JP2916522B2 - Hot-dip galvanizing method for steel wire rods - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a steel wire rod which is continuously passed through a flux line, and subsequently immersed in a molten zinc-aluminum alloy bath, and finely adjusts the amount of adhesion. The present invention relates to a method for coating a molten zinc-aluminum alloy on a steel wire material.

[0002]

2. Description of the Related Art As a means for imparting corrosion resistance to a steel material, a two-step hot-dip galvanizing method in which a flux is treated and then dipped in a hot-dip zinc bath at another stage is generally used. The molten zinc-aluminum alloy plating method with excellent corrosion resistance is adopted, and this flux treatment contains ammonium chloride and fluoride together with zinc chloride, stannous chloride and potassium chloride, or Various flux compositions to which various metal salts such as aluminum chloride, cupric chloride, silver chloride and molten lead are added have been developed and proposed.

[0003] However, when the steel wire is coated with a molten zinc-aluminum alloy, a long steel wire is continuously passed at a relatively high speed and immersed in the molten zinc-aluminum alloy bath. In addition, it is necessary to adjust the adhered adhesion amount by squeezing to make the adhered adhesion amount highly accurate. In addition, the flux treatment and the plating alloy bath become extremely short because of relatively high-speed wiring, and it is necessary to continuously plating for a long time. However, the immediate effect and performance of the flux treatment do not meet the above requirements. The ammonium chlorides and fluorides are corrosive, generate harmful gases and white smoke, and affect the composition ratio and characteristics of the plating alloy bath with the addition of various metal salts. If the one-step plating method is followed, where the molten zinc-aluminum alloy is coated after the flux treatment, the flux residue accumulates and accumulates in the molten zinc-aluminum alloy bath, and together with the working environment, the aluminum concentration and the fluidity, etc. of the plated alloy bath are reduced. In the conventional flux composition for iron and steel materials, such as being damaged, the adhesion to the steel wire material becomes unstable, and unmeasured and unevenness of the surface of the metal, unevenness of the gloss and the like easily occur. This is not applicable when steel wire is attached one step.

[0004] Therefore, a two-step plating method is employed in which a steel wire is flux-treated to apply molten zinc, and then, in a separate step, the molten zinc-aluminum alloy is applied using the molten zinc as a base. However, the cost is increased due to complicated processes and large facilities.

[0005]

When a conventional flux composition for a steel material as described above is used in the coating of a steel wire material with a molten zinc-aluminum alloy, a high-speed wire for a long steel wire material is used. Cannot meet the demands of high accuracy and high precision plating, and cannot obtain a product with satisfactory precision.Therefore, the two-step plating method is used as described above. Therefore, there is a problem in developing a method for coating a molten zinc-aluminum alloy that enables a single-step coating of a steel wire rod with a molten zinc-aluminum alloy over a long period of time.

[0006] The present invention has been developed in view of the above-mentioned situation, and an object thereof is to provide a solution of a flux composition having a component ratio corresponding to high-speed wire passing of a steel wire, In addition, by finely adjusting the adhesion amount of the plating alloy at the narrowed section defined on one side of the molten zinc-aluminum alloy bath and passing through the wire, etc., the flux performance is improved and the reliability is improved, and the composition ratio of the plating alloy bath The fluxing performance and reliability by minimizing the effect on fluidity, fluidity, etc., and making it possible to achieve a stable and stable molten zinc-aluminum alloy coating over a long period of time by one-step plating. An object of the present invention is to provide a method for plating a molten zinc-aluminum alloy on the steel wire as described above.

[0007]

SUMMARY OF THE INVENTION According to the present invention, a steel wire is continuously passed through, and based on 70 to 80% by weight of zinc chloride, 10 to 20% by weight of stannous chloride and an alkali metal or alkaline earth. It contains 5 to 20% by weight of a chloride of a class of metals and glycerin as an organic foaming material.
After immersing the steel wire in a solution of the flux composition to which 5% by weight was added and performing flux treatment, the steel wire was subsequently immersed in a molten zinc-aluminum alloy bath to obtain a molten zinc-aluminum alloy bath. The method is characterized by a single-step hot-dip zinc-aluminum alloy plating method for steel wire rods in which the wire is passed through by finely adjusting the amount of adhesion of the alloy to the steel wire rod at the narrowed section formed on one side. The composition ratio was determined to include 10 to 20% by weight of stannous chloride, 10 to 20% by weight of stannous chloride and 5 to 20% by weight of alkali metal or alkaline earth metal chloride in the flux composition. As a result, in the flux treatment and continuous zinc-aluminum alloy plating of continuous wires of steel wire, the flux performance and the shin-condality are improved in accordance with the shortening of the immersion time, etc. The effect on the composition ratio and fluidity of the alloy bath is reduced, the separability of flux components at the plating alloy attachment part is increased, and the stable and stable zinc-aluminum alloy plating for a long time is achieved by a one-step plating method. The flux processing performance, alloy plating performance, and reliability are improved by enabling high accuracy.

[0008]

[Action] Zinc chloride is greatly increased (70-80% by weight) and used as a base. Its high dissolving action enhances the dissolving function of metal oxides and the like on the surface of the base material of steel wire and has strong reducing power. It contains an appropriate amount of active and low melting point stannous chloride (10 to 20% by weight) and an appropriate amount of alkali metal or alkaline earth metal chloride (5 to 20% by weight) which is more active than aluminum. By adding 1.0 to 1.5% by weight of glycerin as an organic foam material, the flux component ratio and the concentration, temperature, treatment corresponding to the requirements such as high-speed wire passing and high-precision plating of the steel wire material. Time and drying conditions are adjusted, and the influence on the composition ratio and fluidity of the molten zinc-aluminum plating alloy bath is reduced, and the aluminum concentration ratio and bath fluidity of the plating alloy bath over a long period of time. Is cheap Allowed, molten zinc steel linear material - Aluminum alloy plated superior flux performance corresponding to, to obtain a reliable and enable this stage plated,
In addition, the narrowing part of the plating alloy bath is partitioned to eliminate the influence of the adhesion of the flux component and the accumulation of the residue in the adhesion part of the plating alloy, and stabilize the adhesion amount of the plating alloy for a long time. In addition to the flux processing performance, the plating performance and reliability have been improved.

[0009]

1 and 2 show an embodiment of the present invention. In the figure, a is a steel wire (for example, a hard steel wire), 8 is a drawn portion formed by dividing one of the molten zinc-aluminum plating alloy bath 9 and 10 is a molten zinc-aluminum of the steel wire a. Flux composition suitable for alloy plating, 11
Is a molten zinc-aluminum alloy bath.

In the embodiment shown in the drawings, a steel wire a is continuously passed through, and based on 70 to 80% by weight of zinc chloride, 10 to 20% by weight of stannous chloride and an alkali metal or alkaline earth metal. Contains chlorinated chloride of 5 to 20% by weight and glycerin as an organic foaming material in an amount of 1.0 to 1.5% by weight.
In the solution of the added flux composition 10, the steel wire material a
Immersion and flux treatment, and then the steel wire a
Is immersed in a molten zinc-aluminum alloy bath 11 and finely adjusted the amount of the adhered alloy of the steel wire material a in a narrowed section 8 formed in one section 9 of the molten zinc-aluminum alloy bath. It is a molten zinc-aluminum alloy plating method characterized by one-step plating.

More specifically, the above flux composition 10 is based on zinc chloride which is increased to 70-80% by weight, and stannous chloride is added to an appropriate amount of 10-20% by weight, alkali metal or alkaline earth. An appropriate amount of chloride KCl or the like of a class of metals is contained in an appropriate amount of 5 to 20% by weight. That is,
Compared with the flux composition used in conventional steel materials, zinc chloride, stannous chloride and alkali metal or alkaline earth metal chloride KCl, etc. are used in a relatively high ratio of 5 to 20 in an appropriate amount, respectively. Glycerin as an organic foaming material and 1.0 to
1.5% by weight is added to the components to greatly enhance the function of each component, and for the application of a molten zinc-aluminum alloy that meets the requirements for high-speed wiring and high-precision plating of steel wire a. It has a flux composition. In addition, the use of an ammonia-based or fluorine-based component or various metal salts that inhibit the plating function makes it possible to apply the molten zinc-aluminum alloy in one step. Another feature is that a narrowed portion 8 formed by partitioning 9 is provided on one side of the plating alloy bath to eliminate the influence of flux residue and accumulation thereof on the adhesion of the plating alloy. The chlorides include potassium K, lithium Li, sodium Na,
Alkali metal such as cesium Cs or calcium C
a, one or more of alkaline earth metals such as strontium Sr are applied. This flux composition 1
0 is used as a solution as described below.

The method of the present invention for coating a steel wire rod with a molten zinc-aluminum alloy is performed in a continuous plating line as shown in FIG. A remarkably long steel wire a that is continuously fed at high speed from the swift 1
(Hard steel wire) 2.0 mmφ is degreasing 2 (removing dirt such as lubricating oil or burning in a molten lead furnace at 400 to 450 ° C.), pickling 3
After a treatment (for example, HCl having a concentration of 10 to 20% and HCl at a temperature of 50 ° C.) and washing with water 4, it is immersed in a solution of the flux composition 10 in the flux tank 5 to carry out flux treatment.

The flux composition 10 is made into a 10 to 40% solution by an appropriate means, and the steel wire a is passed through the wire at a relatively high speed so that a 70% solution is added to the flux composition 10 solution.
After immersion at 2 ° C. or more for 2 seconds and flux treatment, followed by drying 6 and then 440 ° C. containing 4.6% of aluminum
Is immersed in a molten zinc-aluminum alloy bath 11 by a sinker roll 7, taken out of the plating alloy bath 11, and reduced by a narrowing section 8 defined in a section 9 to an appropriate amount of the deposited zinc-aluminum alloy. Fine-tuned.

The plating alloy (Zn, Al) is affected by the speed of the wire and the like, and is accurately adhered to the plating layer having a desired thickness by adjusting the aperture 8 and the like. For example, the linear drawing speed of the steel wire a is 20 to 40 m / min, and the coating adhesion amount is 160.
Is set to ~450g / ^{m 2} level. The continuous plating line shown in FIG.
It has a mechanism for one-step aluminum alloy plating.

[0015]

[Table 1]

As shown in Table 1, the long samples 1 to 12 were plated for one hour while changing the composition ratio of the flux composition 10, and the plating was evaluated by appearance.

In the samples shown in Table 2, the weight ratio of zinc chloride, which is a representative example of the flux composition 10 of the present invention, is 75%, the weight ratio of stannous chloride is 15%, and the weight ratio of potassium chloride is 10%. %, Glycerin was added at a weight ratio of 0 to 2.0%, and as shown in Table 2, long samples 21 to 26 were continuously attached for 10 hours or more and evaluated.

[Table 2]

As is clear from the evaluation in Table 1, samples 4 to
No adhesion was found in 6, 8 to 10, and a coated film having good surface smoothness was obtained with high accuracy. That is, based on zinc chloride at 70 to 80% by weight, stannous chloride 1
By using a flux composition containing 0 to 20% by weight and 5 to 20% by weight of an alkali metal or alkaline earth metal chloride, it is possible to apply a molten zinc-aluminum alloy by one-step plating on steel wire a. Good and stable product can be obtained. The flux composition shown in Table 1 is based on an increased amount of zinc chloride (70 to 80% by weight), and its high melting action enhances the function of dissolving metal oxides on the surface of the base material of the steel wire rod. Contains an appropriate amount of stannous chloride (10 to 20% by weight) having a reducing power and an active and low melting point, and an appropriate amount of chloride (5 to 20% by weight) of an alkali metal or alkaline earth metal which is more active than aluminum. Accordingly, it is possible to obtain the flux performance, the plating performance, and the reliability corresponding to the requirements of the plating wire speed and the high precision plating of the steel wire material. Further, as is apparent from Table 2, when glycerin is further added in a weight ratio of 1.0 to 1.5% by weight, the aluminum concentration ratio and bath fluidity of the plating alloy bath are stabilized for a long time. It has been confirmed that one-step plating can be performed with high precision. As described above, 1.0 to 1.5% by weight of glycerin as an organic foam material
When added, the flux composition adhering to the steel wire and mixed into the molten zinc-aluminum alloy bath 11 is separated and floated at once with the bubbles of the organic foam material, and the adhesion of the flux component and the accumulation of the residue are suitable. The effects and effects described above have been confirmed, for example, the components of the plating alloy bath and the plating adhesion amount are stabilized for a longer time.

As described above, by adding 1.0 to 1.5% by weight of glycerin as an organic foaming material of glycerin, the flux composition adhering to the steel wire can be rapidly converted to an organic material in a plating alloy bath. The flux component 1 which was separated and floated at a stretch together with the foam material, and floated as shown in FIG.
0a indicates that the partition 9 provided in the plating alloy bath prevents the inflow to the narrowing portion 8 and the flux component 10 in the narrowing portion 8
The accumulation of “a” is effectively eliminated, and the adhered adhesion amount is stabilized for a long time.

[0020]

The present invention has the above-described configuration,
An increased amount (70-80% by weight) of zinc chloride having an excellent dissolving action is used as a base, and stannous chloride having a strong reducing power and a low melting point is added to an appropriate amount (10-20% by weight), compared to aluminum. Using a flux composition containing an appropriate amount of active alkali metal or alkaline earth metal chloride (5 to 20% by weight) and 1.0 to 1.5% by weight of glycerin as an organic foaming material, By flux treatment of the wire material, the flux component and concentration, temperature, treatment time, and drying conditions are adjusted to meet the requirements of wire speed and high-precision plating of the steel wire material, and the plating is applied. Eliminates components that affect the composition ratio and fluidity of the metal bath, stabilizes the aluminum concentration ratio and bath fluidity of the alloy bath over a long period of time, and makes the molten zinc-aluminum As enabling plated, fluxing performance, to increase the reliability, subsequently molten zinc -
By immersing in an aluminum plating alloy bath and squeezing the one part in the alloy bath, the influence of flux components and pools on the adhesion of the plating alloy is eliminated, and the amount of the adhesion adhesion is reduced for a long time. Flux treatment performance as well as flux zinc-aluminum deposition performance and reliability have been remarkably improved. In addition, there are effects such as simplification of the process and equipment and significant cost savings.

[Brief description of the drawings]

FIG. 1 shows a flux composition diagram (A) used in the plating method of the present invention and a mechanism diagram (B) showing a step of plating the molten zinc-aluminum alloy.

[Explanation of symbols]

 a Steel wire (hard steel wire) 8 Narrowed part 9 Partition 10 Flux composition 11 Molten zinc-aluminum alloy bath

Claims (1)

(57) [Claims] 1. A steel wire rod is continuously passed through, and based on 70 to 80% by weight of zinc chloride, 10 to 20% by weight of stannous chloride and 5 to 20 of an alkali metal or alkaline earth metal chloride. The steel wire is immersed in a flux composition solution containing 1.0% to 1.5% by weight of glycerin as an organic foaming material and subjected to flux treatment, and then the steel wire is melted. Immerse in a zinc-aluminum alloy bath, and finely adjust the amount of the deposited alloy on the steel wire in the narrowed section formed in one section of the molten zinc-aluminum alloy bath to reduce the one-step plating that passes through the wire. A method of plating a molten zinc-aluminum alloy.