Textured Electroplating Roller

In the late 1990s, the world began to develop a large number of textured chrome-plated rollers and successfully applied them to new production lines. At the same time, textured chrome-plated rollers were used to replace rubber and non-woven rollers in the process of rebuilding old lines. Roller. To a certain extent, whether a process line uses textured chrome-plated rollers and how much is used can basically reflect the overall equipment level of the line.

Chrome-plating rollers and textured chrome-plating rollers are mainly continuous production lines such as continuous retreat, hot-dip galvanizing, and silicon-silicon steel. The main features are high unit speed, high production efficiency, and good product quality. A large number of surface textured chrome-plating rollers are used in such production lines. , such as tension rollers, turning rollers, looper rollers, rectifying rollers, pinch rollers, etc.

Production requirements for textured chrome plating:

1. After the roller body is completed, the roller surface is ground;

2. Generally, the textured chrome-plated roller cannot be subjected to any machining after electroplating, but only by grinding, polishing, peak cutting and other treatments. Therefore, the accuracy of the entire roller must be guaranteed by grinding. After grinding, the dimensional accuracy and geometric tolerances (roundness, cylindricity, runout, etc.) must meet and exceed the technical requirements of the drawings.

3. Surface roughness: Another main purpose of grinding is to ensure the accuracy and smoothness of the roller surface, and to meet the requirements of roughening and electroplating of the roller surface. It is generally required that Ra≤0.8µm should be reached after grinding, and a contact roughness meter should be used for measurement.

4. Grinding vibration pattern: by visual inspection and chalk inspection, there should be no continuous and obvious regular grinding vibration pattern. If obvious vibration lines can be seen by visual inspection (or side light observation), it is regarded as unqualified; if continuous and regular vibration lines are found in chalk inspection, it can also be judged as unqualified. The defect is more clearly visible after texturing plating.

5. Grinding roll marks: Visual inspection and chalk inspection are not allowed to have obvious circumferential or spiral roll marks.

6. Grinding Short Scratches (Fly Feet):

For the grinding process, it is impossible to completely eliminate short scratches. The main reasons are the level of the grinding machine, the quality of the grinding wheel, the grinding process and the filtration of the emulsion. But it should be strictly controlled within a certain range and to a certain extent. 1) It is not allowed to have obvious dense short scratches; 2) It is not allowed to have obvious short scratches with touch; 3) The length of short scratches generally cannot exceed 15mm.

7. Basic acceptance criteria for roll blank quality before electroplating:

7-1 Surface Defects

1) No pore defects with a diameter exceeding Φ0.5mm are allowed; no cracks, slag inclusions, heavy skin, rust, looseness and other plate or welding defects are allowed;

2) It is not allowed to have closed pores with diameter less than Φ0.5mm;

3) For open pores with diameter less than Φ0.5mm:

No more than 3 are allowed within 100×100mm, and dense distribution is not allowed;

No more than 3 are allowed on the 100mm length, and dense distribution is not allowed;

The whole roll is not allowed to have more than 10 defects.

4) The roll surface is not allowed to have scratches, bumps, abrasions and other accidental damages caused by improper transportation and hoisting protection;

7. The roller surface is automatically sandblasted and textured;

8. Adopt vertical rotary chrome plating;

9. Textured chrome-plated finished roller;

Appearance quality of coating:

1. The appearance of the coating is smooth, flat and comfortable, showing silver-gray bright metallic luster (if it is dark gray or has no obvious metallic luster, it means that the coating quality is poor, and the hardness and bonding strength of the coating are not ideal);

2) The color of the coating itself is uniform and there is no obvious color difference (it has nothing to do with the color difference of welds, soft tapes, repair defects, etc.);

3) The textured state of the surface of the whole roller is uniform, and there is no obvious difference in reflection due to uneven roughness;

4) No obvious chrome burrs are allowed after the roller surface is plated (due to the tip discharge effect during electroplating, even if it is properly controlled, tiny burrs will be generated, but they can be removed by post-plating peak cutting);

5) Pinhole defects with a diameter exceeding Φ0.5mm are not allowed;

For pinhole defects with diameter Φ0.3-Φ0.5mm: not more than 5

For pinhole defects with diameter less than Φ0.3mm: not more than 10

The whole roll is not allowed to have more than 10 defects.

No more than 3 are allowed within 100*100mm, and dense distribution is not allowed;

The hardness of the chrome layer can reach HV900 or more, so the general use temperature of the hard chrome layer can reach 550°, and the chrome layer has good corrosion resistance. There are still a large number of manufacturers using chrome-plated rollers (such as Baosteel 2030 continuous withdrawal line) in the medium and low temperature area on the continuous withdrawal production line, and the use effect is good, and the overall service life is at the level of 5 to 10 years.

The surface roughness can be more according to the actual production line requirements of the user, and the roughness of the roll surface at different positions can be different. Generally, the roughness of the textured chrome-plated roll is Ra=1.6-4.5 range.

The maximum diameter can be D2200, which is widely used in Baosteel Zhanjiang, Wuhan Iron and Steel, Shougang, Anben Iron and Steel, Taiyuan Iron and Steel, Hegang, Shanshan Iron and Steel, Maanshan Iron and Steel, Guangzhou Iron and Steel, Guangdong Pohang, Guangzhou JFE, etc.