JPS62164834A - Floating type strip passing device - Google Patents

Abstract

PURPOSE:To apply approximately uniform low tension to a metallic belt-like body over the entire length thereof and to smoothly pass said body by floating and supporting the metallic belt-like body to be passed by a gas floating and supporting device and further generating the shifting magnetic field in the pass direction by linear shifting magnetic field type induction motors. CONSTITUTION:The strip 1 to be passed in an arrow direction in a continuous annealing line, etc., is floated and supported by the gaseous pressure of the gas ejected from the gas floating and supporting device consisting of floaters 4 each of which has a slit 9 and is connected with a gas duct 5. The linear shifting magnetic field type induction motors consisting of a pair of linear motors 10A, 10B are further disposed symmetrically with the pass direction of the strip 1 as a center below the strip 1 to generate the shifting magnetic field in the pass direction of the strip 1. The tension on the strip 1 from the outside is thereby decreased, by which the generation of the deformation, etc., thereof is prevented and the quality of the product is improved.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is applicable to continuous annealing lines, continuous galvanizing lines,
This invention relates to a floating plate threading device used in lines that handle metal strips, such as stainless steel annealing lines and colored iron plate coating lines.

<Prior Art> First, a continuous annealing furnace for cold fffl rolled steel sheets will be described as an example of a line for passing a metal strip (hereinafter referred to as a strip).

The strip fed out from the payoff reel and passed through the cleaning tank and looper is supplied to a continuous annealing furnace shown in FIG. 7, 2ζ. In the furnace shown in the same figure, rolls 2 are arranged in the upper and lower parts, and the strip 1 is heated and cooled as necessary while running up and down on the rolls 2rIR, and is heated and cooled to a predetermined level at room temperature. Material properties such as high tensile strength and good deep drawability should be added. More specifically, the inside of the strip 1 is filled with reducing HN gas to prevent surface oxidation, and the strip 1 is normally heated at 650°C to 650°C.
Added by radiant tube 3 up to ssO'cf1 degree
It is heated in 4 zones, then soaked for several tens of seconds, and then heated at 400℃.
It undergoes a process of being rapidly cooled to about 100°C, subjected to an overaging treatment at about 400°C for about 2 minutes, and finally rapidly cooled to room temperature.

By the way, in the vicinity of the exit of the heating zone of such a continuous annealing furnace, the stosop 1 with a height of 1 comes into contact with the slightly cold roll 2, and the strip 1 is deformed and rolled due to uneven cooling in the width direction of the strip 1. Problems include the occurrence of defects in the strip 1 due to the adhesion of carposis in the oil and contact with the uneven roll surface.

Due to the above-mentioned problem, in order to prevent the high-temperature strip from coming into contact with the rolls and to run the strip horizontally, a floater (gas flotation support device) 4 is installed in the furnace as shown in FIG. A method is adopted in which the strips are arranged below the lip 1 or on both upper and lower sides to make the strip 1 float and run horizontally. In Figure 8, the metal strip 1 runs from left to right in the figure;
Radiant tubes installed on the upper and lower surfaces; 4 is a floater that supports the weight of the strip by ejecting HN gas to generate pressure between the strip; 5 is a gas flotation support device; 5 is a gas flotation support device for supporting the strip; Supply gas duct, 6
is the furnace wall. The floater 4 has a cross-sectional structure shown in FIG. 9, and the floater 4, which communicates with the gas duct 5, has a slit 9 at the HN gas ejection port, so that the HN gas ejected from the hole 9 is directed in the flow direction. is suddenly changed, and pressure is generated between the strip 1 and the strip 1 due to the change in momentum.

<Problems to be solved by the invention> In order to eliminate the adverse effects caused by the heating temperature of the high temperature strip 1,
The structure shown in FIG. 8 is such that the floaters 4 are arranged horizontally. The strip 1 to be passed through the continuous annealing furnace may have a total length of several hundred meters, and is routed in a meandering manner many times vertically or horizontally, so it is difficult to pass the strip 1 outside the furnace. It requires a lot of tension to pull it out. For this reason, a larger tension acts on the strip 1 as it approaches the exit side of the furnace, and sometimes an excessive tension is applied to the strip 1, causing creep phenomena and one-sided elongation, especially in the strip 1 that exists in a high temperature range. Wrinkles, etc. were observed, leading to deterioration of product quality.

In view of the above-mentioned problems, the present invention is a floating strip threading method that applies a low tension that is almost uniform over the entire length between the entry and exit sides of the strip during threading in the furnace, and allows smooth strip threading. The purpose is to provide equipment.

Means for Solving the Problems> The floating type strip threading device of the present invention includes a gas levitation support device for ejecting gas and floating and supporting the metal strip to be threaded by the gas pressure; Metal strip (sl-IJ)
The motor is equipped with a linear moving magnetic field type induction motor (hereinafter referred to as a linear motor) that generates a moving magnetic field in the threading direction of the lubricant.
It is characterized by:

Effect〉 If the strip is threaded along the regular pass line,
The strip is placed at key points and receives a driving force acting in the direction of strip passing due to the moving magnetic field of the near motor, and the presence of this driving force relieves the tension acting from outside the furnace and pass through smoothly.

Embodiment An embodiment of the present invention will be described with reference to FIGS. 1 to 5. Incidentally, the same parts as the conventional ones are given the same reference numerals.

As shown in FIG. 1, the floating plate threading device includes a floater 4 having a slit 9 formed therein and communicating with a gas duct 5.
a pair of linearly moving magnetic field type induction motors (linear motors) disposed below the strip 1 and symmetrically with respect to the threading direction of the strip 1 supported in levitation by the floater 4; It consists of 10A and IOB.

As shown in FIGS. 2 and 3, both linear motors IOA and IOB include a yoke 12 made of a magnetic metal material having several teeth 12a, and an AC power source (not shown) that is wound around the teeth 12a. A plurality of coils 11 connected to
The linear motors IOA and IOB each generate a moving magnetic field of equal magnitude in the sheet passing direction.

The driving principles of these linear motors IOA and IOB are not particularly different from those known in the past, and there are various driving methods depending on the number of current phases and micropoles (number of N and S poles). It is not limited to a limited method. Here, the most typical two-pole three-phase system will be explained. In FIGS. 3 and 4, A, B, and C in the drawings indicate coils 11 corresponding to three phases, respectively, and A', B'
, C' are wound around the yoke 12 in the opposite direction to the coils 111 of A, B, and C, respectively. These A
.

Current IA whose phase is shifted by %π in the coils 11 of B, C, A', B', and C' rBI Io# IA' l
When I@'P■o' flows, a magnetic field proportional to the current is generated in the toothed portion 12a around which each coil 11 is wound.

IA, IA' = I. Embroidery θ [,, [,' = Io Yu (θ+100π) Io, Io'
=IOam (θ-iπ) The graph shown by the solid line in Figure 4 represents the X-direction intensity component of the magnetic field generated above the yoke 12 (in the Y-direction), and is for the case where the current phase θ=O. It is. The shape of this magnetic field is the linear motor IOA,
Since the number of poles of IOB is two, one N pole and one S pole are generated, so it is almost in the form of a sine wave.
When the above current phase θ changes from O to 2π in a certain period,
In accordance with this change, the sine wave of the magnetic field also moves in the direction in which the phase advances (X direction in FIG. 4). The graph shown by the dotted line in FIG. 4 is for the case where the current phase θ=%π.

The magnetic field generated above the yoke 12 and moving linearly exerts the following force on the conductor disposed above the yoke 12. In other words, when a moving magnetic field crosses a conductor, a magnetic current is generated inside the conductor according to Maxwell's law of induced magnetic field, and the interaction between this island current and the magnetic field causes a so-called Lorentz current to flow in the same direction as the moving magnetic field. Power is generated.

The linear motors IOA and IOB are disposed symmetrically with respect to the center RM (passing direction, see FIG. 5) of the strip 1, which is a conductor, and with a gap below the strip 1. Linear motor 10A.

The strength of the moving magnetic fields generated in each of the magnetic strips 10B is set to be equal, and the moving direction thereof is set to follow the direction in which the strip 1 passes, as shown by the arrows in FIG. Therefore, the fifth
As shown in the figure, center line M is linear motor IOA, IOB
Strip 1, which is located at the regular threading position in the center between the strips, is equipped with a near motor IQA.

Forces fA and f caused by the moving magnetic field 10B act in the direction of travel of the strip 1 and have the same magnitude.

In this way, when the strip 1 is running at the normal threading position (pass line), the forces fA and fB acting on the strip j and lip 1 are multiplied with each other, and the strip 1 moves in the threading direction. Let me. These driving forces fA and fB need to be adjusted according to the thickness of the strip 1, the running speed, etc., but this can be easily done by adjusting the magnitude and frequency of the current applied to the linear motor, the size of the linear motor, etc.

Note that the number of pairs of linear motors to be provided can be determined as appropriate, and depending on the plate width, it may be one. Furthermore, the installation position of the linear motor can be freely set not only below the strip 1 but also above, or above and below. Further, in the above embodiment, the linear motor is arranged at an intermediate position of the floater 4 as shown in FIG. Floater 4 as shown in
It can also be incorporated into and distributed.

<Effects of the Invention> According to the floating type threading device of the present invention, the tension acting on the strip threaded while being floated and supported by the gas levitation support device is dispersed by the linear motor at multiple parts during threading. This prevents excessive tension from being applied over the entire length of the strip present in the furnace. Therefore, when the present invention is applied to a continuous annealing furnace, the overaging zone can be shortened without any problem, and high quality products can be produced.

[Brief explanation of drawings]

1 to 5 relate to one embodiment of the present invention, in which FIG. 1 is a perspective view of a floating plate threading device, FIG. 2 is a plan view of a beam near motor, and FIG. 3 is an I-- (2) A cross-sectional view taken in the direction of arrows, FIG. 4 is an explanatory diagram of the operation of the beam near motor, and FIG. 5 is a plan view of the beam near motor portion of the floating plate threading device. FIG. 6 is a sectional view of a floater with a built-in beam near motor. FIG. 7 is a schematic diagram of a continuous annealing furnace, FIG. 8 is a sectional view of an overaging zone, and FIG. 9 is a sectional view of a floater. In the drawing, 1 is the strip, 4 is the floater, 10A is the IOB beam near motor, and M is the center line of the strip. Figure 2 Figure 4 Figure 6 Figure 7■ Figure 8

Claims (1)

[Claims] A gas levitation support device for ejecting gas to levitate and support a metal strip to be threaded by the gas pressure, and a linear moving magnetic field type induction motor for generating a magnetic field for moving the metal strip in the threading direction. A floating sheet threading device characterized by: