Electroplating Process Specification - Overview

Roller plating is a method of gravure substrate processing, and it is also an important means to increase the service life of the gravure plate. However, due to the special nature of the electroplating process theory and practice, each plate-making company takes its own experience as the main issue, and the problem arises: “there is no way to deal with problems”. As a result, a variety of control methods have emerged. More scientific and instructive process specifications have caused problems in production, causing many versions of the rollers to be repaired.

In the past, the author made a record of three months in four plate-making companies with a certain scale (about 3,000 cylinders per month). The types of electroplating rework problems were analyzed. The monthly average repair volume statistics are shown in Table 1. .

From Table 1, it can be seen that the amount of electroplating rework accounts for about 3% of the production volume of the plate cylinder, and the plate-making company with better management is about 2%. There are many reasons for returning repairs, which involve six factors: people, machines, materials, fluids, laws, and rings. Therefore, in the production process, we must pay attention to returning repair as an important task, strengthen basic management, establish standardization documents for each procedure, combine ISO9002 quality system certification, implement standardized and data-based operations, and strictly require employees to strictly follow the rules. The data manipulation ensures the stability and improvement of plating quality.

This article is a summary of some of the plate-making companies in the implementation of standardized management of electroplating process, trying to find out a set of more practical control methods, in order to effectively and steadily improve the quality of electroplating. Published here, only for the reference of colleagues, if there is something wrong, please correct me.

The precision of gold processing must be high. To achieve positive concentricity of the roller, the dynamic balance does not pulsate, and the finish is good. In actual production, due to the concentricity of some plate rollers, the left and right shades are not correct, and they are not on one line, resulting in network change, uneven color, and overprinting in printing. Therefore, many plate-making companies are making efforts to grasp the accuracy of gold processing and standardize the quality standards of gold processing. The main measures are as follows

The quality of a standardized gold processing

(1) Welding is a very critical step. At this stage, the next good copper tube is assembled with the processed boring cap. It is necessary to ensure that the two are welded at an angle of 90°. No disconnection, porosity, or welding is allowed. Partial problems arise.

(2) Copper pipes must have no cracks, no blisters, or blind holes. If you find any of the above problems, apply a copper wire with a 2mm diameter and then apply it again.

(3) The precision error specification of Jingong is: the error in the axial dimension shall not exceed 0.03mm; in the diameter error, the grinding plate shall be controlled within 0.02mm, the grinding plate shall be controlled within 0.05mm, and the taper of the plate roller (ellipse Degree) error shall not exceed 0.02mm.

(4) The misalignment of the taper holes at both ends of the platen roller cannot exceed 0.05mm, and some companies have a specification of 0.02mm, which is difficult to achieve in production. The main reason for the concentricity is that the center frame is not erected during operation. In this case, rough repair holes, rough grinding (finishing), and then fine-refining holes and grinding methods are effective. On the slope, the concentricity can basically reach 100%. Second, due to equipment problems, the vertex is not on a line. Therefore, we must carefully and carefully operate and improve the equipment.

(5) The chamfer must be sleek and transitional and polished with iron sandpaper.

(6) Drum finish to reach 8.

(7) The phenomenon of vertical runout cannot occur in the dynamic balance. The error should not exceed 50 to 100 g. Otherwise, the overprint accuracy of the printing will be affected. In particular, large deviations may occur during high-speed printing.

(8) Due to the current unstable quality of billet processed by gold, the routine inspection system should be standardized. The method is: The billet is loaded on the proofer and proofed with black ink. If the billet has obvious regular lines (such as twill, mosaic, horizontal stripes, etc.), it will affect the copper plating. When the copper crystal is crystallized, it will crystallize along different directions of the grain, resulting in non-uniform bonding force of the copper plating layer. It is best to use a billet with an irregular pattern and a smooth surface, but it is not necessarily the brighter the better.

(9) In the production, when the old version of the old material was used, it was troublesome due to the unevenness of its plate wall and poor measurement due to stuffing and welding. The experience of some master chefs is to choose a heavy version of the roller, because the heavy version of the roller plate thickness, ease of processing.

After gold processing, the gravure cylinder needs to be plated with nickel and copper to enable electronic engraving. Nickel plating mainly enables the copper layer to bond firmly with the roller core. This is an important part and should be taken seriously.

(to be continued)