and in the vicinity of the joining joint 9, there is a space where the joining joints 9 in the opposite cone meridian direction do not overlap when the wire 5 is narrowed down. Stoppers 22a and 22b are arranged to allow smooth skin matching. In addition, in order to cause the initial deformation of the expansion plate 10 to occur smoothly and to form a conical shape with high precision, the surface of the expansion plate 10 on which the wire 5 of the expansion plate 10 is not wound is restrained during initial narrowing. A restraint piece 12 is attached for the purpose of doing so. This restraint piece 12 is a wire 5
It is preferable that they be placed on the surface of the unfolding plate on the unwound side and at approximately equal intervals in the circumferential direction on a circumference with a radius of approximately 1500 mm from the center O of the circumference of the unfolding plate. . In this embodiment, three restraint pieces are evenly spaced. Furthermore, the development plate 1
0, a main hook piece 13 is attached to the surface of the expansion plate on the side around which the wire 5 is wound. This main hook piece 13 is placed on a circumference of about two-thirds of the circumferential radius of the deployment plate from the center O of the deployment circumference of the deployment plate 10 and approximately symmetrical to the center line CL. It is preferable to install it approximately 400mm away from the center line CL. As shown in FIG. 5, the main hook piece 13 supports the expanding plate in a well-balanced manner when squeezing the wire 5 wound around the expanding plate 10 to prevent local deformation so that the expanding plate is evenly conical. It is used to transform into.

Next, a procedure for forming the expansion plate 10 into a conical shape will be explained. FIG. 5 shows that in order to cause initial deformation in the unfolding plate 10, a crane or the like (not shown) is used to pull up the free end of the wire 5 in the direction of the arrow to apply squeezing deformation to the unfolding plate 10. Then, a wire is attached to the parent hook piece 13 attached to the unfolding plate 10 so that the entire unfolding plate deforms in a well-balanced and uniform manner, and is pulled up in the direction of the arrow by a crane or the like (not shown), thereby causing the initial conical deformation of the unfolding plate. This shows the state in which a At this time, the unfolding plate 10 is restrained using the restraining pieces 8 and 12 as shown in FIG. That is, the wire attached to the restraining piece 12 attached to the side forming the conical outer surface of the expanding plate 10 is applied with a tensile force in the direction of the arrow by a crane or the like (not shown) to restrain the expanding plate. The entire expansion plate is compressed uniformly to prevent local deformation. As shown in FIG. 6, this restraint is such that the expansion plate 10 undergoes initial deformation and the expansion angle θ of the expansion plate becomes approximately the same as the expansion angle θ of the hopper expansion plate having an inclination angle α of 45°. Release when deformed. Also, at this time, the restraint in the vicinity of the conical meridian joint 9 of the expansion plate is also released. At this time, the developing plate is deformed into a shape as shown in FIG. In this example, the development angle θ of the deformed development plate is the development angle θ of the hopper development plate having an inclination angle α of 45°.
However, the degree of initial deformation of the expansion plate when releasing the restraint is not limited to this, and in other words, the degree of initial deformation of the expansion plate when the restraint is released is not limited to this. The initial deformation state may be such that the developing plate can be formed into a conical shape in a precise and uniform manner based on the following. The developing plate with such initial deformation is formed into a cone according to the following procedure.

The wire attached to the main hook piece 13 attached to the unfolding plate 10 is pulled up by a crane (not shown), and at the same time, the wire 5 wound around the unfolding plate is pulled up by a crane (not shown). By pulling it up, the expansion plate is narrowed down and the weight of the material itself causes the seventh
Cone forming is performed while adjusting the respective pulling forces in the order of Fig. A, Fig. 7B, and Fig. 7C.
As shown in Fig. 8A, the joining joints 9 in the cone meridian direction of the expansion plate 10 are brought close to each other without overlapping each other by stoppers 22a and 22b attached to the expansion plate 10, and are aligned using a hitch parer or the like. . Furthermore, in order to perform proper welding, the misalignment of the joining joint 9 is adjusted using the handle 16 and the arrow 17 shown in FIG. 8B to obtain an appropriate groove. Next, the hollow conical structure is completed by welding the conical structure while maintaining the groove of the joining joint 9 in the cone meridian direction appropriately. After this welding is completed on the inner surface of the cone, the conical structure may be reversed using the restraining piece 12 as shown in FIG. 8C, and welding may be performed on the outer surface of the cone.

FIG. 9 shows another embodiment for forming a hollow conical hopper with an inclination angle α of 60°. Components that are the same as those in the embodiment of FIG. 4 are given the same reference numerals. In FIG. 9, the wire 5 is wound almost symmetrically with respect to the center line CL via a pulley 6 placed on the periphery of the expansion plate 10, as in FIG. One end of 5 is a pulley 1 arranged and fixed outside the expansion plate 10 on the side where the wire is wound across the center line CL and on the opposite side to the center line CL.
It is fixed to a wire fixing piece 7 attached to the expansion plate via a wire 8. It is desirable that the fixing piece 7 be installed near the joining joint 9 in the meridian direction of the cone, at a distance of about one-third of the radius from the center line CL in the direction of the peripheral edge of the expansion plate. In addition, the pulley 18 fixed outside the expansion plate is located at the center line.
At a distance from CL of about one-third of the deployment radius of the expansion plate in the direction orthogonal to the center line CL and from the joint 9 in the direction orthogonal thereto, the expansion plate 10 is pulled up and the joint 9 The pulley 18 is fixed to the surface plate at a position where it does not interfere with the expanding plate when they approach each other and the expanding plate deforms into a conical shape. In addition, in this embodiment, since the fixed pulley 18 restrains the vicinity of the joint 9 in the cone meridian direction, the restraining piece 8 is used as described above to move the expanding plate in the cone meridian direction as shown in FIG. joint 9
There is no need to restrict. However, in the case of this embodiment as well, similar to the above-mentioned embodiment, there is a surface of the developing plate on the side where the wire 5 is not wound in order to cause the initial deformation of the developing plate to occur uniformly and smoothly. A restraint piece 12 for restraint is attached. A piece 13 for the main hook is attached in the same manner, and by pulling up the wire attached to this piece 13 and the wire 5 while adjusting it with a crane, a highly accurate conical shape can be created.

The conical molding manufacturing procedure is similar to the above-described embodiment, in which the expanding plate is first restrained to cause initial deformation as shown in FIG. A hopper is formed by the above-described procedure while adjusting the pulling force with the wire attached to the piece 6.

Next, a method for forming a hollow conical structure having an inclination angle α of 45° will be described. In this embodiment as well, the same reference numerals are used for the same members as in the previous embodiment. Figure 10 shows wire 5
FIG. 2 is a plan view of the unfolding plate 10 in a state where it is rolled up.
In this example, since the expansion angle θ of the expansion plate 10 is larger than that of the above-mentioned example, the setup and process for causing the initial deformation as described above are necessary in order to efficiently and uniformly form the cone. do not have. Also in this embodiment, the wire 5 is connected to the expansion plate 10.
The wire is wound approximately symmetrically around the center line CL around the periphery of the expansion plate 10 via pulleys 6 arranged at intervals of about 1500 mm on the periphery of the wire, and one end of the wound wire is It is fixed to a fixing piece 7 attached near a joining joint 9 in the cone meridian direction on the opposite side to the side on which the wire is wound across the center line CL. The fixing piece 7 is preferably attached near the joint 9 at a distance of about one-third of the deployment radius in the circumferential direction from the center O of the deployment plate 10. The attachment direction of the fixing piece 7 is determined by the tensile force of the wire when the expanding plate is deformed into a conical shape, as in the above-described embodiment.
They are arranged in a balanced direction so that no local deformation occurs. The other end of the wire 5 is a free end so that it can be squeezed by a crane. In this embodiment as well, the main hook piece 13 is located approximately 2/3 of the radius of the unfolding plate from the center O of the unfolding plate and about 400 meters from the center line CL to the left and right so that it is approximately symmetrical with respect to the center line CL.
Mounted at a distance of mm. Deployment plate 1
Reversing pieces 21 are attached on the surface of the expansion plate on the side opposite to the side on which the wire 5 is wound at approximately equal intervals on a radius circumference of about 1500 mm from the center O of 0, and a conical joint is formed. After welding of the conical inner surface of the joint 9 is completed, the conical structure is reversed using the reversing piece 21, and welding of the conical outer surface is performed.

In this example, the inclination angle α of the conical structure is
Since the angle of inclination α is 45°, the expansion angle of the expansion plate is large, unlike the example described above, in which the inclination angle α is 60°, the restraining pieces 8 and 12 are not attached to allow the initial deformation of the entire expansion plate to occur smoothly. Not yet. Therefore, in drawing for cone forming, tension is applied to the expanding plate using the restraining piece 12 attached to the expanding plate surface on the opposite side to the side on which the wire is wound as described above. Also, there is no need to restrain the vicinity of the joining joint 9 in the cone meridian direction. Therefore,
The narrowing down procedure can be carried out immediately from the manufacturing procedure after the initial deformation of the expansion plate described above is completed. That is, the wire attached to the main hook piece 13 is lifted up by a crane (not shown), the wire 5 wound around the expansion plate is squeezed upward by the crane (not shown), and the pulling force of these wires is adjusted. Cone forming is performed in the state shown in FIGS. 7A to 7C by squeezing with a wire and the weight of the material itself. In this case as well, the stoppers 22a and 22b attached to the expansion plate cause the conical joints 9 to approach each other without overlapping each other, and the joints 9 are properly maintained. Welding is performed from the inner surface, and then a wire is hung on the reversing piece 21 and the conical structure is reversed using a crane or the like, and the outer surface of the cone is welded to complete conical formation. In this embodiment, the inclination angle α of the conical structure is preferably 50° or less, that is, 45°. Even if the conical inclination angle α is 50° or more, conical forming can be performed according to the present invention.

Based on the cone forming method described above, there is no need to press the steel plates for each constituent member one by one to form the conical structure, and the steel plates sent out from the mill can be used directly as they are, resulting in consistent production. Since hollow conical structures such as hoppers can be manufactured in the process, the number of manufacturing steps can be significantly reduced. Furthermore, according to the method according to the invention,
Since it can be done with a small number of people, for example,
Two welders are put together, the steel plate is cut,
If three people are involved in the work such as inversion and cone forming, hollow cone-shaped structures such as hoppers can be efficiently manufactured on the first surface plate and the second surface plate as shown in Fig. 11. This makes it possible to mass produce in a short period of time.

Figure 11 shows the flow of manufacturing a hollow conical structure at two locations, the first surface plate and the second surface plate. , 2 cutting and reversing the developing plate, 3 welding the back side of the developing plate, and 4 hopper cone forming. The one-dot chain line in the figure shows the work flow of a welder, and the broken line shows the work flow of a worker who performs operations such as cutting, reversing, and forming cones of a steel plate. According to this, after the welder completes welding on the front side of a developing plate on the first surface plate, the welder goes to the second surface plate in the order indicated by the dashed-dotted arrow and welds the front side of another developing plate. Perform welding. Thereafter, the welding contractor proceeds with the work according to the flow of arrows indicated by the dashed-dotted line. on the other hand,
The worker gas-cuts the periphery of the developing plate whose front side has been welded, turns the developing plate in the same manner as described in the example of this application, and then performs the first welding process as shown by the dashed arrow. Go to the second surface plate and perform the same operation on the other developing plate, and then proceed with the operation according to the flow shown by the broken line arrow. Based on this flow, hoppers can be mass-produced efficiently with a small number of people.

Although the method for manufacturing a hollow conical structure has been described above, the present invention is not limited to the embodiments described so far, but is based on the content shown in the claims.

[Brief explanation of drawings]

FIG. 1 is a schematic front view of the silo. 2nd A
The figure is a plan view of a developing plate that constitutes a conical structure that is developed on a plane. FIG. 2B is a diagram showing a state in which the unfolding plate is lifted up for reversing the unfolding plate. FIG. 3 is a diagram showing a cross section of the developing plate after being reversed, and a reversing jig is attached to the developing plate. FIG. 4 is a plan view of a developing plate with a conical inclination angle α of 60° with necessary jigs such as wires arranged for drawing forming. FIG. 5 is a sectional view showing a state in which the expanding plate is restrained in order to be lifted up by a crane and subjected to initial deformation. Figure 6 shows that the cone inclination angle α is
It is a plan view in a state where the initial deformation of the expansion plate of 60° has occurred, and θ indicates the initial deformation angle of the expansion plate. 7th A
7B and 7C are diagrams showing a state in which the expansion plate is deformed into a conical shape. FIG. 8A is a plan view showing the state of skin contact of the joining joint in the cone meridian direction of the expansion plate. FIG. 8B is a cross-sectional view of the joining joint in the conical meridian direction of the expansion plate, showing the state of adjustment of the joint. FIG. 8C is a diagram showing a state in which a conical structure in which a developing plate is formed into a conical shape is inverted and lifted up by a crane. FIG. 9 is a plan view of another embodiment of the developing plate in which the conical inclination angle α is 60°, with necessary jigs such as wires arranged for drawing forming. FIG. 10 is a plan view of a developing plate with a conical inclination angle α of 45° with necessary jigs such as wires arranged for drawing forming.
FIG. 11 is a process diagram for efficiently manufacturing a hopper. Explanation of the signs of the main parts, α... Cone inclination angle, θ
...Development angle of the development plate, 3...Reversing jig, 5...Wire, 6...Pulley, 7...Fixing piece, 8...
...Restraint piece, 9... Conical meridian joint, 10... Expansion plate, 12... Restraint piece, 1
3... Main hook piece, 18... Pulley, 21...
... Reversing piece, 22a, 22b... Stopper.

Claims (1)

[Scope of Claims] 1. A method for manufacturing a hollow conical structure having a predetermined cone inclination angle, comprising: manufacturing a flat flat plate for defining the hollow conical structure; A pulley is arranged on the circumferential edge of the expansion plate, and one end is fixed to the expansion flat plate, and the pulley is arranged on the periphery of the expansion flat plate.Using the pulley, the expansion is carried out almost symmetrically with respect to the axis of symmetry of the expansion flat plate. a step of winding two wires around the periphery of the flat plate, restraining the vicinity of the joining joint of the expanded flat plate which becomes the joining joint in the meridian direction of the conical structure, and further winding the wire of the expanded flat plate. a step of restraining the surface of the flat plate on the side opposite to that of the flat plate, and gradually lifting the flat plate using a parent hook bead placed on the surface of the flat plate on the side around which the wire is wound. applying a tensile force to the unfixed end of the wire to narrow the wire and causing the expansion plate to undergo a predetermined initial deformation; When initial deformation occurs, maintaining the initial deformation and releasing the restraint near the joining joint and the restraint of the deployable plate on the side opposite to the side on which the wire is wound of the deployable plate; , While urging the initially deformed deploying plate upward in the direction in which the deploying plate is pulled up using the parent hook bead, a pulling force is applied to the unfixed end of the wire. a step of squeezing the feeder wire to deform the expansion plate into a substantially hollow conical shape; and adjusting the opposing joining joints so that when the expansion plate is deformed into the substantially hollow conical shape, the opposing joining joints can be welded. A method for manufacturing a hollow conical structure, comprising the steps of maintaining the conical deformation of the expansion plate by restraining it, releasing the tensile force of the wire, and welding the joining joint. 2. The developed flat plate is a steel plate, and the step of manufacturing the developed flat plate includes the steps of welding the steel plates together on one side of the steel plates, and attaching a reversing jig to the steel plate on the side welded on one side. 2. The hollow shape according to claim 1, wherein the steel plate is lifted and reversed, and after the reversing jig is removed, welding is performed on the side opposite to the welded side. Conical structure manufacturing method. 3. The fixed position of the wire is such that the wire wound around the expanded flat plate crosses the axis of symmetry of the expanded flat plate and is located at the junction of the rolled side and the expanded flat plate on the opposite side with respect to the axis of symmetry. 2. The method of manufacturing a hollow conical structure according to claim 1, wherein the hollow conical structure is near a joint. 4. The expanding flat plate on the side forming the conical outer surface where the wire is not wound is restrained by a restraining bead placed on the expanding flat plate on a radius of approximately 1500 mm from the center of the circumference of the expanding flat plate. 2. The method of manufacturing a hollow conical structure according to claim 1. 5. A method for manufacturing a hollow conical structure having a predetermined cone inclination angle, comprising the steps of: manufacturing a flat flat plate for defining the hollow conical structure; and providing a pulley on the circumferential edge of the flat flat plate. The pulleys are placed on the periphery of the deployable flat plate, and one end is fixed to the deployable flat plate, and the pulley is disposed on the periphery of the deployable flat plate. winding the wire, and urging the deployable flat plate upward, which is the direction in which the deployable flat plate is pulled up, using a parent hook bead placed on the surface of the expandable flat plate on the side around which the wire is wound. and applying a pulling force to the unfixed end of the wire to squeeze the wire and deforming the expanded plate into a substantially hollow conical shape; and deforming the expanded plate into a substantially hollow conical shape. When this happens, the conical deformation of the expansion plate is maintained by adjusting and restraining the joints in the opposing conical meridian directions so that the joints in the conical meridian direction can be welded, and the tensile force of the wire is released, and the A method for manufacturing a hollow conical structure, comprising the steps of welding a joining joint. 6. The developed flat plate is a steel plate, and the step of manufacturing the developed flat plate includes the steps of welding the steel plates together on one side of the steel plates, and attaching a reversing jig to the steel plate on the side welded on one side. 6. The hollow shape according to claim 5, comprising lifting the steel plate and inverting it, removing the reversing jig, and then performing welding on the side opposite to the welded side. Conical structure manufacturing method. 7. The fixed position of the wire is such that the wire wound around the expanded flat plate crosses the axis of symmetry of the expanded flat plate and is located at the junction of the rolled side and the expanded flat plate on the opposite side with respect to the axis of symmetry. 6. The method for manufacturing a hollow conical structure according to claim 5, wherein the hollow conical structure is near a joint.