JPS6323855B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cylindrical ring forming apparatus.

When constructing a cylindrical storage tank such as a silo, in order to efficiently manufacture the cylindrical ring that makes up the circumferential body at low cost, the hot coil is unwound using a bending machine on-site, so that only one vertical weld seam is included. A method has been developed to fabricate a cylindrical ring that does not require As an apparatus for forming this cylindrical ring, there is one shown in FIGS. 1 and 2. This is composed of a payoff reel 2 on which a steel strip coil 1 is placed, a three-roll vertical bending machine 3, and a rotation guide ring 5 with a T-shaped cross section around which a steel strip 4 that has been formed into a curved shape is wound. is,
The guide ring 5 is placed on a horizontal roll 6, and its center of rotation is determined by vertical rolls 7 provided in the circumferential direction. Then, the steel strip is fed out from the payoff reel 2, curved to a predetermined curvature by a bending machine 3, and the curved steel strip 4 is wound around a guide ring 5 rotated by a feed roll 8. When the curved steel strip 4 is wrapped once around the guide ring 5 and a predetermined ring circumference is obtained, the unrolling and forming operation is stopped and the strip is cut at the A position. The cut curved steel strip 4 is lifted upward by a lifting device and removed from the forming device. Then, by butt welding the unrolled end and the cut end of the steel strip, a cylindrical ring containing only one longitudinal weld seam is produced.

According to this method, the cylindrical ring obtained from one coil is always formed in a steady state, except that the tip of the coil in the first ring of coil unwinding moves unsteadily between the bending machine 3 and the cutting position A. , it is possible to continuously mold cylindrical rings with stable curvature distribution. However, when forming the first ring of unwinding, the trajectory of the steel strip changes from the time the tip of the coil reaches the rotating guide ring until steady forming, resulting in a change in the curvature distribution of the ring. .

An object of the present invention is to provide a cylindrical ring forming apparatus that can manufacture a cylindrical ring having a uniform curvature distribution.

The curvature distribution of this first ring should be influenced by the positional relationship between the bending machine and the rotary guide ring and the position of the vertical roll. Therefore, the inventors conducted an experimental investigation on the stability of the curvature distribution of the first unwinding ring by changing the rotary guide ring position and the vertical roll position. The equipment used for the experiment is 1/8
It is a scale model, coil material: SPCC, coil dimensions: T = 0.6 ~ 1.6 mm, W = 200 mm (inner diameter 96 mm,
outside diameter 180mm), molded ring diameter: 500-1600mm.
FIG. 3 shows a coordinate system for displaying the positions of the rotation guide ring 5 and the vertical roll 7. The center of the bending and shaping machine 3 is used as a reference point for the X and Y coordinates, and the position of the vertical roll 7 is indicated by the deviation angle α from the center of the guide ring 5 and the distance δ between the outer diameter of the guide ring 5. The radius R of the rotary guide ring 5 was 300 mm, and the bending machine was set so that the radius of curvature of the ring obtained at the exit side of the bending machine 3 was 250 mm. Also, the first vertical roll 7
The positions of are α=15° and δ=25mm.

The results of the experiment are shown in Figure 4. a is X=650mm,
Y=0, b is X=550mm, Y=0, c is X=550
mm, Y=200mm. The radius of curvature ρ is obtained by dividing the cylindrical ring into five parts in the circumferential direction, numbering them 1, 2, 3, etc. from the tip end of the coil, and measuring the radius of curvature ρ of each divided piece.
Note that the white circle indicates the first ring, and the black circle indicates the second ring.

In both the first ring and the second ring, the curvature distribution is stable in case b when the rotation guide ring 5 is located as close as possible to the bending machine 3. From this, the curvature distribution can be stabilized by locating the center of the rotary guide ring 5 on the Y=0 line as close to the bending machine 3 as possible.

FIG. 5 shows an investigation of the effect on the ring curvature by fixing the position of the rotation guide ring 5 and changing the position of the first vertical roll 7. The triangle mark is α=
0°, δ=20mm, and the circle mark is for α=15°, δ=25mm. Note that the white part indicates the first ring, and the black part indicates the second ring. Compared to the case of α=0°, α
The curvature is stable at =15°.

This invention has been made based on the above findings. Depending on the actual machine, using a coil with coil material: SS41, coil dimensions: t = 6 to 12.7 mm, W = 1800 mm, the position of the first vertical roll is set to α = 15°, δ = 0.2 m.
We conducted a molding experiment on a cylindrical ring with a diameter of 9600 mm and obtained the following optimal conditions.

X=1.2R+1.5(m), Y=0 However, R = radius of rotation guide ring (m) The curvature distribution in this case was within ±10%.

The forming apparatus of the present invention has a rotary guide ring disposed close to the vertical bending machine on the X axis passing through the center of the vertical bending machine, and a vertical roll near the exit side of the vertical bending machine. is disposed at a position 105° from the X-axis with the center of rotation of the rotation guide ring as the center, thereby making it possible to manufacture a cylindrical ring with a stable curvature distribution.

[Brief explanation of the drawing]

Figures 1 and 2 show a conventional cylindrical ring forming device. Figure 1 is a plan view, Figure 2 is an enlarged perspective view of the part shown in Figure 1, and Figure 3 shows a rotary guide ring and a vertical ring. Explanatory diagram of the roll coordinate system, Figure 4 a, b, c
5 is an explanatory diagram showing the relationship between the rotation guide ring position and the curvature radius distribution, and FIG. 5 is an explanatory diagram showing the relationship between the vertical roll position and the curvature radius distribution, respectively. 1...Steel strip coil, 2...Payoff reel, 3
... Vertical bending machine, 5 ... Rotating guide ring, 7
... Vertical roll.

Claims (1)

[Claims] 1. A payoff reel that unwinds a steel strip wound into a coil, a vertical bending machine that shapes the unwound steel strip into a curved steel strip with a predetermined curvature, and a rotation that winds the curved steel strip. In a device consisting of a guide ring and a plurality of vertical rolls provided in the circumferential direction that determines the rotation center of the rotation guide ring, the rotation guide ring is vertically bent on an X axis passing through the center of a vertical bending machine. The vertical roll near the exit side of the vertical bending machine is placed close to the forming machine, and the vertical roll is moved from the X axis around the center of rotation of the rotary guide ring.
A cylindrical ring forming device characterized by being arranged at a 105° position.