Talk about: Some views on improving the production capacity of barrel plating line

01

Foreword

In barrel plating production, it is always hoped that the plating time is as short as possible. Trying to reduce the influence of the mixing cycle of parts is one of the ways to achieve this goal.

Factors such as driving cycle time and process development also affect the increase in production capacity.

These aspects are explained separately below.

02

Mixed cycle

The mixing cycle is the time required for the parts to be turned in and out of the pile of parts in the drum during barrel plating.

It can be produced, one is because the parts are piled up, and the other is because the parts keep rolling.

The mixing cycle of parts is related to the shape, size, speed, load and other factors of the drum.

1. Rotation speed

Improving the rotation speed of the drum is undoubtedly beneficial to shorten the mixing cycle of the parts.

This is because after the rotation speed of the drum increases, the turning force of the drum to the parts is strengthened, so that the parts have more chances to appear on the surface layer. For example, in order to improve the consistency of the overall parts, the method of increasing the rotation speed of the drum is often adopted in the production.

Practice has proved that this method is effective.

Improving the rotation speed of the drum can shorten the mixing period of the parts, but the rotation speed of the drum is limited.

If the drum speed is too high, the grinding effect between parts may be too strong, and the shortening of the electroplating time caused by the shortening of the mixing cycle will be offset.

The principle of selecting the drum speed is: the higher the drum speed, the better without other influences.

In addition, the shape of the part is also an important factor that affects the speed of the drum.

For example, barrel-plated sheet parts often use a higher speed than the conventional drum. This is because sheet parts are easy to stick to each other and cause coating quality problems. Increasing the rotation speed of the drum can reduce the chance of sticking to each other.

For example, the rotating speed of the conventional roller galvanized drum is 5r/rain, while the rotating speed of the gasket roller galvanizing is usually 6-10r/rain depending on the size of the drum.

Under the premise of ensuring that the surface of the parts is not damaged or is slightly damaged, a high roller speed can be used to shorten the mixing cycle of the parts as much as possible.

The rotation speed of the drum is generally different according to the hardness and process characteristics of the coated metal.

In addition, factors such as the size of the roller, the surface properties and shape of the parts, the performance and roughness of the coating, and the hole diameter of the roller will also affect the speed of the roller.

Therefore, the selection of the drum speed in production should be changed according to the specific conditions, rather than set in stone.

Otherwise, it will adversely affect the production efficiency and product quality of barrel plating.

2. Loading capacity

The larger the load of the drum, the longer the mixing cycle of the parts during barrel plating.

Under normal circumstances, the drum loading capacity of common parts is 1/4-2/5 of the drum volume. Less than 1/4, the loading capacity of the roller is too small, not only the production efficiency is low, but also because there are too few parts, it may not be in normal contact with the cathode conductive head.

More than 2/5, the loading capacity of the drum is too large. On the one hand, the mixing cycle of the parts is longer, and the production efficiency may not be improved; on the other hand, the relative decrease in the amount of solution in the drum will cause the mass concentration of metal ions to drop too much. Fast, adversely affect the stability of the plating solution.

The drum loading capacity is in the range of 1/4～z/5, and the optimal value is about 1/3.

In production, we often encounter such a situation: when the entire electroplating process is about to be completed, the remaining parts are sometimes not divided into two drums, so they are installed in one drum for electroplating , The loading volume exceeds the standard, the result is that the thickness and quality of the plating layer are not as good as before in the same plating time, so the plating time has to be extended, and the quality of the final product cannot achieve satisfactory results.

03

Running cycle time

The shorter the driving cycle time, the greater the electroplating capacity.

However, if the electroplating time of the product needs to be delayed, shortening the tact time will not increase the production capacity. On the contrary, it will lead to other conditions that are not conducive to the quality of the product.

If the delay causes the pickling time of a certain drum in the pickling tank to be too long, or to stay in the washing tank for too long before electroplating, etc.

04

Process development

After determining the driving cycle time and the total electroplating station, the longest electroplating time without delay is determined. When formulating the process book, in order to increase the production capacity, the electroplating time of the product should be controlled within the maximum electroplating time.

If the electroplating time exceeds the maximum electroplating time, a delay will be required, which will affect the production capacity and may have other adverse effects; if the electroplating time is shorter than the maximum electroplating time, it will be necessary to empty the electroplating tank, which will also Reduce electroplating production capacity.

Take the current zinc rolling line as an example, the cycle time is 5 minutes, the maximum number of stations is 19, and the longest electroplating time is 95 minutes. If the loading capacity of product A is 80kg and the electroplating time is 80min, only 16 stations are used at this time, and 3 stations are vacant. In order to increase production capacity, the loading capacity of product A can be increased to 90kg.

At this time, all the stations are used, the loading capacity increases without increasing the tact time, and the production capacity is increased.