JPH0364214B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a container body by spirally winding and forming a strip material.

BACKGROUND ART Conventionally, a method has been developed in which a container body is manufactured by spirally wrapping a strip material around an inner cylinder while applying pressure using forming rolls, and at the same time welding the wrapped strip material. According to this manufacturing method, since the container body can be continuously formed in the axial direction, long-bodied containers can be easily manufactured, which is advantageous in terms of automation and labor saving, and the manufactured containers are Since the weld line has a certain angle to the axis and is evenly distributed around the entire circumference and has no directionality with respect to the axis, it is advantageous in terms of internal pressure strength, and can be used as a high-pressure vessel by stacking the strip material in multiple layers. is possible.

Fig. 1a is a perspective view of a container body manufactured by this manufacturing method by stacking multiple layers of strip material, and Fig. 1b is a partial vertical cross-sectional view thereof. In the manufacturing method, the strip material 2 is spirally wound around the outer peripheral surface of the inner cylinder 1, and from the viewpoint of strength, the opposing portions of the adjacent strip materials 2 and the circumferential portion formed on the inside thereof are welded 3. It's twisted and stuck. Because of this welding 3, when wrapping the strip material 2, there is an appropriate gap g ( For example, it is necessary to provide a length of about 4 mm) and wind it. However, this gap g fluctuates due to poor precision in the properties of the inner cylinder 1 (cylindricity, rigid cylinder), the properties of the strip material 2 (thickness, meandering, etc.), and it is necessary to maintain this within an appropriate range. Conventionally, there was a problem in that welding work and quality control required a great deal of effort.

As a method to adjust this gap g variation,
For example, the following methods may be considered.

(1) Method of winding the strip material 2 by moving it in the width direction of the strip As shown in FIG. When it has spread, the strip material 2 is relatively moved in the direction of the arrow to move to the position shown by the chain line. However, if the strip material 2 is simply transferred, the strip material 2 will undergo wave-like out-of-plane deformation, resulting in a clearance c, as shown in FIG. Therefore, it is not possible to weld between A1 and A2 in this state. Therefore, as shown in Fig. 4, it may be possible to weld while holding the strip material 2 along A3-B3-C3-D3 with a plate press roll, but if out-of-plane deformation is suppressed, most of the strip material 2 will be transferred between A1 and A3. The condition returns to the state before adjustment, and after all, the gap g cannot be effectively controlled. In addition, in FIGS. 3 and 4, the chain line represents the state before the transition adjustment of the strip plate 2 is performed.

(2) Method using heating control In this method, the strip material 2 is heated to cause thermal deformation, and this is used to adjust the gap g and weld quickly. As this heating method, as shown by diagonal lines in FIG. Displace it to the position shown. Conceivable heating methods include changing the heating area and changing the heating temperature, but there is a problem in that localized heating causes buckling and creates a clearance at the welding position. On the other hand, if the parts are cooled after being tack-welded at a high temperature, there is a problem in that the tack-joint parts will break due to thermal stress.

(3) Other methods It is also possible to adjust the gap g by bending the strip material 2 in the width direction by rolling or tensioning, but this has the problem of making the entire device large-scale and is not practical.

The present invention has been made in view of the above-mentioned problems, and it is possible to effectively control the size of the welding gap between adjacent strip materials, thereby improving workability and quality and reducing manufacturing costs. The object of the present invention is to provide a method for manufacturing a container body in a spiral manner.

The structure of the method for manufacturing a container body using a spiral method according to the present invention to achieve this objective is as follows:
In a method of manufacturing a container body by forming a band material on the outer circumferential surface of an inner cylinder, forming a weldable gap between adjacent band material, and forming the band material in a spiral shape, when adjusting the gap: , heating the strip material; moving the strip material and the inner cylinder relative to each other in the width direction of the outer strip material in a direction to eliminate gap errors; and temporarily welding the side edges of the strip material. The present invention is characterized by comprising a step of further relatively moving the strip material and the inner cylinder, and a step of temporarily welding a side end of the strip material opposite to the side where the temporary welding was performed.

An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 6 to FIG. 10 represent process explanatory diagrams of the manufacturing method according to the present invention.

As shown in FIG. 6, in the method for manufacturing a container body according to the present invention, a strip material 2 is spirally wound around the outer peripheral surface of an inner cylinder 1 with a gap g that can be welded. Temporary welding 3a (represented by black circles in the figure) is sequentially applied to the strip material 2 which has been welded, and then main welding 3 is performed by a welding machine 4. This gear g is monitored by a suitable detection means, which detects, for example, a gap error Δg with respect to an appropriate gap g at a predetermined distance l, and when the gap error Δg exceeds a permissible range, adjustment is performed in the following manner.

First, as shown in FIG. 7, the strip material 2 is heated by a heating means 5 such as gas or electricity at a position immediately before being wrapped.

Next, as shown in FIG. 8, while rotating the inner tube 1 at a predetermined rotation speed N, the strip material 2 and the inner tube 1 are moved a predetermined amount in the width direction of the strip material 2 in a direction that eliminates the gap error Δg. (Δg±α) relative movement 6. Thereafter, the rotation of the cylinder 1 is stopped, and the front side end A of the strip material 2 in the relative movement direction is temporarily welded. This strip material 2
With the relative movement 6 of I will do it. In addition, the relative movement 6 of the strip material 2
The clearance c generated by the strip material 2 is then
It is absorbed by thermal contraction during cooling, and the strip material 2 becomes in close contact with the inner member.

After temporarily welding the side end portion A, as shown in FIG. 9, after further relative movement 8 of the inner cylinder 1 of the strip material 2,
Temporarily weld side ends A and opposite side ends B, C, and D. This is done in the order of B, C, and D, and the distance between B and C is made relatively short. The reason why the strip material 2 is further moved relative 8 is that when the strip material 2 is heated to a considerably high temperature (for example, about 200°C), the side edges B, C, and D are moved without relative movement 8.
If temporary welding is performed, large restraint stress will occur between temporary welding positions A, B, C, and D as the temporary welding cools, which may cause the temporary weld to break or cause local deformation. It is. Therefore, in order to reduce the restraining stress during cooling of the strip material 2, the relative movement 8 of the strip material 2 is performed in advance to cause out-of-plane deformation along the width direction of the strip between both ends. The out-of-plane deformation expands to absorb thermal contraction. Therefore, at the end of cooling, the strip material 2
is in close contact with the inner member, and the temporarily welded portion will not break or local deformation will occur.

After the temporary welding of the side edges B, C, and D of the strip material 2 is completed, as shown in FIG. 10, the temporary welding positions A,
The inner tube 1 is rotated while the strip material 2 on the unwrapped side from B is pressed over substantially the entire width by the pressure roll 9, and the wrapping of the strip material 2 is continued.

As described above in detail with reference to one embodiment, according to the present invention, heating of the strip material and movement in the width direction of the strip are rationally combined, so that the gap for welding between adjacent strip materials is reduced. The size can be effectively controlled, thereby improving workability, improving quality, and reducing manufacturing costs.

[Brief explanation of drawings]

Fig. 1a is a perspective view of a container body manufactured by the present manufacturing method by stacking multiple layers of strip material, Fig. 1b is a partial longitudinal sectional view thereof, Figs. 2, 3, 4, and 5. The figures are explanatory diagrams of how to adjust gap fluctuations,
FIG. 6, FIG. 7, FIG. 8, FIG. 9, and FIG. 10 are process explanatory diagrams of a manufacturing method according to an embodiment of the present invention. In the drawing, 1 is the inner cylinder, 2 is the strip material, 3 is the welding, 3
a is temporary welding, 4 is a welding machine, 5 is a heating means, 7, 9
is a pressure roll.

Claims (1)

[Claims] 1. While forming a band plate material on the outer peripheral surface of the inner cylinder and forming a gap that can be welded between the adjacent band plate materials,
In the method of manufacturing a container body by spirally winding and forming, when adjusting the gap, the step of heating the band material, and rolling the band material and the inner tube in a direction to eliminate gap error. A step of relatively moving the plate material in the width direction of the plate material, a step of temporarily welding the side edges of the strip material, a step of further relatively moving the said strip material and the inner cylinder, and a step of performing the temporary welding of the strip material. 1. A method for manufacturing a container body using a spiral method, the method comprising the step of temporarily welding a side end portion and an opposite side end portion.