JPH0437892Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial field of application> The invention is a continuous annealing furnace for metal strips,
The present invention relates to a strip floating support device that supports a metal strip in a non-contact manner during threading.

<Prior art> Conventionally, in the case of a horizontal continuous annealing furnace in which a strip such as a steel plate is passed horizontally and annealed continuously, the strip is supported by support rolls provided in the annealing furnace. I was boarding. However, since the strip heated to a high temperature is brought into contact with the support roll, surface defects such as pick-up defects and thermal deformation are likely to occur in the strip.

<Problems to be solved by the invention> When considering the above-mentioned conventional strip support conditions in detail, it is found that steel strips of various dimensions (plate thickness, plate width) are produced in a continuous annealing furnace. However, the dimensions of the flotation support device for the strip are usually designed for the widest steel strip. However, when trying to support narrow steel strips with such a strip flotation support device, there was the inconvenience that the same amount of gas was required to levitate the steel strip even if the width was wide. .

The cause of this is that gas is wasted in order to levitate the steel strip by the difference between the width of the steel strip to be levitated and the length of the fluid jet port (the part where the steel strip is not above the fluid jet port). This is because

The present invention aims to solve the above-mentioned disadvantages of the conventional strip flotation support device and provide a strip flotation support device having a fluid spout having a length matching the width of the strip.

<Means for Solving the Problems> In order to achieve the above-mentioned object, the strip flotation support device of the present invention forms a pressure-receiving surface facing the lower surface of the strip on the lower side of the strip to be transported. It has a main body, and has slit-shaped openings extending in the width direction of the strip at the front and rear ends of the pressure receiving surface along the traveling direction of the strip, and allows fluid to flow obliquely upward into the center of the pressure receiving surface. In a strip flotation support device equipped with a set of fluid jet ports that eject fluid to generate static pressure between the strip plate and the pressure-receiving surface, the length of the fluid jet ports can be adjusted according to the width of the strip plate. The invention is characterized in that it is equipped with a device for adjusting the temperature.

<Function> Therefore, since the width of the strip to be buoyantly supported matches the length of the fluid jet port for buoyantly supporting the strip, it can be adjusted freely even with narrow strips. It can be floated efficiently.

<Example> Next, a typical example of the present invention will be described. The strip flotation support device of this embodiment will be described as a strip flotation support device used from the latter half of the heating zone, which has the highest temperature, to the soaking zone and the latter half of the cooling zone, in the continuous annealing furnace.

1 to 3 show the schematic structure of the strip flotation support device of the embodiment, FIG. 1 is a plan view of the main part of the strip flotation support device when installed in an annealing furnace, and FIG. 2 is a A cross-sectional view taken along line A-A in Figure 1, and Figure 3 is a cross-sectional view taken along line B-- in Figure 1.
It is a sectional view of B.

The strip flotation support device 1 of the embodiment is disposed in the furnace wall 10 of an annealing furnace, and in the figure, 3 indicates the slit-shaped fluid jet port, and 4 indicates the length (width direction) of the slit-shaped fluid jet port. A slide stopper 5 is a driving device for moving the slide stopper 4 forward and backward for adjustment, and 6 is a steel strip plate.

The strip flotation support device 1 has a slit-shaped fluid spout 3 extending in the width direction of the steel strip 6 on the lower side of the steel strip 6 on the side opposite to the lower surface of the steel strip 6. This slit-shaped nozzle 3 extends in the width direction of the steel strip 6, and is provided at the upper and lower downstream ends of the strip flotation support device 1, respectively.
These pairs of slit-shaped nozzles 3 are formed so that the ejected fluid 2 (usually gas) is ejected obliquely upward relative to the lower surface of the steel strip plate 6 so as to face each other.

Inside the strip flotation support device 1, there are shown in FIG.
As shown in Fig. 3, a chamber 7 is provided which is filled with a mixed gas such as nitrogen and hydrogen.
The upper part of the steel plate 6 forms a smooth pressure receiving surface 8, and the pressure receiving surface 8 receives the static pressure generated by the gas 2 ejected into the space 9 below the steel strip plate 6.

The steel strip 6 is levitated and supported by this static pressure, and is transported by traveling above the strip flotation support device 1.

In the strip flotation support device 1 of this embodiment, a sliding plug 4 penetrating the furnace wall 10 is provided in the slit-shaped fluid jet port 3, and as described above, it can be moved forward and backward according to the width of the steel strip 6. The structure is such that the length of the slit-shaped fluid jet port can be adjusted by moving it. As shown in FIGS. 2 and 3, the slit-like fluid outlet 3 is formed in the shape of a wedge with a convex tip, and a sliding stopper 4 having a circular or polygonal cross section is inserted into the wedge-shaped outlet. It has a structure that seals gas by the contact surface 4a with the wedge-shaped inner surface. Furthermore, a drive device 5 for sliding the sliding plug 4 back and forth is provided at the end of the furnace wall 10 opposite to the slit-shaped fluid spout 3.

By adjusting the opening length of the slit-shaped fluid jet port 3 and the length of the steel strip plate 6 to be approximately the same,
All the fluid (gas) ejected from the slit-shaped fluid ejection port 3 flows into the space 9 between the steel strip plate 6 and the pressure receiving surface 8.
is spent on work that generates static pressure.

Figure 4 compares the strip floating support device of the present invention and a conventional device with respect to the gas flow rate and levitation height that should be ejected when steel strips of the same thickness but different widths are levitated. When the length of the slit-shaped fluid jet port is long, the same levitation height A can be obtained in both the conventional strip levitation support device and the strip levitation support device according to the present invention. Then, the same gas flow rate B is required, but the width is narrower (the steel strip width is 1/
In the case of 2), in order to obtain the same levitation height, using the device of the present invention, the gas flow rate can be approximately 1/2 that of the conventional strip levitation support device.

In addition, in the strip flotation support device of this embodiment, since the driving device 5 for the sliding plug 4 that adjusts the length of the slit-shaped fluid spout is provided outside the furnace wall 10, the influence of the temperature inside the furnace There is no risk of damage or malfunction due to thermal deformation.

<Effects of the invention> As is clear from the above explanation, the strip flotation support device according to the present invention has the following characteristics: ○B. When the thickness of the strips to be conveyed is the same, the amount of fluid ejected per unit width is approximately equal. Therefore, the production cost of narrow strip plates can be reduced, and the difference in production cost due to the difference in width can be eliminated.

○B Since the length of the slit-shaped fluid spout of the strip flotation support device can be continuously changed by using a sliding stopper, strips of any width can be efficiently levitated.

○C Furthermore, by providing a device for driving the sliding plug outside the furnace wall, the device can be operated without being affected by heat, chemicals, etc.

[Brief explanation of the drawing]

FIG. 1 is a plan view of essential parts of a strip floating support device according to an embodiment of the present invention, FIG. 2 is a sectional view taken along line AA in FIG. 1, and FIG. 3 is a sectional view taken along line BB in FIG. 1. FIG. 4 is a characteristic diagram showing a comparison of gas flow rate (Q/W) per unit plate width versus levitation height between the strip floating support device of the present invention and the conventional strip floating support device. In the figure, 1...Strip plate flotation support device, 2...Gas ejected from the slit-shaped fluid jet port, 3...Slit-shaped fluid jet port, 4...Sliding type plug, 5...Sliding type plug driving device, 6... Steel strip plate, 7... Chamber, 8... Pressure receiving surface, 9... Space between the lower surface of the steel strip plate and the pressure receiving surface.

Claims (1)

[Scope of utility model registration request] A main body forming a pressure-receiving surface facing the lower surface of the strip is provided on the lower side of the strip that travels and is transferred, and a main body that forms a pressure-receiving surface that faces the lower surface of the strip is provided, and a plate width of the strip is provided at the front and rear ends of the pressure-receiving surface along the traveling and transferring direction of the strip. A set of fluid ejection ports are provided at the center of the pressure receiving surface, each having a slit-like opening extending in the direction, and ejecting fluid obliquely upward to generate static pressure of the fluid between the strip plate and the pressure receiving surface. 1. A strip flotation support device, characterized in that the strip flotation support device is provided with a device for freely adjusting the length of the fluid jet port according to the width of the strip.