JPH09125163A - Pressure pad for supporting float-up of strip - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the unstable floatation state of a strip developed, by which if a heat strain is developed in a nozzle part, the uniformity of gas injected from the nozzle is lost and a static pressure range formed on a pad face become unstable, in a pressure pad for supporting the float-up of the continuously carried metallic strip. SOLUTION: The pad face 1 of the pressure pad P is made of a heat resistant cast steel and this pad face 1 is freely attached/detached to the pressure pad body. Further, plural pad surfaces 1 are divided into plural pieces along a line extended in the strip carrying direction. In this result, it is reduced to develop the heat strain having the permissible limit or higher to the pad faces 1, particularly nozzles 8, 108, 208 and the strip can be stably supported while floating up in a long time. Further, in the case of developing the heat strain, since only divided pieces 2, 3, 4 at the corresponding position can be changed, the change work is facilitated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure pad for levitating and supporting a metal strip continuously conveyed, and more particularly to a pad face opposed to the metal strip.

[0002]

2. Description of the Related Art Conventionally, a pressure pad having a sectional shape shown in FIG. 5 is known. In this pressure pad 20, a box-shaped hollow pressure pad body 21 is formed of heat-resistant steel such as stainless steel, and a high-temperature gas is supplied to an internal space 22 thereof. When the pressure pad 20 is used for annealing an aluminum strip, the temperature of the high-temperature gas supplied to the internal space 22 is 800 ° C.
However, when it is used for annealing a stainless steel strip, the temperature of the high-temperature gas becomes 1000 ° C. or more.
Causes thermal strain. Therefore, when the temperature of the high temperature gas exceeds a predetermined value as in the processing of stainless strip, the pressure pad main body 21 is covered with the heat insulating layer 24 made of, for example, castable except the pad face 23. A water cooling pipe 25 is arranged in the heat insulating layer 24, and the pressure pad body 21 is cooled by the water supplied to the water cooling pipe 25 to prevent the occurrence of thermal strain. On the other hand, the pad face 23 cannot be water-cooled because the nozzles 33 and 34 for ejecting high-temperature gas are formed in a pair in the transport direction of the strip S.

As shown, the pressure pad 20 is disposed below a strip S which is continuously conveyed, and sends the high-temperature gas supplied to the internal space 22 of the pressure pad body 21 through the nozzles 33 and 34. By spraying on the lower surface of the strip S, a static pressure region 36 is formed between the strip S and the pad face 23, and the strip S is stably levitated and supported.

[0004]

By the way, the pressure pad body 21 of the pressure pad 20 has a heat insulating layer 2.
4 and is cooled by the cooling water supplied to the water cooling tube 25, so that heat distortion hardly occurs. However, the pad face 23 having no cooling means is heated by the high-temperature gas and greatly distorted. At this time, the distortion generated in the pad face 23 changes the shape of the nozzles 33 and 34, and the gas ejected through the nozzles The supply pressure or the supply direction changes, and the static pressure region 36 formed on the pad face 23 becomes extremely unstable. As a result, the floating support state of the strip S is not stable, and the strip S swings up and down, left and right, and comes into contact with and damages the pad face 23 and the like.

If the pad face 23 is distorted, it must be replaced with a non-distorted pad face. However, the currently used pad face 23 is a single piece and is heavy. For this reason, the replacement operation was extremely difficult.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the problems. A pressure pad according to the present invention has a pad face formed of heat-resistant cast steel and is divided at least into two in a strip width direction. I have.

[0007]

In this pressure pad, since the pad face is made of heat-resistant cast steel, the occurrence of thermal distortion is smaller than that of heat-resistant steel. Therefore, not only can the static pressure region be stably formed for a long time, but also the frequency of replacing the pad face becomes extremely low. Further, since the pad face is divided, the replacement work is facilitated.

[0008]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows a plan view (a) of a pressure pad according to the present invention and a sectional view (b) of a pad face. Although only the cross section of the pad face is shown in the cross-sectional view (b), this pad face constitutes the upper part of the box-shaped pressure pad as described in the section of the prior art. , And is detachably attached to the pressure pad body.

In FIG. 1, a pad face 1 of a pressure pad P is made of heat-resistant cast steel having less heat distortion than heat-resistant steel, and has four lines I, I ', and II extending in a strip conveying direction indicated by an arrow X. , II ′, five divided pieces, ie, a central divided piece 2, two divided pieces 3, 3 ′ adjacent to both sides of the divided piece 2, and a divided piece 4, which is located outside the divided pieces 3, 3 ′, 4 '. The divided pieces 3 and 3 'and the divided pieces 4 and 4' have the same shape.

FIG. 2 shows a plan view (a), a front view (b), a left side sectional view (c), and a right side view (d) of the outermost split piece 4 of the split pieces. . In these figures, upper nozzle walls 5 and 5 are formed to extend obliquely upward at both ends of the divided piece 4 in the transport direction, and a plate-like face is provided between the upper nozzle walls 5 and 5. A part 6 is provided. At both ends of the face portion 6 in the transport direction, lower nozzle walls 7, 7 extending diagonally downwardly facing the upper nozzle walls 5, 5 are provided, and between the upper nozzle wall 5 and the lower nozzle wall 7. The nozzle 8 is formed. The upper nozzle wall 5 and the lower nozzle wall 7 are connected at a plurality of locations by ribs 9.

On the upper surface of the face portion 6, "rectangular" rectifying walls 10 are provided in parallel at regular intervals. A plurality of cutout grooves 11 are formed in the flow straightening wall 10 at predetermined intervals. In the present embodiment, the rectifying wall 1
Although 0 is provided integrally with the face portion 6, it may be provided detachably or movably so that the position thereof can be changed. The flow regulating walls 10 are formed as a pair in two rows, and between the pairs, a large number of holes 12 penetrating the face portion 6 are formed in a single row, and the gas supplied to the pressure pad P is supplied to the nozzle 8 and the nozzles 8. Straightening walls 10, 1 through holes 12
Injection starts from 0. A plurality of reinforcing walls 13 are integrally formed on the lower surface of the face portion 6 and extend in the transport direction and the width direction of the strip. On the other hand, bolt holes 14 are formed around the divided piece 4 at predetermined intervals.

FIG. 3 shows a plan view (a), a front view (b), a left side sectional view (c), and a right side view (d) of the split piece 3 inside the split piece 4. The divided piece 3 has basically the same configuration as the above-described divided piece 4. Therefore, the same components are denoted by the same reference numerals as those obtained by adding 100, and description thereof is omitted. In addition, in the divided piece 3, the portion overlapping the divided piece 4 is reduced by the thickness of the face portion 6 of the divided piece 4 to form the step portion 115, so that the divided piece 3 and the divided piece 4 are overlapped. However, there is no step on the face. In the divided piece 3, the rectifying wall 110 is
A pair of rectifying walls 11 are formed in a row and
A plurality of holes 112 are formed between 0 and 110.

FIG. 4 is a plan view (a) of the center divided piece 2,
A front view (b), a left side sectional view (c), and a right side view (d) are shown. This divided piece 2 also has the above-mentioned divided piece 4
Has basically the same configuration. Therefore, divided piece 4
The same components as those are denoted by the corresponding reference numerals with 200 added and description thereof is omitted. However, in the center divided piece 2, the rectification walls 210 are formed in two rows each symmetrically,
A plurality of ejection holes 216 are provided in the face portion 206 in these central regions. Further, in the divided piece 2, a step portion 215 is formed by lowering an outer end extending in the strip conveying direction (the direction of the arrow X) by the thickness of the face portion, respectively. 3, 3 'are overlapped.

The pad face 1 having the above configuration is
The nozzles 8, 108, 208 of the divided pieces 2, 3, 3 ', 4, 4' are arranged in a row as shown in FIG. At this time,
On the steps 215, 215 of the center split piece 2, the split pieces 3, 3 'arranged outside thereof are superimposed, and similarly, on the step portions 115, 115 of the split pieces 3, 3', the outer Are overlapped. Also, the bolt holes 14, 114 of the divided pieces 2, 3, 3 ', 4, 4',
A bolt (not shown) is inserted into the pressure pad 214, and the divided pieces 2, 3, 3 ', 4, 4'
And the split pieces 2, 3, 3 '
And the divided pieces 3 and 4, 3 'and 4' are connected to each other.

In the operating state, the high-temperature gas, for example, high-temperature air supplied to the pressure pad P is jetted from a pair of nozzles 8, 108, 208 provided in the conveying direction, and is strip conveyed on the pad face 1 (see FIG. 1). Not shown)
Is sprayed on the underside of the pad to form a pool of hot air, ie a static pressure area, between the pad face 1 and the strip. At the same time, the hot air is supplied to the pair of rectifying walls 10, 110,
Injected from the holes 12, 112, 212 arranged between 210 to form an air curtain, the rectifying walls 10, 11
Together with 0 and 210, the movement of high-temperature air trying to escape from the static pressure region is regulated, so that the static pressure region is stabilized. Therefore, the strip is levitated and supported in a stable state.

In the case where the thermal distortion of the divided pieces 2, 3, 3 ', 4, 4' exceeds the allowable limit, the divided piece having the thermal distortion is replaced with a new divided piece. However, since the pad face 1 according to the present invention is made of heat-resistant cast steel, the heat distortion is smaller than that of the conventional heat-resistant steel, and the frequency of replacement is significantly reduced as compared with the conventional product.

In the above embodiment, the rectifying walls 10, 1
10, 210 are shaped like "C", but may be arched or straight.

[0018]

As described above, according to the present invention, since the pad face is made of heat-resistant cast steel, thermal distortion is less likely to occur than that of the conventional heat-resistant steel. Therefore, the strip can be stably levitated and supported for a long time. In addition, when thermal strain exceeding the allowable limit occurs,
Since only the distorted pieces need to be replaced, the replacement operation is facilitated.

[Brief description of the drawings]

FIG. 1 is a plan view (a) of a pad face of a pressure pad according to the present invention and a cross-sectional view (b) taken along the line BB of the pressure pad shown in the plan view.

FIG. 2 is a plan view (a), a front view (b), a left side sectional view (c), and a right side view (d) of an outermost pressure pad divided piece.

FIG. 3 is a plan view (a), a front view (b), a left side sectional view (c), and a right side view (d) of a second pressure pad divided piece from the outside.

FIG. 4 is a plan view (a), a front view (b), a left side sectional view (c), and a right side view (d) of a central pressure pad divided piece.

FIG. 5 is a sectional view of a conventional pressure pad.

[Explanation of reference symbols] P ... Pressure pad, 2, 3, 3 ', 4, 4' ... Divided piece, 6, 106, 206 ... Face portion, 8, 108, 2
08 ... Nozzle.

Claims (1)

[Claims] 1. A strip floating support pressure pad having a pad face detachably provided to a main body of a pressure pad arranged to face a continuously transported strip, wherein the pad face is formed of heat-resistant cast steel. And a pressure pad for supporting the floating of the strip, wherein the pressure pad is divided into at least two in the strip width direction.