JPH03198939A - Ring rolling mill - Google Patents

Abstract

PURPOSE:To form a discontinuous projecting part, etc., in the peripheral direction of the outer peripheral surface of a stock by providing a split die and a cylindrical outer frame on the outer peripheral surface of the stock and rolling the stock with the split die and the outer frame, when a ring-like stock is rolled between a main roll and a auxiliary roll. CONSTITUTION:When a ring-like stock A is rolled between a main roll 11 and an auxiliary roll 12, a mandrel sleeve 14 is fitted to the inner peripheral surface of the stock A. The split die 15 to form the outer peripheral surface of the stock A and the cylindrical outer frame 16 to hold the split die 15 in the annular form are prepared and the split die 15 is divided into two parts in the peripheral direction so that they can form a cylindrical form and has step parts 16a and the outer frame 16, too, forms step parts 15b. The heated split die 15 and the outer frame 16 are engaged through the step parts 16a, 15b and while the stock A is inserted into the split die 15, the main roll 11 is rotated and the auxiliary roll 12 is moved to roll the stock A. In this way, when a discontinuous ruggedness is formed in the peripheral direction of the inner peripheral surface, discontinuous projecting and recessed parts can be formed in the peripheral direction of the outer peripheral surface.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a ring rolling mill that further rolls a ring-shaped material into a ring shape.

[Prior Art] Conventionally, as this type of ring rolling mill, the one shown in FIG. 4, for example, is known.

That is, a ring-shaped wall of the material is sandwiched between a main roll 1 and a mandrel (auxiliary roll) 2 arranged parallel to the rotation axis of the main roll 1, and the mandrel 2 is placed on the main roll 1 side. By rotating the main roll 1 while pressing, the material A is further rolled.

By providing circumferentially uniform annular protrusions and four parts on the outer peripheral surface of the main roll and mandrel, uniform annular protrusions and recesses are formed in the circumferential direction on the outer and inner peripheral surfaces of material A. can do.

[Problem to be solved by the invention] However, in the above conventional ring rolling mill,
If you try to form protrusions or recesses that are discontinuous in the circumferential direction on the outer peripheral surface of material A, the relative position of the main roll and material A will shift as the rolling progresses, so it is difficult to form the protrusions etc. neatly. The problem was that I couldn't do it.

For this reason, when forming discontinuous convex portions or the like on the outer circumferential surface of the material A, it has generally been done by machining. However, in order to form the convex portion, all parts other than the convex portion must be scraped off, which has the drawback of extremely low yield.

Therefore, it has been desired to develop a ring rolling mill capable of forming discontinuous convex portions on the outer peripheral surface of a material.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a ring rolling mill capable of forming discontinuous convex portions and the like on the outer peripheral surface of a material.

[Means for Solving the Problems] In order to achieve the above object, the present invention includes a main roll and a sub roll provided opposite to the main roll, and the main roll and the sub roll A ring rolling mill that presses the wall surface of a ring-shaped material to roll the material into a ring shape, includes a split die provided to surround the outer circumferential surface of the material, and a split die that is tightly attached to the outer circumferential surface of the split die. A cylindrical outer frame is provided to hold the split molds in an annular shape, and the material is rolled together with the split molds and the outer frame.

[Operation] In the present invention, the outer circumferential surface of the material is rolled so as to follow the irregularities of the inner circumferential surface of the split die by compression between the main roll and the sub-roll. Therefore, for example, by forming circumferentially discontinuous protrusions or four parts on the inner circumferential surface of the split mold, it is possible to form irregularities corresponding to these protrusions or four parts on the outer circumferential surface of the material. Furthermore, after rolling the material, the rolled material can be easily taken out by removing the split die from the outer frame.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

In Figures 1 and 2, 11 is a main roll;
12 is a mandrel (auxiliary roll). The main roll 11 is provided so as to be rotatable around its axis. The mandrel 12 is arranged so that its axis is parallel to the axis of the main roll 11, and is configured to be able to rotate freely around the axis, and is driven to move toward and away from the main roll 11. It is now possible to do so.

A rolling jig 13 for rolling the ring-shaped material A is provided between the main roll 11 and the mandrel 12.

This rolling jig 13 includes a mandrel sleeve 14 for forming the inner circumferential surface of the material A, a split die 15 for forming the outer circumferential surface of the material A, and an outer frame 16 for holding the split die 15 from the outside in the radial direction. It is prepared.

The mandrel sleeve 14 is formed into a cylindrical shape, and is adapted to be rotatably fitted onto the mandrel 12. Further, a stepped portion continuous in the circumferential direction is formed on the outer peripheral surface.

The split die 15 is a cylindrical piece having an inner diameter slightly larger than the outer diameter of the raw material A before rolling, and is divided into two pieces at positions shifted by 180 degrees in the circumferential direction.

The inner circumferential surface of the split mold 15 is formed with a circumferentially continuous step and a circumferentially discontinuous recess 15a as shown in FIGS. 2 and 3. Furthermore, a stepped portion 15b is formed on the outer circumferential surface of the split mold 15 to define the position of the outer frame 16 in the axial direction.

The outer frame 16 is formed in a cylindrical shape, and has a stepped portion 1 on its inner circumferential surface that engages with the stepped portion 15b of the split mold 15.
6a is formed. The outer peripheral surface of the outer frame 16 is formed into a cylindrical shape.

In the ring rolling mill configured as described above, the material A and the split mold 15 are heated in a furnace. In this case, it is preferable to heat the split mold 15 to a higher temperature than the material A. Then, the split mold 15 is inserted into the outer frame 16 and held in a cylindrical shape, and with the material A inserted into the split mold, the material A is rolled between the mandrel 12 and the main roll 11. At this time, the mandrel 12 is moved toward the main roll 11 while the main roll 11 is rotationally driven.

Then, the material A is rolled by the mandrel sleeve 14 and the split mold 15, and the inner peripheral surface of the material A follows the shape of the outer peripheral surface of the mandrel sleeve 14, and the outer peripheral surface of the material A also follows the shape of the inner peripheral surface of the divided mold 15. Follow the shape of the surface.

After forming the material A, the material A is taken out together with the outer frame 16, and the split mold 15 is pushed out from the outer frame 16. As a result, the split mold 15 is separated and the material is taken out from inside.

In the ring rolling mill configured as described above, the split mold 15 can be divided, so that the raw material A having protrusions and recesses formed on the outer peripheral surface can be easily taken out from the split mold 15. Therefore, it is possible to easily form convex portions or concave portions on the outer circumferential surface of the ring-shaped material A by rolling, which is a remarkable effect.

Moreover, since the split mold 15 is held by the outer frame 16, the split mold 15 can be reliably held in a cylindrical shape. Therefore, there is also an effect that the material A can be precisely molded.

Furthermore, the split mold 15 should be the same as material A or 20 to 30
By heating at a temperature as low as 0'C, heat radiation can be prevented from the material A, and the material A can be easily rolled and formed at a constant temperature.

In the above embodiment, the main roll 11 is configured to be rotationally driven, but it goes without saying that the auxiliary roll 12 may be rotationally driven.

Further, the mandrel sleeve 14 and the outer frame 16 may also be heated before rolling.

Furthermore, although the split mold 15 is configured to be divided into two parts at 180° positions, it goes without saying that it may be further divided into any shape at multiple positions.

[Effects of the Invention] As explained above, according to the present invention, the present invention includes a main roll and a sub-roll provided opposite to the main roll, and between the main roll and the sub-roll. A ring rolling mill that presses the wall surface of a ring-shaped material to roll the material into a ring shape includes a split mold provided so as to surround the outer circumferential surface of the material, and a split mold that is placed in close contact with the outer circumferential surface of the split mold to roll the material into a ring shape. A cylindrical outer frame that holds the split mold in an annular shape is provided, and the material is rolled together with the split mold and the outer frame, so that discontinuous irregularities are formed in the circumferential direction on the inner peripheral surface of the split mold. By doing so, it is possible to form circumferentially discontinuous convex portions or concave portions on the outer circumferential surface of the material.

After rolling the material, the material can be easily taken out by removing the split die from the outer frame and dividing the material.

Therefore, it is possible to form convex portions or four portions that are discontinuous in the circumferential direction on the outer peripheral surface of the ring-shaped material by rolling, which is a remarkable effect.

[Brief explanation of drawings]

Figures 1 to 3 are views showing an embodiment of the present invention, in which Figure 1 is a side view of the main parts of a ring rolling mill, and Figure 2 is a side view of the main parts of the ring rolling mill. FIG. 3 is a cross-sectional plan view taken along line Ill-1 in FIG. 2, and FIG. 4 is a cross-sectional side view of a main part of a ring rolling mill shown as a conventional example. 11...Main roll, 12...Mandrel (secondary roll), 15...
...Divided type, 16...Outer frame, A...Material.

Claims (1)

[Scope of Claims] Comprising a main roll and a sub-roll provided opposite to the main roll, the wall surface of the ring-shaped material is pressed between the main roll and the sub-roll to form a ring-shaped material. A ring rolling mill that rolls a material into a ring shape includes a split mold provided to surround the outer peripheral surface of the material, and a cylindrical outer mold that tightly contacts the outer peripheral surface of the divided mold to hold the divided mold in an annular shape. A ring rolling mill characterized in that a frame is provided, and the material is rolled together with the divided molds and the outer frame.