JPH0149577B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a roundness control device in a ring rolling mill.

BACKGROUND OF THE INVENTION Various types of ring rolling mills are used to hot-roll a metal ring that has been rough-processed using a press machine. For example, ring rolling mills manufactured by William Totsudo and Edgewater in the United States have inner and outer rolls that press the roughened ring material in the width direction from the inside and outside, and are installed at opposite positions in the diametrical direction of the ring material. A rolling device is constituted by upper and lower rolls that roll the ring material from above and below, and a total of 4 guide rolls, one each provided before and after the two rolls, and the rolling of the ring material is carried out. Centering of the ring material is performed by retracting the upper and lower rolls and the guide roll as the diameter increases. In addition, the ring rolling mill manufactured by Wagner AG in West Germany reduces the number of guide rolls by half and places one on each side of the inner and outer rolls, and detects the pressure difference between the rings acting on the left and right guide rolls. It is configured to automatically center the ring material by controlling the rotational speed of the upper and lower rolls.

Problems to be Solved by the Invention However, the above ring rolling mill is accompanied by various practical limitations. That is, in the former case, a high degree of skill is required to properly control the pressure of the ring material acting on the guide roll, and in the latter case, a high degree of skill is required to control the position and retraction distance of the guide roll, and In order to control the relative position of the ring material to the upper and lower rolls, which are far away from the guide rolls, a complex control system has had to be employed. Due to this reason, the roundness of the ring material is often impaired, and in order to avoid this inconvenience, it is necessary to add extra allowance for grinding the ring material in anticipation of a certain degree of deviation in the roundness. I had to add it to It is easy to understand that this method involves other problems in promoting resource saving effects and improving productivity.

The main objects of the present invention are to provide a simple structure that can solve the above-mentioned problems observed in conventional ring rolling mills, and to improve roundness in a ring rolling mill with excellent operation reliability. The purpose of this invention is to provide a control device.

Means for Solving the Problems In view of the above object, the present invention provides a first rolling means consisting of a mandrel roll and a main roll disposed opposite to each other on the inner and outer circumferential surfaces of a ring-shaped workpiece, and In a ring rolling mill having a second rolling means consisting of an upper etching roll and a lower etching roll arranged opposite to each other on the end face, the main roll is arranged on the left and right sides of the main roll in an axial direction parallel to the main roll. A first guide roll and a second guide roll that press the ring-shaped workpiece are arranged opposite each other, and the first guide roll and the second guide roll move backward according to changes in the outer diameter of the ring-shaped workpiece. A fixed block whose position can be freely adjusted is disposed at the outer end of the path, and the first guide roll and the second guide roll that have reached the final retracted position are attached to the fixed block according to the maximum outer diameter of the ring-shaped workpiece. The gist of this invention is a roundness control device in a ring rolling mill configured to support the ring rolling mill.

Function Since the first guide roll and the second guide roll contact the fixed block whose fixed position is regulated by the maximum outer diameter of the ring-shaped workpiece in their final retracted position, these guide rolls and the rolling The relative position to the roll can be controlled accurately and quickly. Therefore, even if the workpiece is rolled into a somewhat elliptical shape during rolling, the roundness of the ring-shaped workpiece finally obtained is maintained at a good level.

Embodiment FIG. 1 is a plan view illustrating a roundness control device for a ring rolling mill according to the present invention. As shown in the figure, the ring rolling mill R includes a first rolling means consisting of a mandrel roll 2 and a main roll 3, which are arranged opposite to the inner and outer peripheral surfaces of the ring-shaped work 1, and a first rolling means which is arranged opposite to the upper and lower end surfaces of the ring-shaped work 1. A second rolling device is provided, which includes a frusto-conical upper etching roll 4 and a lower etching roll (not shown). On the left and right sides of the main roll 3, there are a first guide roll 5a and a second guide roll 5b, which press the outer peripheral surface 1a of the ring-shaped workpiece 1 with their axes aligned with the main roll. They are arranged symmetrically in pairs. The first guide roll 5a and the second guide roll 5b apply pressure in the normal direction to the outer peripheral surface of the ring-shaped workpiece 1 in accordance with changes in the outer diameter of the ring-shaped workpiece 1 as the rolling process progresses. retreat along its radial direction. On the other hand, at the outer ends of the movement paths of the first guide roll 5a and the second guide roll 5b, fixed blocks 6a and 6b whose positions are freely adjustable are disposed. The fixed position of the fixed block is such that it comes into contact with the first guide roll 5a and the second guide roll 5b at the final retreat position Rmax calculated from the maximum outer diameter of the ring-shaped workpiece 1. Selected.

The ring-shaped workpiece 1 is heated to a predetermined hot rolling temperature and supplied to the ring rolling mill R. In this state, a main roll 3, a mandrel roll 2, and upper and lower edge rolls (only the upper edge roll has a reference number 4) are heated to a predetermined hot rolling temperature. ) to obtain a maximum diameter D in the width direction and in the axial direction. In this hot rolling process, the first guide roll 5a and the second guide roll 5b move as the diameter of the ring-shaped work 1 increases.
It retreats while applying pressure to the outer circumferential surface of the roller, and reaches the final retreat position Rmax at the end of rolling. A hydraulic cylinder device or the like is connected to the guide rolls 5a and 5b as means for pressurizing the ring-shaped workpiece 1.
On the other hand, the fixed blocks 6a and 6b are provided with a gap adjustment device (not shown) such as a manual feed mechanism or an automatic feed screw mechanism as means for adjusting the relative arrangement position with respect to the guide rolls 5a and 5b.
When the contact position between the guide rolls 5a, 5b and the fixed blocks 6a, 6b is calculated by the computer attached to the ring rolling mill R based on the maximum diameter D of the ring-shaped workpiece 1, the gap adjustment device is activated. Then, the fixed blocks 6a, 6b are moved to predetermined positions. The first guide roll 5a and the second guide roll 5b move backward as the diameter of the ring-shaped work 1 increases while applying pressure to the outer peripheral surface of the ring-shaped work 1, and at the end of rolling, the first guide roll 5a and the second guide roll 5b move back to the final position Rmax.
It reaches and abuts against the fixed blocks 6a, 6b, and is firmly supported so as not to move back any further. In this case, just before the ring-shaped workpiece 1 acquires the maximum diameter D, the oil passage of the hydraulic cylinder device is switched, and the state of pressing against the outer peripheral surface of the ring-shaped workpiece 1 changes to the state of pressing against the pressure-receiving surfaces of the fixed blocks 6a and 6b. A method of changing the biasing direction of the first guide roll 5a and the second guide roll 5b to obtain the final retreat position Rmax, or a method of guiding the ring-shaped workpiece 1 while applying a predetermined pressing force to the outer peripheral surface thereof. roll 5
It is possible to adopt any of the methods of pressing a and 5b against the pressure receiving surfaces of the respective fixed blocks 6a and 6b to obtain the final retreat position Rmax.

Effects of the Invention As can be understood from the above explanation, the first guide roll and the second guide roll are fixed in a fixed block whose fixed position is regulated by the maximum outer diameter of the ring-shaped workpiece in their final retracted positions. The relative positions of these guide rolls and rolling rolls can be accurately and quickly controlled. Therefore, even if the workpiece is rolled into a somewhat elliptical shape during rolling, the roundness of the final ring-shaped workpiece is maintained at a good level. Thus, the present invention can significantly exceed the level of conventional equipment in terms of reducing grinding stock and improving productivity due to improved roundness.

[Brief explanation of drawings]

FIG. 1 is a plan view illustrating a roundness control device for a ring rolling mill according to the present invention. 1... Ring-shaped work, 2... Mandrel roll, 3... Main roll, 4... Etching roll, 5... Guide roll, 6... Fixed block,
Rmax...Final retreat position of the guide roll, D...
Maximum diameter of ring-shaped workpiece, R...Ring rolling machine.

Claims (1)

[Claims] 1. A first rolling means consisting of a mandrel roll and a main roll arranged opposite to each other on the inner and outer circumferential surfaces of a ring-shaped workpiece, and an upper etching roll and a lower etching roll arranged oppositely to the upper and lower end surfaces of the ring-shaped workpiece. In a ring rolling mill having a second rolling means, first guide rolls and second guide rolls on the left and right sides of the main roll press the ring-shaped workpiece with the axial direction parallel to the main roll. are arranged opposite to each other, and a fixed block whose position can be freely adjusted is disposed at the outer end of the movement path of the first guide roll and the second guide roll, which move backward according to changes in the outer diameter of the ring-shaped workpiece. A ring rolling mill characterized in that the first guide roll and the second guide roll, which have reached the final retreat position according to the maximum outer diameter of the ring-shaped workpiece, are supported by the fixed block. Control device for roundness.