JPS6210728B2 - - Google Patents

Description

[Detailed Description of the Invention] A metal strip is bent by a cold roll forming method, and during the process of forming a pipe, the strip is gradually bent into a semi-cylindrical shape, and the metal strip is inserted between the free ends of the strip. Pipe forming is performed by passing through a series of fin pass rolls having a roll structure with protruding disk-shaped fin rolls that support the pipe. The present invention relates to this fin pass roll structure.

The fin pass roll has a structure consisting of a fin roll that fits between the free ends of a strip bent into a semi-cylindrical shape in the center and supports it, and side rolls that are placed on both sides of the fin and form the strip into a cylindrical shape. This has been done in the past, and the three methods shown in FIGS. 1 to 3 are common.

In the method shown in FIG. 1, the fin roll 1 and side rolls 2 and 3 rotate together by receiving the driving force of a shaft 4 to send the strip forward.

In this method, the semi-cylindrical free end is strongly pressed against the fin roll and side roll. The fin roll is fixed to the side rolls on both sides, and the semi-cylindrical strip plate, which is given rotational force by a shaft, moves forward due to the frictional force with the roll due to the rotational force of the roll. Since the circumferential speed of the belt plate differs depending on the size of the diameter, there is always a speed difference between the belt plate and the belt plate that moves forward at the same speed, resulting in slippage.

The parts where the roll and the strip are most strongly crimped are the parts 5 and 6 where the free ends of the strip come into contact, but if the strip slips while being strongly crimped, the parts 5 and 6 will be damaged due to large friction. causes significant roll wear. Due to the irregular progress of this wear and the irregularity of the free end surface of the strip, an impact force is applied to the roll, and the strip free end contact portions 5 and 6 of the roll easily chip off. Moreover, the free end of the strip may be distorted due to slipping, and the strip surface may also be damaged.

The structure shown in FIG. 2 was created to improve the above-mentioned drawbacks. In FIG. 2, the strip free end surface 7
In order to eliminate slippage between the fin roll 8 and the side roll 8, the fin roll 8 is rotated independently from the side rolls 9 and 10. Although this improvement eliminates the above-mentioned drawbacks of the free end surface 7, the side roll and fin roll still In the vicinity of the dividing portion 11, the slippage between the side rolls and the strip plate cannot be resolved, and all of the above requirements have not yet been satisfied.

FIG. 3 shows a structure in which the dividing position of the fin roll 12 is placed at the middle of the hole-shaped curved surfaces of the side rolls 13 and 14. Since the fin roll 12 and side rolls 13 and 14 are usually fixed with bolts or the like, slippage between the free end of the strip and the rolls cannot be eliminated, and roll wear is large, causing distortion of the free end of the strip and the surface of the strip. There was a drawback that damage occurred.

The present invention provides a fin pass roll that eliminates the drawbacks of the conventional structure described above. The features of the present invention are that the fin roll is divided into three parts including the hole-shaped curved surface and rotates independently through a sleeve, and the dividing surface of the fin roll and side roll, which rotate independently through the sleeve, has a hole-shaped curved surface. It is constructed so that the cross section is almost perpendicular to the other.

The present invention is shown in FIGS. 4 and 5 and will be explained in detail based on the drawings. In FIGS. 4 and 5, 15 indicates a semi-cylindrical strip, 16 indicates fins, 17 and 18 intermediate rolls, 20 and 21 side rolls, and 19 a sleeve. There is. S indicates a hole-shaped curved surface. side roll 20,2
1 and the sleeve 19 are normally fixed together by a bolt 22 and a nut 23, and rotate as one unit by receiving rotational force from the roll shaft. On the other hand, the fin roll 31 includes the fin 16 and the intermediate roll 17,
18, and is located on the outer periphery of the sleeve 19 via a needle bearing 24, and is located between the side rolls 20 and 21, and the dividing plane from the side rolls is a hole when viewed in cross section. The partial surface in the vicinity of contact with the mold curved surface S is formed to be approximately perpendicular to the tangential direction of the hole mold curved surface.

The fin roll 31, which is a set of the fin 16 and the intermediate rolls 17 and 18, is configured to be able to rotate independently and freely at different speeds. By doing this, the dividing surface between the fin roll 31 and the side roll is reinforced, and roll wear due to independent rotation of the fin roll and wear of the dividing surface due to the difference in rotation speed of the side rolls can be prevented, resulting in a long life of the fin pass. It becomes a roll. Also fin roll
31 is also divided into intermediate rolls 17, 18 and fins 16, and each rotates freely, so the strip plate 1
This has the effect of eliminating resistance due to sliding friction that occurs between the free end of 5 and the contacting portions 25, 26. That is, the most strongly crimped portion of the strip and roll is the portion 25 that contacts the free end of the strip;
26, but this part is a fin roll (1 for division)
The side roll 20,
This means that it is out of 21. The side rolls and the lower roll 27 rotate by receiving rotational force from the roll shafts 28 and 29, thereby sequentially advancing the strip by frictional force with the strip, and at the same time serve to form the strip into a cylindrical shape. At this time, side roll 20,2
1 and the lower roll 27 have a large difference in diameter between the parts that contact the strip, so even if the rotation speed is the same, there will be a difference in circumferential speed due to the difference in diameter. However, since the free end of the strip, where the strip and roll are most strongly crimped, does not come into contact with these rolls, this can lead to large roll wear, roll chipping, and strip surface No defects such as damage will occur.

On the other hand, the fins 16 and the intermediate rolls 17, 18, which are most strongly pressed against the strip, have a small difference in diameter, and are able to rotate independently at the same speed as the free end surface of the strip, which advances at a constant speed. Since this is possible, only the forming force required for forming the strip into a cylindrical shape can be applied to the strip with almost no slippage at the contact portions between the free end of the strip and the fins and the intermediate roll. Therefore, the wear of the fins 16 and the intermediate rolls 17, 18 is significantly reduced, and all of the above-mentioned conventional drawbacks such as chipping of the fin rolls and damage to the surface of the strip are eliminated.

In addition, although this is the part 26 where conventionally slipping due to the difference in circumferential speed caused wear and chipping of the roll, intermediate rolls 17 and 18 as fin rolls
By independently rotating the rollers, the wear and frictional heat caused by sliding can be significantly reduced, but by using materials with high wear resistance and heat resistance for the intermediate rolls 17 and 18, the life of the rolls can be extended. can do.

Also, side rolls 20, 21, intermediate roll 17,
By dividing the roll into the fins 18 and fins 16, only the unusable part of the roll can be replaced and used.

5 differs from the structure in FIG. 4 in that the fins as the fin roll 31 and the intermediate roll are located on the outer periphery of the sleeve 19 via the needle bearing 24, whereas in this embodiment the fin 16
The only difference is that a film roll 31 consisting of a pair of intermediate rolls 17 and 18 is directly fitted into the outer periphery of the sleeve 19, and the sleeve acts as a sliding bearing, and the other structures are the same. Although needle bearings are used as bearings in the embodiments of the present invention, the present invention is not necessarily limited to this, and any bearing that can receive a radial load may be used. Therefore, the effect produced by this embodiment is the same as the fourth one mentioned above.
Everything is the same as the embodiment shown.

As explained above, the fin roll is divided into three parts including the hole-shaped curved surface and rotates independently through the sleeve, sleeve, and bearing, and the dividing surface of the fin roll and side roll, which rotate independently through the sleeve, is By configuring the roll to be almost perpendicular to the curved surface of the mold, it is possible to prevent scratches on the strip, wear of the fin roll, chipping of the fin roll and side rolls, etc., and provide a long-life fin pass roll. is big.

[Brief explanation of the drawing]

FIGS. 1, 2, and 3 are sectional views of conventional fin pass rolls, and FIGS. 4 and 5 are sectional views of fin pass rolls of the present invention. 16: Fin, 17, 18: Intermediate roll, 2
0, 21: Side roll, 24: Needle bearing, 19, 30: Sleeve, 31 : Fin roll.

Claims (1)

[Scope of Claims] 1. A fin roll 31 and a side roll 20 engaged with a drive shaft during a process in the middle of forming a metal strip into a desired pipe through a large number of roll stands;
In the fin pass roll divided into 21 parts, a fin roll 31 is provided at the center of the hole shape of the fin pass roll, and the fin roll 31 is further sandwiched between the fins 16 and intermediate rolls 17 and 1 on both sides.
The side roll and the fin roll are divided into 8 parts having a shape including a hole-shaped curved surface, and are engaged with the drive shaft through a sleeve, while the contact surfaces of the side roll and the fin roll have a hole-shaped curved surface, and the cross section of the contact surface is approximately at right angles. The fin roll 31 is divided into fins 16 and intermediate roll 1.
A fine pass roll characterized in that 7 and 18 are configured to rotate independently. 2. The independently rotating fin roll according to claim 1, in which a bearing is fitted between the sleeve and the fin roll.