JPH0318004Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention is based on a cooling water drainage function of a work roll installed on the rear pass line of a hot rolling mill for steel plates, and a work roll for rolling material. The present invention relates to a device having a function of preventing the tip from curling upward.

(Prior Art) In a rolling mill for steel plates, it is important for the tip of the material to be rolled to be within a predetermined height from the pass line on the exit side of the rolling mill to ensure good operability for the next process (for example, This is one important condition for ensuring good engagement with subsequent rolling mills, shearing machines, pinch rolls, winding machines, etc.). The cheapest and most reliable way to satisfy this condition is to use a guide or the like to straighten a product that has warped to a height higher than the specified value.

On the other hand, in hot rolling mills for steel plates, the purpose is to prevent thermal expansion due to heat transfer from the rolled material, to prevent thermal cracking that occurs on the roll surface due to contact with high-temperature materials, or to prevent roll surface roughening. , cooling water is usually sprayed on the surface of the work roll. However, if this cooling water stagnates on the upper surface of the material to be rolled after cooling the work rolls, it cools the material to be rolled and becomes a hindrance in terms of energy saving and ensuring quality of the material, so it is necessary to eliminate this problem. The most effective way to do this is to skim off the waste water after cooling the work rolls before it falls onto the material to be rolled.
The device for this purpose is a roll cooling water drainer.
The present invention combines two devices with completely different functions, the above-mentioned warping prevention device and roll cooling water draining device, into one guide device. Draining devices for roll cooling water have existed for a long time. For example, there is Utility Model No. 55-4083. The draining device prevents the cooling water sprayed onto the roll surface from coming into direct contact with the rolled material, but it does not have the function of correcting warpage. Therefore, even if such a draining device is installed, if upward warpage occurs in the rolled material,
This cannot be corrected automatically. Therefore, after the material to be rolled has completely passed through the rolling mill,
The material to be rolled is transferred to the next process (for example, a subsequent rolling mill,
The material to be rolled is stopped once on the conveying table before reaching the rolling material (shearing machine, pinch roll, etc.), and the tip of the material to be rolled is pressed down with a weight or something similar to correct the warpage, and then the material to be rolled is sent to the next process. I was sending it in. In this way, the rolling material has to be stopped once for maintenance, which is very problematic in terms of safety and work efficiency. In addition, because the conveyance of the material was stopped during straightening, there was a large amount of heat loss due to heat radiation during this time.
There was also a huge waste of energy.

As described above, the conventional method involves problems in terms of safety, operation, and energy saving, and there has been a desire for a new technology that can solve these problems all at once.

(Purpose of the invention) Based on the current state of the art as described above, the present invention was developed by using a roll that scoops up the drainage water from the work roll after cooling the work roll and before it falls onto the material to be rolled. Cooling water drain function and when upward warpage occurs in the rolled material at the rear of the rolling mill,
By devising a guide device that also has an upward warpage correction function that automatically corrects this, we have succeeded in simultaneously satisfying three items that were previously impossible to solve: safety, operability, and energy saving. This is the purpose.

(Structure of the invention) The gist of the invention is that in a steel plate hot rolling mill, the work roll is suspended in a swingable structure above the rear pass line, and its tip is suspended by a moment due to its own weight or an external force. The roll cooling water is always in contact with the work roll to drain the roll cooling water, and at the same time, the lower surface of the drain plate is angled so that it approaches the pass line as it moves away from the work roll. This is a rolled material warping prevention device that has a water draining function.

(Example) The present invention will be explained in detail below using an example device shown in the drawings. First, regarding the drain function of this invention,
This will be explained with reference to FIG. The guide plate 1 in the present invention is suspended by a shaft 6 and is swingable around the shaft 6, and the shaft 6 is structured to be shiftable along the frame 5. In addition, the center of gravity of the guide plate 1 is located behind the vertical line passing through the axis 6, and the moment due to its own center of gravity M ₁ - M ₂ = Gl ₁ However, G
is the center of gravity of the guide plate 1, and _l1 is given by the horizontal distance between G and pin p, but because of this _M1 , its tip is always in contact with the upper roll 4 of the work roll, and the thickness of the material to be rolled is Due to the difference, even if the upper work roll 4 moves up and down, the tip of the guide plate 1 does not come off the upper work roll 4. Therefore, the spray water 9 sprayed onto the work roll cooling water from the work roll cooling water spray header 8 disposed along the roller 7 cools the work roll 4.
Thereafter, it descends along the surface of the work roll 4, but is scooped up by the tip of the guide plate 1 that is always in contact with the work roll 4, and does not fall onto the work roll M. Water is drained below the roller table 11 from both sides.

Next, the warping prevention function of the invention will be explained using FIGS. 2 and 3.

First, in FIG. 2, when the tip of the rolled material M warps upward behind the rolling work rolls 4, the tip of the rolled material M collides with the bottom plate of the guide plate 1, and the rolling mill continues while maintaining contact. Moment _M2 given by the rolled material M to the guide plate 1 as it passes backwards
is M ₂ = F μl ₃ − Fl ₂ where, F is the reaction force exerted by the rolled material M on the guide plate 1 μ is the friction coefficient l between the rolled material M and the guide plate 1 ₂ is the horizontal distance from the contact point to the pin p l ₃ is given by the vertical distance from the contact point to the pin p, but when M ₁ + M ₂ becomes positive, the guide plate 1 tries to move away from the rolling work roll 4;
Finally, it is supported by the stopper 3 with a shock absorber,
Straighten the rolled material M.

Next, when M ₁ +M ₂ becomes negative, the guide plate 1 is supported by the work roll 4 and the pin p to straighten the rolled material M, as shown in FIG.

The main functions of the present invention have been described above, and below, the movement when the work rolls 4 are rearranged will be described.

In FIG. 4, when changing the work rolls, etc., if the guide plate 1 is in contact with the work rolls 4, it may cause trouble. In such a case, the shift cylinder 2 pushes the guide plate 1 toward the rear of the rolling mill. At this time, the cylinder 2 pushes the through shaft 17, and the through shaft 17 pushes the elongated hole 16 made in the guide plate 1. 16 is a long hole, so the through shaft 17
Although the horizontal force from the guide plate 1 is received, the swinging of the guide plate 1 is not restricted. At this time, when the tip of guide plate 1 separates from the roll, the guide plate receives a moment due to its own weight.
It falls over due to M ₁ and appears as shown in Figure 4. At this time, the tip of the guide plate 1 completely enters the shadow of the housing 14 of the rolling mill, so that it does not interfere with the rearrangement of the work rolls 4. After the work rolls have been rearranged and inspected, the work rolls 4 are attracted to the guide plate 1 by the shift cylinder 2 from the state shown in FIG. At this time, the guide plate 1 is moved by the cam plate 15 attached to the inside of the rolling mill housing 14 and the cam roller 13 attached to the tip of the guide plate 1.
is smoothly inserted into the lower part of the upper work roll 4.

The shape of the rear side of the guide plate 1 is determined so that the minimum clearance l ₅ between the guide plate 1 and the pass line in Fig. 4 is larger than the minimum clearance l ₄ during correction in Fig. 2. The structure also allows for the passing of empty pass materials.

(Effect of idea) The present invention exhibits the following excellent effects.

a By devising a warp prevention guide that also has a work roll cooling water drain function, it is now possible to achieve both safety, operability, and energy savings, which were previously considered impossible.

b The present invention makes it possible to prevent operation stoppages due to warpage of rolled material, and increases line capacity.

c. Along with the above effects, there is no longer any need for acquisition intervention related to upward curvature, improving safety.

d By adopting the present invention, it is possible to prevent the deterioration of the heating fuel consumption rate due to the temporary stoppage of the line due to the occurrence of upward warpage.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the draining function of the apparatus according to the embodiment of the present invention, FIGS. 2 and 3 are explanatory diagrams of the warp correction function, and FIG. 4 is an explanatory diagram of the same operation. 1: Guide plate, 2: Guide plate shift cylinder, 3: Stopper with shock absorber, 4: Work roll for rolling, 5: Guide frame, 6: Guide plate support pin shaft, 7: Work roll cooling water header, 8: Work Roll cooling water spray header, 9: Work roll cooling water spray water, 13: Roller for cam, 14: Rolling machine housing, 15: Guide plate for cam, M: Material to be rolled, 16: Long hole in guide plate 1, 17: Through shaft, p: Pin.

Claims (1)

[Scope of utility model registration request] In a hot rolling mill for steel plates, the work roll is suspended in a swingable structure above the pass line on the rear surface of the work roll, and its tip constantly contacts the work roll due to the moment due to its own weight or external force, thereby discharging the roll cooling water. An apparatus for preventing upward warpage of rolled material having a function of draining roll cooling water, characterized in that the lower surface of the drain plate is angled such that it approaches a pass line as it moves away from the work roll at the same time as draining.