JPS5952959B2 - Immersion type continuous pickling equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pickling apparatus for continuously pickling rolled strips (hereinafter referred to as strips), and particularly to a continuous immersion pickling apparatus.

Conventionally, in this type of pickling equipment, as shown in Figure 4, the transfer strip is dipped under its own weight into the acid solution stored in the pickling tank, and the oxidized scale on the surface of the list strip is removed by the chemical reaction of the acid solution. It is being removed.

Although this pickling equipment heats the acid solution to accelerate the reaction rate and shorten the pickling time, there is a layer of acid solution on the surface of the immersed strip that moves along with the strip. A so-called boundary layer is formed, which makes it difficult to obtain a pickling rate (pickling effect) that matches the strip conveyance speed. The residence time in the liquid is ensured to achieve the desired pickling rate.

(See FIGS. 4a and 4b) This has resulted in the disadvantage that the pickling equipment becomes long and very expensive. Furthermore, in the pickling equipment, the open surface area of the acid solution stored in the tank is large, and the acid solution is heated and maintained at a relatively high temperature, so that a large amount of acid evaporates from the liquid surface. There were many drawbacks such as increased consumption and difficulty in controlling the concentration of the acid solution. The present invention has been made in order to eliminate the above-mentioned drawbacks, and the immersion strip passes between an agitator protruding from the lower surface of the liquid level shielding plate and an agitator installed opposite the agitator. In this way, the boundary layer generated between the strip and the acid solution is destroyed, which improves the pickling speed, and the evaporation surface is greatly reduced, allowing pickling operations under favorable conditions. The purpose of this invention is to provide a continuous pickling device.

Hereinafter, the embodiment will be described with reference to the drawings. In the drawing, 1 is a pickling tank, and 2 is an acid solution stored in the pickling tank 1.

3 shows the strip to be pickled.

4a and 4b are strip guide wheel devices installed at both ends of the pickling tank 1, and part of the outer periphery of the guide wheels 4a' and 4b' of both guide ring devices is located in the acid solution, and both guide wheels 4a', 4
The structure is such that the strip 3' guided by b' moves approximately horizontally in the acid solution.

5 is a strip 3' between both guide wheels 4a' and 4b'
The stirring protrusions 5 are arranged close to the upper surface of the pickling tank 1, and the protrusions 5 protrude from the lower surface of a liquid level shielding plate 6 placed in the pickling tank 1 in a staggered arrangement.

Stirring projections 7 are arranged close to the lower surface of the strip 3'', and are arranged in a staggered manner on the tank interior stationary plate 8.

Reference numeral 9 denotes a nozzle pipe provided in the middle of the liquid level shielding plate 6 and the tank internal stationary plate 8. In the illustrated device, the acid liquid is jetted from the nozzle pipe 9 toward the strip 3'', and the acid liquid near the stirring protrusion flows. (agitation) is being promoted.

Note that the fluid ejected from the nozzle pipe 9 may be steam. The present invention is configured as described above.

Next, the movement path of the strip and the pickling action will be described.

Strip 3 is the pickling tank] entry side strip guide ring 4a''
Then, both strip guide wheels 4a are introduced into the acid solution 2.
After passing between the stirring protrusions 5 and 7 formed by dipping between the pickling tank 1 and the pickling tank 1, the pickling tank 1 is guided out of the tank by the outlet guide wheel device 4b. The oxidized scale on the surface of the strip 3 is gradually peeled off and removed by the chemical action of the acid solution while moving in the acid solution.
When passing between the stirring protrusions 5 and 7, the gap between the strip 3'' and the tips of the stirring protrusions 5 and 7 is equal to both guide rings 4a''.
, 4b'', the acid solution covering the surface of the strip is kept at a constant small gap by the guiding action of the stirring protrusions 5, 7.
The acid liquid fluid ejected from the nozzle pipe 9 provides good agitation.

For this reason, the boundary layer that tends to form between the strip surface and the acid solution (the layer of acid solution that moves alongside the strip as the strip moves through the acid solution) is destroyed and diffused, so that the strip 3 '' is always in contact with fresh acid solution to effectively remove scale.The open surface of the acid solution stored in the pickling tank is connected to the liquid level shielding plate 6 and both guide wheels 4a'' and 4b''.
The amount of evaporation is extremely small even when the acid solution temperature is maintained at a high temperature. The number and position of the stirring protrusions 5 and 7 disposed close to the upper and lower surfaces of the strip can be freely set by means of the liquid level shielding plate 6 and the tank interior placement plate 8.

Furthermore, in the present invention, fluid is ejected toward the immersion strip 3'' from the nozzle pipe 9 disposed in the stirring protrusion installation plate, and together with the stirring action of the staggered agitation protrusions 5 and 7, the boundary layer is The diffusion effect can be further improved.As described above, according to the present invention, the strip can be pickled effectively under favorable conditions, making it possible to shorten the length of the pickling tank and perform pickling operations with high productivity. There is a big effect.

Brief explanation of the drawings Fig. 1 is a front sectional view of the immersion type continuous pickling device according to the present invention;
2 is a side sectional view taken along line 11 in FIG. 1, FIG. 3 is an enlarged perspective view of section A in FIG. 1, and FIGS. 4A and 4B are explanatory diagrams showing a conventional example.

1... Pickling tank, 3, 3''... Strip, 4a'', 4b''... Strip guide wheel (strip guide device), 5... Stirring protrusion (stirring body), 6... Liquid level shielding plate, 7... Stirring protrusion (stirring body), 8... In-tank stationary plate.

Claims (1)

[Claims] 1. A strip guiding device for moving the strip in a substantially horizontal state along the length of the pickling tank and a staggered agitation body disposed facing the upper and lower surfaces of the immersed strip are provided in the treatment solution, and the immersed strip is The upper agitation body is attached to the liquid level shielding plate, and the lower agitation body is attached to the tank stationary plate, and the middle part of the liquid level shielding plate and the tank internal stationary plate is provided with fluid directed toward the immersion strip. An immersion type continuous pickling device characterized by being equipped with a nozzle pipe that spouts out.