Optimization of pet food extruder screw structure: improving material handling efficiency and quality

1. Basic function of screw structure
The screw plays multiple roles in pet food extruder machines. First of all, it is the main driving force for material transportation, gradually pushing the raw materials from the feed port to the discharge port through rotation. Secondly, the spiral groove design of the screw promotes the mixing of materials so that different ingredients can be evenly distributed, which is crucial for the nutritional balance of pet food. Finally, the shearing effect of the screw can change the physical state of the material, such as particle size, density and shape, to adapt to different product needs. However, excessive shearing may lead to problems such as loss of nutrients, poor taste, and increased energy consumption.

2. Advantages of twin-screw structure
In response to the limitations of the traditional single-screw structure, the twin-screw structure emerged as the times require and shows significant advantages in pet food production. The twin screw consists of two intermeshing screws. The complex channel formed between them not only increases the contact area between the material and the screw, but also provides more mixing and shearing opportunities, but more importantly, through precise design, Unnecessary shearing can be greatly reduced.

Reduced shear range: The twin-screw structure can achieve gentler processing of materials by precisely controlling the gap and speed ratio between the two screws. Compared with single screws, twin screws can ensure necessary shear while reducing the occurrence of excessive shear, protecting sensitive components in raw materials, such as proteins, vitamins and fats, from degradation due to high temperature and excessive mechanical action.
Improved pumping effect: The tight fit of the twin screws enhances the forward driving force of the material, maintaining a stable material flow even under high-pressure conditions, and reducing the risk of backflow and blockage. This efficient pumping effect ensures the continuity and uniformity of materials during the extrusion process, which is beneficial to the stability and efficiency of the production process.
Optimize the mixing effect: The complex channel design of the twin screws promotes multi-directional flow and shear mixing of materials, allowing different raw materials to be more fully integrated to achieve ideal nutritional ratios and taste effects. This is critical to producing high-quality, nutritionally balanced pet food.
3. Practical application and future prospects
In practical applications, twin-screw extruders have been widely used in the pet food industry, especially in the production of high-end pet foods, such as pet cans, pet biscuits, and pet wet food. By precisely controlling screw parameters, such as pitch, speed and material, manufacturers can produce pet food with specific shapes, textures and nutritional values ​​to meet the special needs of different pet breeds and age groups.

In the future, as the pet food market continues to be segmented and consumers pay more attention to pet health, further optimization and innovation of screw structures will become an important direction for industry development. For example, the use of intelligent control systems to dynamically adjust screw parameters and the development of new wear-resistant and corrosion-resistant screw materials will bring revolutionary changes to pet food production.