JPS62139832A - Floating supporting device for changing over direction of traveling steel strip - Google Patents

Abstract

PURPOSE:To control a steel strip to an optimum floating height in any position in the peripheral direction by providing pressure pads before a direction change, in a direction change section and after the direction change and forming these pads in such a manner that the respective pressures can be adjusted. CONSTITUTION:The pressure pads PQ1, PQ2, PQ3 which support the steel strip S are provided after the change of the direction of the steel strip fro the direction A to the direction A', in the direction change section and before the direction change, respectively. Pressure chambers Pc1, Pc2, Pc3 are formed in the respective pads. Gases are supplied through gas supply ports G1, G2, G3 to the chambers Pc1, Pc2, Pc3 and the gases are injected to the steel strip S from a pair of nozzles N1, N2, N3 so that the steel strip is floated from respective pressure receiving surfaces Pp1, Pp2, Pp3. The flow rates of the gases supplied to th chambers Pc1, Pc2, Pc3 are made controllable individually so that the floating height of the steel strip S is made the same in distance from any of the surfaces Pp1, Pp2, Pp3. The generation of contact flaws on the steel strip S is thereby prevented and the running cost is reduced.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a floating support device for changing the direction of a running steel plate in a continuous steel plate annealing furnace, a steel plate continuous plating furnace, a steel plate continuous coating furnace, etc. It can also be applied to drying lines for paper manufacturing, printing machines, and paper coaters.

[Conventional technology]

(1) The conventional device shown in Figs. 3 and 4 is a
rnal of the engineering ron & 5t
eeI In5titude, May1963, P2O
3, the fluid levitation support device 1 comprises an arc portion 2, an air volume 3, and has a pressure chamber 4 inside.

The arc portion 2 is provided with a slit-shaped nozzle 5 extending along the circumference as shown in FIG. 3 and diagonally inward as shown in FIG.

The steel strip 6 is wound around the arc portion 2, the drive pinch roll 7, and the tension adjustment roll 8.

The steel strip 6 is supported by the pressure of the fluid ejected from the nozzle 5 at the arcuate portion 2 in accordance with the principle of a hovercraft.

In the fluid levitation support device 1 shown in FIGS. 3 and 4, the distance between the arc portion 2 and the steel strip 6 of the fluid levitation support device 1 is
If the pressure is the same over the entire circumference of the fluid levitation support device, the fluid pressure will be uniformly generated in the arcuate portion 2 of the fluid levitation support device, as shown by the broken line in FIG.

(2) Next, Japanese Patent Publication No. 44-11451 shows the use of such a hovercraft type nozzle instead of a 180° turn roll, but although the pressure pad itself is divided into four parts, The inside of the pressure chamber is electrically connected to all nozzles. Therefore, it is not possible to control the pressure or flow rate for each nozzle.

[Problem that the invention seeks to solve]

(1) In the apparatus shown in FIGS. 3 and 4, the pressure distribution of the fluid ejected from the nozzle 5 is as shown by the broken line in FIG. 5, but the tension of the steel strip 6 acts on the fluid flotation support device 1. As shown by the solid line in Figure 5, the force is applied at the top (90
Since the distribution is such that the maximum is at the lateral part (0°, 180°) and the minimum is at the side part (0°, 180°), the floating height when the steel strip 6 is supported by the fluid levitation support device l is: The top (90
The distribution is such that the minimum value is at the side part (0°, 180°) and the maximum is at the side part (0°, 180°).

Therefore, there is a possibility that the @ band 6 comes into contact with the top of the device 1, and in order to prevent this, it is necessary for K to increase the fluid pressure on the pressure receiving surface. Inevitably, the flow rate of gas required for levitation must be increased, which increases running costs.

Furthermore, if the floating height of the supporting device is uneven, such that the floating height of the 01lI plane is high and the top is low, there is a problem that the steel strip will be in an unstable floating state.

(2) In the device described in Publication No. 44-11451, it is not possible to control the pressure or flow rate for each nozzle, so attempting to float the top requires an excessive overall pressure or gas flow rate; Further, there is a problem that the height of the side portion becomes unnecessarily high, making threading unstable.

Note that JP-A-52-39509 also mentions lining up pressure pads as a method of applying tension, but the pressure of each pressure pad is either controlled by a common pressure chamber or pressure pads of completely different systems are used. Since there are so many of them placed in parallel, I can't imagine there being any ingenuity in the pressure mod. Therefore, the present invention is also
The problem is similar to that described for 4-11451.

[Means for solving problems]

As mentioned in the prior art section, the practical problems of the fluid floating support device are in preventing contact at the top (90°) and in stably threading the plate. Therefore, the pressure ξrad is 3 in the direction of the plate direction change.
By dividing it into two parts, one for the sides and one for the top, and providing independent pressure chambers for each, the pressure and flow rate of the gas necessary for levitation can be controlled, thereby achieving the optimal levitation height at any position in the circumferential direction. Set the

[Effect]

Contact between the steel strip and the fluid buoyant support device can be avoided by increasing the fluid pressure at the top or turn section where the force acting on the multifluid buoyant support device due to the 5MMo2 tension is greatest.

〔Example〕

FIG. 1 shows the case where the running direction of the @ belt is vertical, and FIG. 2 shows the case where the running direction of the @ band is horizontal. Three pressure pads PQ in both Figures 1 and 2. 1. Pl, 12. PQ3 is installed, each Brera Shavara) PQI, PQ2゜PQ3
There are pressure chambers PCI + ”C2rPc inside, respectively.
3 is formed. Each pressure chamber Pcl, Pc2. Pc3 each have a pair of nozzles Nx, N2 . Na and gas supply ports Gl, G2. G3, and the pressure receiving surfaces Ppl, Pp2.
Pp3 and pressure chambers Pcl, Pc2. Pc3 and pressure pocket PI, P2. It is separated from P3.

Moreover, the pressure chambers Pcl, Pc2. Pc3 is wall W1. W2. W3
Pressure is maintained at . PI, P2. There is a steel strip S on the outside of P3. Arrows A and A' indicate the running direction of the steel strip S.

In the case of this embodiment, pressure pads PQI, PQ2゜P
Q 3C+pressure chamber Pct, Pc2. By individually controlling the flow rate of gas supplied to Pc3, pressure pockets) Pi, P2. The pressure generated at P3 can also be adjusted arbitrarily. Therefore, in the case of the running direction of the line shown in FIG. 1, a large pressure is generated at the portion P2 corresponding to the top (9o0) in FIG. 5, and the side portion Pl is generated.

It is possible to generate a low pressure on P3, and the height at which it is floated can be set at any pressure receiving surface Pp1. Pp2. The same distance can be set from pp3.

In the case of Fig. 2, the tension is 1; the pressure in the P2 area where L contacts is applied is high, then the pressure is high in the Pl area where the weight of the steel strip S acts, and the pressure is the lowest in the P3 area. Each pressure chamber Pc1. If gas is supplied to Pc2 and Pc3, the floating height of the steel strip will be approximately the same in all parts. In addition, pressure pads PPl, PP2, and P
Even if there is some gap between P2 and PP3, if the steel strip is thick, the steel strip will not break because its rigidity is large.

Therefore, in the embodiments shown in FIGS. 1 and 2, a stable levitation state can be obtained because the levitation height will not be higher than necessary, and the power required for levitation can be minimized.

〔Effect of the invention〕

(1) Since the required minimum flying height can be obtained overall, the flow rate of gas required for floating is also smaller than in the past, reducing running costs.

(2) As the floating height is lowered on average, the stability of the steel strip is increased, and the steel strip is free from contact scratches and its quality is improved.

(3) Compact structure reduces equipment costs.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an embodiment of the floating support device for changing the direction of a traveling steel strip according to the present invention in a vertical arrangement, and FIG. 2 is a schematic diagram showing an embodiment of the same horizontal arrangement. Fig. 3 is a perspective view showing an outline of the conventional device, Fig. 4 is a sectional view taken along line A-A in Fig. 3,
FIG. 5 is a diagram showing the balance between fluid pressure and steel strip tension in the arc portion of the conventional device. S... Steel strip, A, 8'... Running direction of steel strip, PQl
. PO2, PO3...Pressure pad, PI, P2.
P3...pressure pocket, Ppl, Pp2. pp3...
・Pressure receiving surface, PCI, PC! 2. PO2...pressure chamber, N
l, N2. N3...nozzle, Gl, G2. G3...
Gas supply pipe sub-agents: 4 patent attorneys, 2 non-authorities, Figure 1, Figure 2, Figure 3, Fan 4, Figure 5, 90゛

Claims (1)

[Claims] In a heat treatment line that changes the direction of a running steel strip, there is a pressure pad for supporting the steel strip before and after the direction change, and a part of the direction change section between the pressure pads has a convex pressure receiving surface. A pressure pad having a curvature is provided, and each pressure pad is provided with an independent pressure chamber and a gas pressure supply source through a common supply pipe that controls the pressure of each pressure chamber with an independent/or damper or the like. A floating support device for changing the direction of a running steel strip.