JPH10314837A - Helical deformed tube, method for forming and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stabilize the surface condition and the shape by disposing a plurality of forming rolls around a tube stock, supporting each of the rolls rotatably with roll chocks and forming a deformed tube which is equipped with a tube wall with helical waviness centering the tube shaft having an inclined roll shaft to the surface intersecting with the tube shaft at right angles and a weld bead parallel to the tube shaft. SOLUTION: A plurality of forming rolls 20, 20... each with inclined rotary shaft are disposed around the tube stuck. In the case of manufacturing a deformed tube P having eight ruggedness circumferentially, eight forming rolls 20 are disposed circumferentially at equal distance. By making the forming rolls 20 press the tube stock, shape corresponding to the profile of the forming roll 20 is formed on the tube stock. A deformed tube P with a tube wall (t) having recessed part (d) in helical waviness in the direction of tube shaft is obtained. The deformed tube P is not subjected to twisting so no stress due to moment is remained. Weld bead (w) is in parallel to the tube shaft so weld bead (w) is disposed on the rear side and an excellent appearance working is available.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deformed pipe having a pipe wall provided with undulation spiraled in the pipe axis direction, and a method and apparatus for forming the same.

[0002]

2. Description of the Related Art A deformed tube having a tube wall with irregularities in the circumferential direction is partially used as a deformed tube provided with design and distinctiveness. The unevenness of the pipe wall also plays a role of adjusting the flow path resistance in piping applications and the like. In the production of a deformed pipe having irregularities on the pipe wall, a roll forming method is partially adopted because of good productivity. For example, when manufacturing a deformed pipe P (FIG. 1) having a pipe wall t in which eight concave portions d extending in a direction parallel to the pipe axis are provided in the circumferential direction by a roll forming method, as shown in FIG. Forming rolls r _{1 to} r with caliber attached
Forming roll r using a forming stand with ₄ arranged on all sides
And by feeding raw tube round tube or the like in the molding space R surrounded by ₁ ~r _4. At this time, since the forming recesses d extending in the tube axis direction of the profiled pipe P, it is set to a direction orthogonal to the rotation axis of each forming roll r ₁ ~r ₄ to the tube axis. By the way, in recent years when needs are diversified, the design and the discriminability of a deformed pipe having a concave portion d parallel to the pipe axis have been reduced. Also,
Even when used in a piping application, since the recess d extends in the flow direction of the fluid flowing inside the deformed pipe P, an expected flow path resistance may not be obtained despite the formation of the recess d. . For this reason, there is a demand for a deformed pipe in which a helical recess d centered on the pipe axis is formed in the pipe axis direction.

[0003]

In order to form a deformed pipe having a spiral pipe wall, it is formed by in-line molding or a pipe forming line incorporating a dedicated forming stand on the outlet side of a round pipe forming line. Off-line molding for forming a round pipe into a deformed pipe on a separate line is conceivable. In the in-line molding, at least two or more molding stands are arranged, and the base tube is relatively rotated around the tube axis on the upstream side and the downstream side,
The tube wall must be formed in a spiral shape. In off-line molding, a helical deformed pipe is manufactured by first forming a deformed pipe having a cross-sectional shape (FIG. 1) parallel to the pipe axis direction and then twisting the deformed pipe cut to a predetermined length in the pipe axis direction. . That is, in both in-line molding and off-line molding, a tube wall is formed in a spiral shape in the tube axis direction by directly applying a twist to a deformed tube having a cross-sectional shape parallel to the tube axis direction. In such a method, the number of steps increases more than necessary.
In addition, not only large-scale equipment is required for directly twisting the deformed pipe, but also in the case of using a surface-treated raw pipe, there is a possibility that surface damage due to torsion may occur. Furthermore, since the weld bead also has a spiral shape, it is inevitable that the weld bead comes to the front side when the deformed pipe is used as a decorative member, and the appearance is deteriorated.

[0004]

SUMMARY OF THE INVENTION The present invention has been devised in order to solve such a problem, and a large equipment change can be made by inclining a roll rotation axis with respect to a plane perpendicular to a pipe axis. It is an object of the present invention to obtain a deformed pipe having a pipe wall undulating in the pipe axis direction without accompanying. In order to achieve the object, the spiral shaped pipe of the present invention has a pipe wall provided with a spiral undulation centered on the pipe axis, and has a weld bead extending in a direction parallel to the pipe axis. Features. This spiral shaped pipe is manufactured by forming a raw pipe with a forming roll in which a roll shaft is inclined with respect to a plane perpendicular to the pipe axis. The forming device includes a plurality of forming rolls arranged around the raw tube, and a roll chock rotatably supporting each forming roll. The roll chock is provided with a collar that supports the roll shaft while being inclined with respect to a plane perpendicular to the tube axis.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A molding apparatus according to the present invention is used independently of a pipe production line or in a form incorporated in a pipe production line. When manufacturing a deformed tube having a complicated shape, a plurality of molding stands are arranged in series according to a target shape. When the forming stand is arranged in a plurality of stages, the amount of processing in each stage is reduced, so that the load on the roll is reduced, and the processing can be performed with good shape accuracy. For example, as shown in FIG. 3, the molding device independent of the pipe-making line has a pushing device 11 disposed on the entrance side of the molding stand 10 and a correction stand 12 disposed on the exit side. The pushing device 11 uses a chuck (not shown) provided on the hydraulic cylinder 13 to rotate the round pipe P _0.
(Primary tube) is gripped and the round tube P ₀ is pushed into the molding stand 10. While round tubes P ₀ in the molding station 10 is molded, the bearing 1 for rotatably supporting a round tube P ₀
4 is provided on the hydraulic cylinder 13. The deformed pipe P in which the pipe wall is formed in a undulating shape in the pipe axis direction is sent out from the forming stand 10 and then corrected in shape by the correction stand 12.

[0006] In an in-line type molding apparatus incorporated in a pipe forming line, for example, as shown in FIG. The blank S paid out from the payoff reel 16 is rounded by the tube forming machine 15 into a round tube P _0.
After that, it is sent to the molding stand 10. In this case, since the rotation of the round pipe P ₀ is molded under conditions which are not allowed, the shaped stand 10 is supported by bearings 14, a method of rotating is adopted molded stand 10 itself. The deformed pipe P whose pipe wall is formed in a spiral shape by the forming stand 10 is sent out through the straightening stand.

[0007] As shown in FIG.
The number of forming rolls 20, 20,... According to the cross-sectional shape of the target deformed pipe P is provided. Roll chocks 21 rotatably supporting each forming roll 20 are provided on a stand frame 22 at equal intervals in a circumferential direction, and are urged in the center direction by a screw down screw 23. As shown in FIG. 6, the roll chock 21 has a space 24 for accommodating the forming roll 20, and is provided with a collar 26 into which a roll shaft 25 of the forming roll 20 is fitted. The collar 26 is attached to the roll chock 21 at an inclination angle θ so that the forming roll 20 is inclined with respect to the tube axis direction of the round tube P ₀ being formed. Tilt angle θ
Is set at an appropriate angle in accordance with the pitch of the helix attached to the tube wall of the deformed tube P. However, too large inclination angle θ
When the forming roll 20 is mounted in the above, the rotation of the forming roll 20 and the running of the raw tube P ₀ or the deformed tube P cannot be performed.
The inclination angle θ is set to 5 degrees or less.

[0008] Forming rolls 20, 20 whose rotation axes are inclined.
... is a plurality disposed around the base pipe P ₀ as shown in Figure 5 (a). For example, when manufacturing a deformed pipe P having eight irregularities in the circumferential direction, eight forming rolls 2
Are arranged at equal intervals in the circumferential direction. Each forming roll 20 is pressed against the base tube P _{0 as} shown in FIG. 7A to form the base tube P ₀ into a shape corresponding to the profile of the forming roll 20. As a result, as shown in FIG. 7 (b), the concave portion d has a tube wall t spirally undulating in the tube axis direction.
Is produced.

[0009] The resulting variant pipe P without twisting the base pipe P _0, since the tube wall t of the base pipe P ₀ is obtained by plastic deformation, without damaging the base tube P _0, shape stability Excellent in nature. Incidentally, the profiled tube was molded twisting the base pipe P _0, remaining deformed pipe P by the moment due to torsion is a stress, likely to cause deformation of the profiled pipe P. Further, in the case of forming the raw tube P ₀ made of surface-treated steel sheet, plating layer or the like to generate a defective or causes a reduction in the adhesiveness. Weld bead w formed pipe making process, unlike the deformed tube shaped twisting the base pipe P _0, which extends parallel to the tube axis direction without being helically. For this reason, for example, when used as a decorative building material, by arranging the surface on which the weld bead w is located on the back side, it is possible to perform construction with high designability and distinctiveness.

When forming rolls 20 having different profiles are used, it is also possible to produce deformed tubes having various helical shapes. For example, in a molding stand incorporating a flat roll as the molding roll 20 (FIG. 8A),
Since a round pipe P ₀ is molded by a roll circumferential surface of the flat roll, flat surface f is formed on the resultant deformed pipe P (FIG. 8
b). The flat surface f also undulates spirally in the pipe axis direction, similarly to the deformed pipe P in FIG. Also, one molding stand 1
When a combination of 0 and different forming rolls 20 is used, a profiled tube with undulations of different spiral states in the circumferential direction is produced. The number of concave portions d, flat surfaces f, and the like in the circumferential direction of the deformed pipe P is appropriately determined according to needs.

[0011]

EXAMPLE A steel pipe S having an outer diameter of 54.0 mm and a wall thickness of 1.6 mm.
Using TKM13B as a round tube P ₀ (base tube), FIG.
As shown in FIG. 7, the deformed pipe P was manufactured using the forming stand 10 in which eight forming rolls 20, 20,. As the forming roll 20, a roll having an outer diameter of 150 mm, a width of 20 mm, and a tip radius of 2.5 mm was used, and was attached to the roll chock 21 at an inclination angle θ of 5 degrees. The round tube P ₀ is pushed into the molding stand 10 by the pushing device 10 and has a maximum outer diameter of 48.
It was formed into a 5 mm shaped pipe P. Next, in order to improve the shape accuracy of the deformed pipe P, it was sent to the correction stand 12 and the pipe wall t of the deformed pipe P was pressed. In the obtained deformed pipe P,
4.0 m depth corresponding to the profile of the forming roll 20
Eight concave portions d were formed in the circumferential direction. Recess d
Had a spiral shape with respect to the tube axis direction so as to make a round around the deformed tube P with a length of 0.55 m in the tube axis direction of the deformed tube P.
On the other hand, the weld bead w was parallel to the pipe axis direction of the deformed pipe P.

[0012]

As described above, according to the present invention, a spiral pipe is formed on a pipe wall by forming a raw pipe with a forming roll whose rotation axis is inclined with respect to the pipe axis direction. Manufactures deformed tubes. This deformed tube is excellent in surface condition and shape stability, unlike a tube formed by twisting a raw tube. In addition, since the weld bead is parallel to the pipe axis direction, when used as a decorative building material or the like, a good-looking construction in which the weld bead is disposed on the back side can be performed.

[Brief description of the drawings]

Fig. 1 Conventional deformed pipe

FIG. 2 is a schematic view of a conventional roll arrangement for manufacturing a deformed pipe.

FIG. 3 A deformed pipe forming device provided independently of a pipe forming line

Fig. 4 Deformed pipe forming device incorporated in pipe making line

FIG. 5 is a view (b) of a forming stand incorporating a forming roll as viewed from the tube axis direction (a) and from the side.

FIG. 6 is a cross-sectional view (a) and a side view (b) of a roll chock to which a forming roll is mounted.

FIGS. 7A and 7B are schematic diagrams showing the relationship between a forming roll for forming a spiral recess and a round tube or a deformed tube, and the obtained deformed tube (b).

FIG. 8 is a schematic view showing the relationship between a forming roll for forming a spirally undulating flat surface and a round pipe or a deformed pipe (a), and the obtained deformed pipe (b).

[Explanation of symbols]

10: Forming stand 11: Push-in device 12: Straightening stand 13: Hydraulic cylinder 14: Bearing 15: Tube forming machine 16: Payoff reel 20: Forming roll 21: Roll chock 22:
Stand frame 23: Screw down 24: Roll storage space 2
5: Roll shaft 26: Color P: Deformed tube P ₀ : Round tube (base tube) S: Base plate
t: pipe wall d: concave portion f: flat surface w: weld bead θ: inclination angle of forming roll

Claims (3)

[Claims] 1. A spiral shaped pipe having a pipe wall provided with a spiral undulation centered on the pipe axis and having a weld bead extending in a direction parallel to the pipe axis. 2. A spiral characterized in that a base tube is formed by a forming roll in which a roll shaft is inclined with respect to a plane perpendicular to the tube axis, and a spiral undulation centered on the tube axis is attached to the tube wall. Method for forming irregular shaped pipes. 3. A roll shaft, comprising a plurality of forming rolls arranged around a raw pipe and a roll chock rotatably supporting each forming roll, and supporting the roll shaft by inclining with respect to a plane perpendicular to the pipe axis. A device for forming a spiral shaped pipe in which a collar is provided on a roll chock.