What factors affect the effectiveness of blow molding processing?

In the plastic industry, many companies consider using blow molding technology to produce hollow products in order to save costs. This greatly reduces costs compared to injection molding, and therefore, the blow molding process has also developed rapidly. Blow molded products are also widely applicable, such as in the toy industry, packaging industry, electrical industry, and other industries.

For blow molded products, raw materials are very important. When selecting raw materials, it is important to consider their performance and processing capabilities, and to meet the conditions and usage requirements of blow molded products. Common blow molding materials:

1.HDPE

2. PP

3. PET

4. LDPE

The position of the mold separation (closing line), product slope, product layout, inflation ratio, rounded corners, and appearance modification involved in the blow molding process need to be considered. The specific analysis is as follows:

1. Position of the mold line. Before opening the mold, it is necessary to carefully consider how to divide the mold, as this will affect the subsequent production and appearance of the product;

2. Product slope. All surfaces parallel to the direction of mold movement should have a certain slope, and the slope should be such that the mold can be easily opened for easy removal of the product;

3. Check all usage functions. When used as a product, it is better to have fewer components and assembly work, as it can reduce the cost of the product;

4. Inflation ratio. During inflation, pay attention to areas with extremely thin geometric shapes, which may be protruding or recessed. When the width to depth ratio is too large, vacuum forming can be used as an auxiliary method;

5. Principle of radius. Avoid sharp edges, corners, sudden changes in surface, sudden changes in product diameter or wall thickness;

6. The positions of inserts, exhaust slots, intake needles, top pin holes, engraving, and labels need to be carefully considered.

Controlling the temperature of the extruder is a key factor in the extrusion blow molding process. The adjustment of extrusion temperature is related to the blowing material. The temperature of extrusion can affect the quality of the product. When the extrusion temperature is too high, it can cause uneven wall thickness on the surface of blow molded products. When the extrusion temperature is too low, it will cause the surface of the embryo to become rough. So when manufacturing large blow molded products, the main focus is on preventing the embryo from sagging, and the temperature can be kept low. When making small blow molded products, the temperature needs to be higher.

The rotational speed of the screw is another important factor in the extrusion blow molding process. The speed of the screw can affect the quality of the embryo. When the extrusion speed is high, it can increase the yield and reduce the sagging of the embryo, but it can also lead to a decrease in the surface quality of the embryo. If the shear rate is too high, it may cause the plastic to dissolve and break.

In summary, whether it is a small blow molded product or a large blow molded product, the energy and time required before development cannot be reduced. It is necessary to carefully consider the factors that may affect the blow molding processing effect in order to match the appearance and function of each blow molded product well.