JPS6356307A - Method for controlling pressing force of grinding belt of roll grinder - Google Patents

Abstract

PURPOSE:To improve the life of a grinding belt by increasing the pressing force of the grinding belt to a roll in accordance with the adequate pressing force of the grinding belt to the roll from the relation between roll grinding tie and stock removal. CONSTITUTION:The adequate pressing force corresponding to the grinding time is preliminarily stored in the sequencer (or minicomputer) of a roll grinder 50. A fluid pressure cylinder 24 is controlled by the command of the sequencer at the time of roll grinding. The data by kinds of the grinding belt and by materials of the roll to be ground are preliminarily stored. Not only the life of the belt is improved but also the productivity is improved by the above- mentioned method.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a grinding belt pressing force control method for a medaka roll grinding device that effectively uses the grinding belt in the roll grinding device for a long period of time.

[Conventional technology]

Rolling is performed by squeezing the material to be rolled between a pair of upper and lower work rolls and rolling it down due to the frictional force generated between the work rolls and the material to be rolled. Continued use will gradually cause wear and tear and rough skin. Since abrasion and roughness on the roll surface greatly affect the shape and profile of the rolled strip, it is necessary to perform scheduled rolling and periodically grind the work roll to avoid defects in the shape and profile of the strip. There is.

However, this roll grinding work is generally carried out by taking the rolls out of the rolling mill and transporting them to a roll shop, so the rolling line has to be stopped frequently to rearrange the rolls, resulting in a problem of poor productivity. Therefore, for example, JP-A-59-156507 and JP-A-58-163509
The publication proposes disposing a roll grinding device equipped with a grinding belt in a rolling mill to grind the rolls during rolling through the mill without interrupting the rolling operation.

[Problem that the invention attempts to solve]

However, in such conventional roll grinding methods, the grinding belt is pressed against the roll with a certain force by a fluid pressure cylinder for grinding, so as the grinding time elapses, the grinding The abrasive grains on the belt also wear out, and the surface of the grinding belt becomes flat, resulting in curve A + in Figure 4.
, As shown in A2, the result is that the grinding does not proceed after a certain period of time.

Therefore, as a countermeasure to this problem, it is possible to make the grinding belt extremely long and extend the grinding time, but even if the grinding belt is made long, there is a limit to the space on the reel that stores it in a cassette type, or the grinding progresses too slowly. It is difficult to replace a worn-out grinding belt during rolling, and the grinding belt reaches the end of its life when grinding stops progressing.
There were problems in that the rolling operation had to be stopped for a long period of time to replace it, or the mill had to be replaced using a idle mill.

This invention was made in view of such conventional problems, and in order to extend the life of a grinding belt of a certain length, that is, the usable time, the pressing force of the grinding belt against the roll is controlled. The aim is to solve the above problems by adopting a method to do so.

[Means for solving problems]

This invention selects an appropriate pressing force of the grinding belt against the roll corresponding to the roll grinding time from the relationship between the roll grinding time and the roll grinding amount by the grinding belt of the roll grinding device, and based on this, the grinding belt is pressed against the roll of the grinding belt. This is a grinding belt pressing force control method that increases the pressing force on the grinding belt.

[Effect]

When grinding a roll using a roll grinding device equipped with a grinding belt, the grinding amount of the grinding belt on the roll corresponding to the roll grinding time should not be reduced due to the change in the amount of roll grinding as the roll grinding time elapses. If you select an appropriate pressing force and increase the pressing force of the grinding belt in proportion to the grinding time based on this, the amount of grinding will not decrease even if the grinding time elapses, and as a result, the grinding speed will increase. The life of the belt can be extended and therefore the frequency of shutdowns for replacing the abrasive belt can be minimized.

〔Example〕

The present invention will be explained below based on the drawings. 1 to 4 are diagrams for explaining the present invention in detail. FIG. 1 is a schematic diagram of a roll grinding device to which the present invention is applied installed in a rolling mill, and FIG. FIG.

First, the roll grinding device 50 will be explained.

In the figure, 10 is a rolling mill, 11 is a housing post of the rolling mill, and a guide beam 12.13 is installed between the housing posts on the entry side of the work roll 1a and parallel to the work roll 1a. . 14 is a traverse frame provided movably on the guide beams 12 and 13. 15.16 is the guide beam 12.1
A sprocket 1-17, 18 is fixed near both ends of this shaft, and a chain 19-19 is stretched around the sprocket. Further, the shaft 16 is connected to a motor 21 via a gear box 20, and a position detector 22 is connected to the motor 21.

The chain 19 and the traverse frame 14 are connected by claws 23 near each of the guide beams 12 and 13, and when the chain 19 is rotated by the motor 21, the traverse frame 14 can be moved parallel to the work roll la axis. It looks like this.

A grinding head 3 composed of a platen 4 and guide rolls 5 arranged above and below the platen is provided on a traverse frame 14 so as to be able to approach and separate from the work roll 1a, and the grinding head 3 is attached to a fluid pressure cylinder 24. It is being This fluid pressure cylinder 24 is controlled by a sequencer (or minicomputer) not shown, and the pressing force of the grinding heel 3 against the work roll 1a is controlled by the fluid pressure of the fluid pressure cylinder 24 according to the commands of this sequencer. It is meant to be given.

Reference numeral 25 denotes a reel storage section, which is attached to the traverse frame 14 so as to extend above and below the fluid pressure cylinder 24, and whose side surface facing the cartridge holder 26 is open.
In addition, mandrels 27 and 27 are provided above and below the fluid pressure cylinder 24.
is provided.

Reels 28 and 28 are attached to the main shaft of the mandrel 27 and are rotated by a motor 29. A grinding belt 6 is wound around these reels 28, 28, and this grinding belt is connected to the guide roll 5, as described above. It is hung around the platen 4.

A cartridge holder 26 is provided at the end of the guide beam 12, and the cartridge 30 can be positioned and placed on this holder 26.

31 is a cooling water header, and cooling water is injected onto the work roll 1a from a nozzle 32 of this header.

Reference numeral 7 denotes a wiper for removing grinding debris generated when the work roll 1a is ground so as not to get caught between the work roll 1a and the material S to be rolled.

In the above configuration, the grinding head 3 is pressed against the rotating work roll 1a by the fluid pressure cylinder 24, while the motor 29 is started to move the grinding belt 6 wound around the reel 28 to the guide roll 5 and the platen 4. Grinding of the work roll 1a is performed by rotating the work roll 1a slowly through the work roll 1a.

Further, a roll grinding device 50 attached to the traverse frame 14 placed on the guide beam 12.13 is
Since the work roll 1a can be moved in parallel along the body length direction by starting the motor 21, grinding can be performed over the entire length of the work roll 1a.

Here, the lifespan until the grinding head 6 loses its grinding ability is that if the pressing force against the work roll 1a is kept constant, the grinding ability decreases over time and approaches zero after a certain time. The apparent lifespan ends. However, in reality, the grinding ability of the grinding belt is not lost at this point, and experiments have shown that if the above-mentioned pressing force is increased, the grinding power of the abrasive grains of the grinding belt is restored.
It has been confirmed as shown in Figure 4. The grinding belts used in the experiment were 25 m long and 40 m wide.
0 size 2 grain size #150. The material of the work roll is high chrome cast iron.

Now, the pressing force is AI -300kg for the grinding time,
When Az = 800kg, and B
When the weight is varied from 100 to 800 kg (see Figure 3), the amount of roll grinding (the amount of roll grinding waste is changed to c
In AI and A, the grinding capacity appears to be a little large at the beginning, but it reaches its maximum value (approximately 1500cc) in 3 to 4 hours.
), it no longer increases at all, indicating that the grinding ability has been lost.

On the other hand, in B, the amount of roll grinding continues to increase in proportion to the increase in pressing force, indicating that the grinding capacity (cc/min) remains almost constant until the true life of the grinding belt ends ( (See Figure 4).

Therefore, in the embodiment, a sequencer (or minicomputer, not shown) of the roll grinding device 50 stores a value at which the pressing force changes linearly as shown in B in FIG. During roll grinding, the fluid pressure cylinder 24 is controlled by commands from this sequencer.

In practice, data as shown in Figure 3.4 is prepared for each type of grinding belt and material of the roll to be ground so that it can be applied to each stand of the rolling mill.

〔Effect of the invention〕

As explained above, according to the present invention, an appropriate pressing force of the grinding belt to the roll corresponding to the grinding time is selected from the relationship between the grinding time by the grinding belt and the amount of roll grinding, and the grinding is performed based on this. By using a grinding belt pressing force control method that increases the pressing force of the belt against the roll, the apparent life of the grinding belt is extended to its true life, thereby reducing the unit consumption of the grinding belt, and further reducing the need for replacing the grinding heald. Since the frequency of stopping the rolling operation can be extremely reduced, productivity can be greatly improved.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of an embodiment according to the present invention, Fig. 2 is a view taken along arrow nn in Fig. 1, Fig. 3 is a diagram showing the relationship between pressing force and grinding time in the embodiment, and Fig. 4 is a roll grinding diagram. Relationship diagram between amount and grinding time. 1a... Work roll, 6... Grinding belt, 10... Roll grinding device.

Claims (1)

[Claims] From the relationship between the roll grinding time and roll grinding amount by the grinding belt of the roll grinding device, select the appropriate pressing force of the grinding belt against the roll corresponding to the roll grinding time, and based on this select the pressing force of the grinding belt against the roll. A grinding belt pressing force control method for a roll grinding device characterized by increasing the