JPH033522B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a tube or bar rolling apparatus. Traditionally, pipes or rods (hereinafter referred to as tubes and rods) are manufactured using plastic processing methods such as rolling, extrusion, drawing, or forging, but each processing method alone has reached its technological limit, and dramatic advances are being made. Technical improvements are becoming increasingly difficult. SUMMARY OF THE INVENTION An object of the present invention is to provide a tube and rod rolling device that can greatly reduce the cross-sectional area using relatively small-sized equipment. To explain the present invention in detail, as shown in FIG. A rolling roll hole type path center line 8 is arranged in D2 and D3,
At least one of the ring rolls 4 is supported inside the gear 9 with the rotation axis K of the gear 9 and the center axis L of the ring roll hole type being different from each other, and the gear 9 is supported by a drive gear 14 connected to a drive source. This rolling device has a structure in which an eccentric rotational motion is given to the ring roll groove D2 by driving the ring roll. The gear 9 is rotatably supported on a bearing surface 12 of the housing 11. The case of rolling a bar using the apparatus of the present invention will be explained using the example shown in FIG. After rolling, the material is pressed and rolled between a ring roll mold which performs an eccentric rotational movement and ring roll molds before and after the ring roll mold. When rolling a pipe with the apparatus of the present invention,
When reducing the outer diameter of a pipe, the same procedure as for a rod is used, but when reducing the wall thickness along with the outer diameter, the first
As shown in the figure, a mandrel 6 is inserted into the tube, the tube 7 and the mandrel are introduced into a roll hole mold by a known device and rolled, and then an eccentric rotational movement is performed in the direction of the arrow 10. The pipe 7 is rolled while being pinched and pressed between the mold and the ring roll hole molds before and after the mold through the mandrel 6. In the apparatus of the present invention, it is preferable that the ring roll 4 is supported by a spherical surface Q2 inside the gear and is capable of tilting from a plane perpendicular to the pass center line 8 of the roll hole type. Furthermore, the centers R1, R2, and R3 of the minimum radius of the ring roll hole shape are shifted toward the exit side from the spherical centers SY, S2, and S3 of the ring roll bearing surface, respectively, and the spherical centers S1, R3 of the ring roll bearing surface are It is desirable that the intersections of the rolling reaction force vectors F1, F2, F3 and the ring roll rotation center axis are shifted toward the entry side with respect to S2 and S3. When material is rolled with such equipment, the direction of contact between the ring roll and the material is closest to the exit side, and as the gear rotates, the contact surface of the ring roll hole moves in the circumferential direction of the material. The new contact surface can advance toward the exit side, allowing the material to advance smoothly, and by tilting the ring roll, the shortest distance to the mandrel can be shortened to achieve a large wall thickness reduction. Can be done. When rolling a pipe in the apparatus of the present invention, the first
As shown in the figure, it is desirable to provide a device 15 for holding the mandrel 6 and controlling its speed on the entry side. This equipment allows the deformation of the tube to be controlled by controlling the feed rate of the mandrel. When rolling a bar, this device can be used as a bar pushing device, and can be rolled while applying a pushing force to the bar at the start of rolling or throughout rolling. In the apparatus of the present invention, it is desirable to provide rolling rolls 2, 2' for reducing the outer diameter on the exit side. This roll not only reduces the outer diameter of the pipe, but also improves the roundness, and by appropriately selecting the peripheral speed of this roll and the roll on the entry side, it applies a tensile force to the material, The material can be deformed smoothly. The outer diameter and wall thickness of the rolls on the exit side can be reduced in the range that the mandrel does not reach by applying a tensile force between adjacent roll molds arranged in a plurality of rolls like a stretch reducer. As shown in Table 1, under preferable rolling conditions for tubes using the apparatus of the present invention, a tube with an outer diameter of 40 mm and a wall thickness of 5 mm can be obtained at the exit of the equipment from a raw tube with an outer diameter of 80 mm and a wall thickness of 25 mm. In this case, the elongation rate (= cross-sectional area ratio) is 7.85
This is sufficiently large compared to the maximum elongation rate of 4 of the conventional 8-stand mandrel mill.

[Table] Conventional pipe rolling equipment, such as an 8-stand mandrel mill, completes all rolling using rolls, so it requires a large-diameter roll, a roll housing to hold it, a roll housing, a mill stand, and each drive unit. Required a motor. This means that the diameter of the roll increases in terms of roll strength, which results in an increase in the contact area of the rolls, which necessitates increasing the roll strength and the capacity of the entire rolling equipment. Since the ring roll hole mold and the pipe have a small contact area and can be deformed efficiently with a small force, the overall capacity of the equipment can be reduced. Although rolling stands of a conventional mandrel mill can be installed on the inlet and outlet sides of the apparatus of the present invention, most of the cross-sectional area reduction is done by the ring roll hole type.
The rolling apparatus can be made compact as a whole.

[Brief explanation of drawings]

FIG. 1 is a side cross-sectional view of the present invention, and FIG. 2 is a cross-sectional view taken from FIG. 1, 1'... Entrance side rolling roll, 2, 2'... Output side rolling roll, 3, 4, 5,... Ring roll, D1, D
2, D3...Ring roll hole type, 6...Mandrel,
7... Pipe, 8... Rolling roll path center line,
9...Gear, 10...Gear rotation direction, C1...Inlet side rolling roll hole type, C2...Outlet side rolling roll hole type, 12
...Gear bearing surface by housing, Q1, Q2, Q
3...Ring roll bearing surface, R1, R2, R3...
Minimum radius of ring roll hole type, S1, S2, S3
... Spherical center of ring roll bearing surface, 14... Drive gear, 15... Mandrel control device.

Claims (1)

[Scope of Claims] 1. Following a rolling roll forming a groove, one or more ring rolls are disposed therein, each having a groove having relief at the edge and including a pass center line of the rolling roll. at least one of the ring rolls is tiltably supported by a spherical surface of the inner diameter part of the gear with a rotation center axis different from that of the gear, and the ring roll hole shape is formed by the rotational drive of the gear. A tube and rod rolling device configured to impart eccentric rotational motion to the tube. . 2. The method according to claim 1, characterized in that the intersection position of the minimum inner diameter of the ring roll hole type and the pass center line of the rolling roll is biased toward the exit side from the spherical center position of the ring roll bearing surface. Tube and bar rolling equipment. 3. The tube and rod rolling apparatus according to claim 1 or 2, wherein a device for holding the mandrel and controlling its speed is provided on the entry side. 4. The tube and rod rolling apparatus according to any one of claims 1 to 3, wherein a rolling roll for reducing the outer diameter is disposed on the exit side.