Detailed introduction





How to control the alloy screw?

Color difference isalloy screwThere are many factors that affect the color difference, including resin, masterbatch, masterbatch and the same material mixing, injection molding process, injection molding machine and so on. So how to control the color difference of alloy screw products? This problem has been paid attention to by most industries. Let's discuss it together next!




In the actual production process, we generally control the color difference from the following five aspects. Specific methods are as follows:

1. Eliminate the influence of injection molding machine and mold elements:

Need to choose the main injection product capacity of the appropriate injection molding machine. Ifalloy screwThere are problems such as material dead angle, so replace the equipment. If it is the gating system, exhaust slot and other reasons caused by the color difference. The mold can be processed by repairing the corresponding parts of the mold. It is necessary to deal with the problems of injection molding machines and molds before organizing production to reduce the complexity of the problem.

2. Eliminate the impact of raw resin and masterbatch:

Control of raw materials is the key to completely solve the color difference. Therefore, especially in the production of light-colored products, the significant influence of the different thermal stability of the base resin on the color fluctuation of the product cannot be ignored. In view of the fact that most injection molding manufacturers do not produce plastic masterbatch or masterbatch itself, they can focus on production management and raw material inspection. alloy screw

That is, to strengthen the inspection of raw materials into storage; The same product should be produced by the same manufacturer as far as possible, with the same trademark masterbatch and masterbatch. As for masterbatch, we need to carry out sampling test before mass production, and use the previous correction to compare with this. If the color difference is not large, it can be considered qualified, just like the batch color masterbatch has a slight color difference, so we can mix the color masterbatch from the beginning, and then apply it to reduce the color difference caused by the uneven mixing of the color masterbatch itself. In addition, we also need to focus on the thermal stability of the material resin and masterbatch. For poor thermal stability, it is recommended that the manufacturer replace it.

3. Reduce the influence of barrel temperature on color difference:

In production, it is often encountered that the heating ring is damaged and invalid, or the heating control part burns out of control for a long time, resulting in drastic changes in barrel temperature and color difference. It is easy to judge the color difference caused by such reasons. Generally, the color difference caused by the damage and failure of the heating ring will be accompanied by the phenomenon of uneven plasticization. The heating control part of the uncontrolled combustion is often accompanied by product gas spots, serious discoloration and even coking. Therefore, in production, it is necessary to check the heating parts frequently, and replace and repair the heating parts in time when they are damaged or out of control, so as to reduce the occurrence probability of this color difference. alloy screw

4. Reduce the impact of injection molding process adjustment:

When the injection process parameters need to be adjusted for non-chromatic reasons, the injection temperature, back pressure, injection cycle, and masterbatch dosage should not be changed as much as possible. At the same time, the effect of process parameters on color should be investigated. If color difference is found, it should be adjusted in time. As far as possible to avoid high injection speed, high back pressure and other strong shear injection molding process, to avoid overheating or thermal differentiation and other factors caused by color difference. The temperature of each heating section of the barrel is strictly controlled, especially the nozzle and the heating part near the nozzle.

5. Master the barrel temperature and masterbatch pairalloy screwEffect of color change of products;

Before adjusting the color difference, it is necessary to understand the change trend of product color with temperature and masterbatch. Different masterbatch with the production temperature or the amount of different masterbatch changes, the product color change law is also different. The variation rules may be determined by a color testing process. Unless the color change law of this masterbatch is known, it is impossible to quickly adjust the color difference.