JPS6289895A - Energizing roll for surface treatment - Google Patents

Abstract

PURPOSE:To improve the corrosion resistance and durability of an energizing roll in an electrolyte by subjecting the surface of an iron core to plating of Cu, Ni, and Cr to form the energizing roll to be used in the stage of electrolytic cleaning, electroplating, etc. CONSTITUTION:The energizing roll for a steel strip to be used in the stage of subjecting the steel strip to electrolytic cleaning and electroplating by moving the strip while immersing the same in the electrolyte and energizing the strip is constituted by forming a Cu plating 2 to about 1mm thickness on the surface of the iron core 10 of the roll, forming an Ni plating layer 5 to about 0.1-0.2mm thickness thereon and further forming a Cr plating layer 1 to 35-113mum thickness thereon. The surface thereof is finished to a dull surface. The Ni plating layer 5 having excellent corrosion resistance is formed as the substrate for the Cr plating layer 1, by which the electrolyte infilt rating through through-cracks 11a formed by fine cracks 1 in the Cr plating layer 1 is blocked by the Ni plating layer 5 and the corrosion of the Cu plating layer 2 is prevented.

Description

[Detailed Description of the Invention] "Object of the Invention" The present invention relates to the invention of an energized roll for surface treatment, which is used for electrolytic cleaning or electroplating in a surface treatment line for steel strips, etc. The purpose of this invention is to improve the corrosion resistance of a roll for energizing in a liquid in a corrosive atmosphere, and to provide a highly durable energizing roll.

Industrial applications: Electrical roll for electrolytic cleaning or electroplating of strips in surface treatment lines.

Conventional technology steel) An IJ tube is continuously passed through an electrolytic bath, and a current is applied between one pole, such as an anode, provided in the electrolytic bath and the strip to perform surface treatments such as electrolytic cleaning and electroplating. In order to perform this, it has been commonly employed to supply power using a current-carrying roll. By the way, since such a current-carrying roll is installed in a corrosive atmosphere, corrosion resistance must be achieved. In the past, as shown in FIG. is being formed.

Problems to be Solved by the Invention However, even the conventional energized rolls described above do not have sufficient durability, requiring a considerable amount of cost to maintain the processing line, and moreover, the line maintenance is required many times, and the maintenance time is extremely long. This has the disadvantage of hindering production. If the hard chrome plating is thin, it is difficult to obtain a uniform and stable plating layer, and if the plating is too thick, cracks are likely to occur.

Means for Solving the Constituent Problems of the Invention A surface treatment product characterized in that a nickel plating layer is formed on the surface of an iron core roll via a copper plating layer, and a chromium plating layer is formed on the nickel plating layer. Electrifying roll.

The nickel plating layer prevents corrosive treatment liquid from penetrating through minute cracks in the chrome plating layer, and the chromium plating layer is formed using this nickel plating layer as a base, thereby increasing the durability of current-carrying rolls used for plating, etc. improves.

The nickel plating layer protects the copper plating layer and prevents corrosion of the copper plating layer.

EXAMPLE To further explain the present invention as described above, the inventors of the present invention conducted a detailed study on the corrosion state of the conventional energized roll as described above, and found that the ROM plating layer has a thickness of 0, for example. It was confirmed that the chrome-plated laminated structure had a layered structure with a thickness of about .5 to 0.8 μm, and that fine cracks 11 as shown in FIG. 3 were distributed in the thickness direction. However, it is presumed that the plating solution penetrates into the cracks 11& where such fine cracks 11 penetrate the metal chromium layer 1, and the penetrating solution also corrodes the CU layer 2, causing the plating to peel off. It was recognized that

Therefore, in the present invention, as shown in FIG.

Forming the copper plating layer 2 on the surface of the iron core roll 10 itself is the same as the conventional method described above, but the nickel plating layer 5 is formed on the copper plating layer 2, and the nickel plating layer 5 is A chromium plating layer 1 with a thickness of 35 to 113 μ- is formed on top, and a nickel plate with a thickness of O-1 = about 0.2 m is formed on a copper plating layer 2 with a thickness of about 1-1 as a base. A plating layer 5 is formed, and the chromium plating layer 1 is formed using the nickel plating layer 5 soaked in corrosion resistance as a base, so that the above-mentioned micro cracks 11 or 11m in the chromium plating layer IK are treated. This prevents liquid from entering and protects the copper plating layer 2.

To explain a specific manufacturing example of the device according to the present invention, as shown in FIG. It has a dull finish.

Comparing the product of the present invention obtained in this way with a conventional product that does not have a nickel plating layer, the results show that the roll surface is maintained and regenerated (including the copper plating layer, appropriately scraped off and re-plated with each type). (processing for dimensional restoration) at least 4 to 5 months, i.e. 50% of the conventional
It is possible to extend the length of time.

According to the present invention as described in detail, a nickel plating layer is formed between the copper plating layer and the chromium plating layer applied to the iron core roll, thereby increasing the durability of this type of current carrying roll for surface relief. This invention is industrially very effective because it can reduce the number of times of line maintenance and the number of man-hours for line maintenance.

[Brief explanation of drawings]

The drawings show embodiments of the present invention, and FIG. 1 is a side view with the intermediate part omitted showing the general structural relationship of the device according to the present invention, FIG. 2 is an enlarged cross-sectional view of a part thereof, and FIG.
The figure is an enlarged explanatory view of the structure of the chrome plating layer, and FIG. 4 is a partially cutaway side view of the conventional one. However, in these drawings, 1 is a chrome plating layer, 2 is
5 is a copper plating layer, 5 is a nickel plating layer, and 10 is an iron core roll. f4/ En No. 4 I Figure 2 Figure 3

Claims (1)

[Claims] A current-carrying roll for surface treatment, characterized in that a nickel plating layer is formed on the surface of an iron core roll via a copper plating layer, and a chromium plating layer is formed on the nickel plating layer.