JPS5983784A - Multi-purpose continuous acid-pickling apparatus - Google Patents

Abstract

PURPOSE:To enable to selectively change a liquid acid in response to the kind of a sheet material to be treated during its passage, by providing tanks for reserving various kinds of liquid acids in a continuous annealing-acid pickling line in a manner such that an optional liquid acid can be freely sent into an acid pickling tank in the acid pickling line. CONSTITUTION:In the continuous annealing-acid pickling line to acid pickle a predescaled steel strip 2 in acid pickling tanks 10, 11 and a high-pressure spray washing machine 12, a tank 21 for hydrochloric acid, a tank 23 for sulfuric acid, a tank 25 for nitric and fluoric acids and a tank 27 for nitric acid are provided in a tank 9 for reserving liquid acids, separately connected to a means 29 for supplying a new liquid acid and installed in a manner such that a liquid acid can be properly supplied to the acid pickling tank 10 or 11 through each means 22, 24, 26, 28 for charging or discharging a liquid acid. Hence, the liquid acids can be properly conjointly used in response to the kind of a sheet material to be treated during its passage, and various kinds of steel strips can be acid pickled in one line.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multi-purpose continuous pickling device capable of annealing, pickling or pickling copper strips of stainless steel, ordinary steel or all other steel materials in one line. .

Copper strips such as stainless steel and stainless steel are made into products through repeated rolling and annealing, but the maceration scale that is generated during this process impairs the beauty of the appearance and impairs corrosion resistance, so it must be completely removed. .

Conventionally, stainless steel strips are descaled by preliminary descaling using shot blasting, light pressure trawls, bending rolls, or molten alkali salt or neutral salt electrolysis incorporated in the continuous annealing and pickling line (hereinafter abbreviated as AP line). processing and
This is mainly carried out by pickling with nitric-fluoric acid.

On the other hand, descaling of ordinary steel etc. is usually carried out on a continuous pickling line, which is separate from the AP line for stainless steel, mainly for hot-rolled steel strips, and methods include short blasting, light reduction rolls and bending rolls. This is carried out by combining a mechanical preliminary descaling treatment such as by et al. and pickling treatment with sulfuric acid or hydrochloric acid.

Mechanical descaling as a pretreatment for ordinary steel is almost similar to that for stainless steel, and it is not impossible to share the same equipment, but for pickling, if the pickling liquid is for ordinary steel, Unlike stainless steel, sulfuric acid or hydrochloric acid is mainly used, so although stainless steel and ordinary steel as mentioned above require pickling, they each need to be treated in separate lines. there were. For this reason, each pickling treatment line is susceptible to the operating rate due to fluctuations in the supply-demand balance for stainless steel, ordinary steel, etc., and especially when production volume decreases, costs are forced to increase due to a decrease in line operating rate. There was a disadvantage.

In addition, the present inventors used 6-fluoric acid for pickling stainless steel rust (6-fluoric acid), which generates harmful NOx gas during pickling and is expensive, so as an alternative pickling method, We developed and proposed methods for treatment resistance, (1) hydrochloric acid treatment followed by nitric-fluoric acid treatment, and (5) sulfuric acid treatment followed by nitric acid treatment.

The present invention can perform all the conventionally known pickling methods for ordinary steel, high carbon steel, etc., including the pickling method proposed in section 1F for stainless steel, as well as the conventionally known nitrofluoric acid method. The purpose is to provide an AP line that can respond to fluctuations.

The gist of the present invention to achieve the above object is to provide an AP line that can continuously feed copper strips and perform annealing and pickling, which is equipped with a plurality of types of acid solution storage tanks. This multi-purpose continuous pickling device is characterized in that any pickling solution can be freely fed into the pickling tank of the line, and the acid solution can be freely changed and selected depending on the type of material to be threaded. With the present invention, all iron chain materials such as stainless steel and ordinary steel can be annealed and processed on the same line.
It becomes possible to perform pickling or pickling, and various improved pickling treatments for stainless steel proposed by the inventors of the invention can be carried out using the same device.

No. 11K shows a system diagram of the AP line according to the embodiment of the present invention. In Fig. 1, the steel strip 2 discharged from the steel strip dispensing machine 1 is threaded in the direction of the arrow, passed through the entrance looper 3, sent to the heating furnace 4, subjected to necessary heat treatment, and cooled in the cooling zone 5. After that, a preliminary descaling process is carried out in the scale breaker 6, the doplast electrolytic tank 8, and then the pickling solution, which is preset according to the type of material to be threaded and the purpose of processing, is transferred to the acid solution storage tank device. Pickling tank 1 supplied from 9 and prepared
0 and 11 for pickling, a high-pressure water spray washer 12 removes lubricants and acid content stuck to the surface of the copper strip, and after a final spray wash f'11, it is dried in a dryer 13. The copper strip winder 15 passes through the exit looper 14 and winds up the copper strip.

FIG. 2 shows a system diagram of one embodiment of the acid liquid storage tank device. The acid liquid storage tank device 9 includes a tank 21 for hydrochloric acid, a tank 23 for sulfuric acid, a tank 25 for nitrogen fluoride, and a tank 2 for 11+M.
7 and the dairy washing liquid supply/discharge devices 22, 24, 26, 28 attached to each of them and the new #armpit supply device 2 of each.
It consists of 9.

Pickling tanks 10 and 11 are used depending on the type of material to be threaded and the purpose of processing.
, . . . to carry out pickling by introducing acid solutions as shown in the following (a) to (i), respectively.

(a) Tsuchishima acid - nitric acid (b) Hydrochloric acid - nitric-fluoric acid (C) Salt-resistant - nitric-fluoric acid - nitric acid (d) Sulfuric acid - nitric-fluoric acid (e) Sulfuric acid - nitric-fluoric acid - nitric acid (f) Sulfuric acid - Nitric acid (g) Nitric hydrofluoric acid (h) Hydrochloric acid (1) Sulfuric acid The above (a) to (g) are suitable for threading stainless steel, and for threading alloy steel other than stainless steel, ordinary steel, etc. In this case, the pickling liquids shown in (h) to (i) above are placed in a pickling tank to carry out pickling.

If the number of types of acid to be fed into the pickling tank may be small depending on the type of material to be threaded or the processing purpose, the same acid may be fed into a plurality of pickling tanks.

Note that the present invention does not limit the type of acid used or the number of pickling tanks. That is, in the case of an AP line in which there are many types of acids to be used, but the types of acids to be pickled at the same time are limited to a few, for example, in the case of the dedicated lines of (g) to (i) above, or in the case of the above (C), AP that does not perform the process in (e)
In the case of a line, pickling equipment with one or two pickling tanks is not excluded.

A heating furnace and a scale breaker for preliminary descaling treatment in a series of treatment steps in the AP line of the present invention.
, Shoku], blasting, and neutral salt electrolytic cell equipment can be used appropriately depending on the type of material to be passed through and the purpose of processing, and there is no restriction on the provision of other descaling equipment.

With the present invention, it is now possible to anneal and pickle or pickle copper strips of stainless steel, back-through steel or all other ferrous materials in one line. Therefore, the annealing and pickling treatment can be carried out by any of the many wash-resistant treatment methods developed by the present inventors depending on the type of material to be threaded and the processing purpose. I can do it.

[Brief explanation of the drawing]

Fig. 1 is a system diagram of an AP line according to an embodiment of the present invention;
The figure is a system diagram of the wash-resistant device. ■...Copper band dispensing machine, 2...Copper band, 3...Enter side looper, ↓...Heating furnace, 5...Cooling zone, 6...
Scale Breaker-17...Shot Blast, 8.
... Neutral salt type IV tank, 9 ... Acid liquid storage tank device, 1
0.11...washing resistant tank, 12...high pressure water spray l/- washer, 13...dryer, 14...outlet root cooler,
15... Copper band winding machine patent applicant Kawasaki Steel Co., Ltd. agent Patent attorney Yoshio Kosugi

Claims (1)

[Claims] 1. The IJP annealing and pickling line, which can continuously send out copper strips and perform annealing and pickling, is equipped with multiple types of acid solution storage tanks, and any pickling solution can be stored in the pickling tank of the pickling line. 4! Multi-purpose continuous pickling equipment with f characteristics.