JPS5890305A - Method and device for replacing stand of rolling mill - Google Patents

Abstract

PURPOSE:To improve the working efficiency of the entire part and to reduce the restrictions on the spacings between stands by half by installing stand placing frames on the side of a stand train continuously on two moving devices of different stroke lengths and providing horizontal moving devices on the sides of the new and old stands on both sides of the frames. CONSTITUTION:Old stands US1, US3 are moved on a frame A by moving devices B1, B3, then the frame A is moved up to the position +p by a stand moving device C. New stands NS1, NS3 are moved onto the frame A by moving devices B1', B3' and are withdrawn onto a pass line PL by the B1, B3. Here the frame A is moved again to the origin. If the output of a stand moving device D is beforehand increased, the frame A is pushed and is positioned accurately. The reafter, the US2 and US4 are placed on the frame A, and are moved to the position -p. If the D is moved beforehand, the movement of the frame A is not interfered. After the NS2, NS4 are moved onto the line PL, the frame A is returned to the origin. If at this time the D is held pressed at the origin by moving the C, D simultaneously, the positioning is completed.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rolling stand exchanging method in a continuous rolling mill train and an exchanging device used therein.

For example, in the case of a row of forming stands for welded steel pipes, it is necessary to change the rolls every time the forming pipe diameter is changed. The conventional method for changing rolls is to use a crane to change each roll assembly on a pass line using an open-head mill, but this process not only takes a long time, but also requires a long time to assemble the rolls. During the changeover, line operations will be halted, and a great deal of effort will be expended, which will inevitably result in a decrease in production. - In order to compensate for the above drawbacks, prepare a spare stand with a new roll assembly installed in advance and place it on a pedestal that can move parallel to the line, and when replacing the stand, place the old stand on the pedestal. Move it to.

Next, move the pedestal in a direction parallel to the pass line.

A method has been implemented in which a spare stand with a new roll is placed on the pass line (2) and the old and new stands are exchanged. However, in this method, multiple stands are exchanged at the same time. However, there was a drawback in that the intervals between the stands on the pass line had to be widened to maintain a constant yield.

The present invention relates to a stand exchanging method proposed for the purpose of eliminating the drawbacks of the conventional stand exchanging method described above, and an apparatus for implementing the method.

The present invention will be specifically described below with reference to the drawings.

Figure 1 shows the conventional stand replacement method, showing the old stand USI, US2. −． Urn is mounted on the stand mounting frame A arranged parallel to the pass line using a moving device B (such as a σ hydraulic cylinder), and then the stand mounting frame A (purple) is placed in a direction parallel to the pass line. , is moved by p by the moving device C, and a new roll is placed in advance (on the upstream side in the figure) to create new stands NSI, NS2. −．
NSN.

Use the moving device B to push onto the pass line.

This completes the stand replacement.

In this method, if a plurality of stands are to be replaced at the same time, the stand interval P must be equal to or greater than twice the moving distance p of the mounting frame A. That is, the relationship P≧2p must be satisfied.

FIG. 2 shows a conceptual diagram of the recombination system of the present invention.

In the figure, the old stand USI is on the pass line.

Assume that UO3 is replaced with new offline stands NSI and NS2.

First, move the USI onto the stand mounting frame A (
(Fig. 2(a)), then move it upstream by p.

Move NSI from offline to pedestal A (
Figure 2(b)). After further moving NSI onto the pass line, gantry A is moved downstream by p (that is, returns to the initial position), and USI is moved offline, completing the replacement of NSI and USI.

At the same time, move UO3 onto stand A (see Figure 2 (C).
)). Move gantry A again downstream this time by p, and
Move S2 from offline to mount A and then to the pass line (Fig. 2 (d)), move mount A upstream by p, move UO3 to offline, and move NS2 and UO3. The replacement is also completed (FIG. 2(e)).

Therefore, the moving distance of the gantry A is 2p, but if P≧p, this method is valid.

The recombination method has been explained above in the case of two stands, but in the case of three or more stands, the above NSI and USI are changed to odd-numbered stands (NSI, N, S3..., USI, UO3゜...
), NS2. UO3 to even numbered Steid (NS2
．． NS4. ..., UO3, UO4,...).

Here, determine the position when moving the stand mounting frame A (if there are two, the first position is the origin, and the downstream side is (+
) direction, upstream 111! If I k (-) direction, -
It is necessary to move the stand at the three points +p・0 and -p (-), and accurate positioning is required at each point.

Positioning at 10p and -p can be easily achieved by accurately arranging a mechanical stopper, but positioning at the origin poses a problem.

If a mechanical stopper is provided, the stand will be +p
Since it moves from to -p, it must have a structure that allows it to be saved. There is also a method of using electrical sensors (limit switches, etc.), but problems remain in terms of accuracy and reproducibility. There is also a method of moving the pedestal using a moving device (such as a two-stage cylinder) that is capable of positioning in multiple positions.

The disadvantage is that it is expensive.

Therefore, in the present invention, for positioning at the origin, a moving device capable of moving the pedestal from +p to -p, that is, a device having a stroke p is attached to a hydraulic cylinder or the like having a stroke of 2p. .

This device is capable of suppressing the pedestal, and by pressing the pedestal at the origin, it is possible to accurately position the pedestal at the origin.

An embodiment of the device of the present invention is shown in Figs. 3 and 4 (Fig. 3a).
-a' cross section). FIG. 3 shows a row of rolling mills consisting of four rolling mills. A device C for moving the stand mounting frame A from 10p to -p is provided with a device for positioning, and FIG. 1 shows the positioning situation at the origin.

81 to B4 are devices for moving the stand on the pass line onto the pedestal A.

B1' to B4' are devices for moving the offline stand onto the pedestal A, and these devices have a force mechanism capable of moving in the opposite direction.

By the recombination method of the present invention, the old stand U is first placed on the pedestal A.
SI and Us3 are moved by the moving devices Bl and B3, and then the gantry moving device C moves the gantry A to the +p position #. Then, the new stands NSI and NS3 are moved onto the mount A by the moving devices Bl' and B3', and further pulled onto the pass line by the moving devices Bl and B3. Here, pedestal A is moved to the origin again, but at this time, if the output of positioning device C is made thicker than the output of pedestal moving device B, the pedestal will be pressed at the origin and accurate positioning will be possible. .

Next, Us2. Us4 is placed on pedestal A and moved to position -p, but if D is moved in advance, movement of pedestal A will not be hindered. NS2. After moving NS4 onto the ζ line, mount A is returned to the origin, but
At this time, one positioning is completed by moving C and D at the same time and placing D in a suppressed state at the origin.

As described above, according to the stand exchange method of the present invention, the drop in production due to zero exchange is reduced, and the time for one rearrangement itself is distributed within the working time, so the overall work efficiency is improved and the stand spacing is limited. will be halved.

With the exchanging device of the present invention, the above exchanging method can be implemented with high accuracy and at low cost.

Incidentally, here I have written about the case where the present invention is applied to a row of forming stands for welded steel pipes.

It can also be applied to rolling mills that have a stand exchange system including an inner stand exchange system.

[Brief explanation of drawings]

FIG. 1 is a plan view showing a conventional stand replacement method, FIG. 2 is a conceptual diagram of a replacement method according to the present invention, and FIG. 3 is a flat view showing an embodiment of the present invention. FIG. 4 is a sectional view taken along line a-a' in FIG. 3. A; Stand mounting frame B; Stand moving device C; Stand mounting frame D; Positioning device moving device p
; Stand mounting frame P; Stand interval Travel distance

Claims (1)

[Claims] 1. When replacing a rolling mill stand, a stand mounting pedestal is arranged on the side of a row of at least two rolling mill stands, and the pedestal is connected to a horizontal moving device to replace the rolling mill stand. At the same time, the required number of new rolling mill stands are placed on the side of the stand mounting frame, and the old and new rolling mill stands are moved horizontally in a direction perpendicular to the pass line direction. It is possible to use a stand mounting frame.
A rolling mill stand that makes it possible to replace the old and new rolling mill stands by repeatedly moving forward and backward at a fixed pitch in the direction of the pass line, and then sequentially moving the Takeda stand in a direction perpendicular to the pass line in accordance with the advanced and retreating positions. method of exchange. 2. A stand mounting frame is arranged on the side of at least two or more rolling mill stands, and the stand is connected to two moving devices having different stroke amounts, and the stand mounting frame is arranged on both sides of the stand mounting frame. , A rolling mill stand exchange device in which horizontal movement devices are arranged on the sides of the old and new rolling mill stands, which are placed adjacent to each other, and the old and new rolling mill stands can be exchanged.