Why do we need three stages of blower cooling for WPC granulation machine
The Yongte Wood Plastic WPC granulation Machine equiip with three-stage blower cooling system, specifically designed to address the unique characteristics of wood-plastic pellets (including wood fibers, high-temperature adhesion tendency, and the need for impurity removal and purification). This system resolves the four core challenges of "cooling + impurity removal + stable conveying + product protection" that single-stage or two-stage pneumatic conveying cannot simultaneously achieve, ultimately meeting the continuous production requirements for wood-plastic pellet manufacturing.
The key process of WPC granulation: extrusion and granulation → cooling of granules → secondary crushing → storage of finished products.
The three stages of blower cooling system is not simply "send twice", but through the fan pressure gradient, separation structure difference and cooling path design, the integration of "transportation + processing" is realized. The specific division of labor is as follows:
|
Wind speed class |
key role |
Targeted production pain points |
Key design details |
|
Level 1 (high temperature primary transport) |
1. Quickly remove the high temperature particles (80-120℃) just squeezed out of the machine head from the high temperature environment; 2. Preliminary cooling (cooling to 50-60℃ through air temperature difference); 3. Separation of large size debris (e.g., long strips produced by wear of granulation knives) |
1. The particles stay too long near the high temperature head, and are easy to stick together; 2. If large pieces of material enter the subsequent process, they will block the pipeline or affect the appearance of finished products |
1. Use high temperature resistant fan (avoid high temperature particles damage fan); 2. Pipeline with coarse screen separator (particle size 5-8mm, intercept large debris); 3. The air temperature is controlled at room temperature (25-30℃), and the rapid cooling is achieved by temperature difference |
|
Level 2 (deep cooling + fine separation) |
1. Further reduce the particle temperature to 30-40℃ (close to room temperature to avoid subsequent adhesion); 2. Separation of fine dust/wood fiber debris (the wood fiber in wood plastic is easy to produce fine powder during granulation); 3. Secondary screening of small and medium size impurities (such as metal chips, plastic coke particles) |
1. The particle temperature does not drop to room temperature, and it will stick due to residual heat after entering the warehouse; 2. The fine dust mixed into the finished product will affect the surface smoothness of the subsequent extruded profiles (such as wood-plastic flooring, guardrail) |
1. Use medium pressure fan (moderate wind speed to avoid blowing up particles); 2. Cyclone separator + fine filter screen (filter screen aperture 1-2mm, separation of fine powder); 3. The pipeline can be equipped with cooling sleeve (cooling water is passed to enhance cooling) |
|
Level 3 (smooth entry into the warehouse + finished product protection) |
1. Smoothly convey the cooled and cleaned particles to the finished material bin; 2. Avoid particle crushing caused by transportation impact (the wood-plastic particles contain fibers and are slightly more brittle than pure plastics); 3. Final impurity removal (small amount of residual fine powder) |
1. The height of the material warehouse is high (usually 3-5m), and the single-stage high-pressure conveying is easy to cause the particles to collide with the wall of the warehouse and break; 2. Residual fine powder affects the purity of finished product packaging |
1. Use low pressure fan (low wind speed, stable wind pressure, more gentle transportation); 2. The end of the pipeline is equipped with buffer hopper (to reduce the impact of particles entering the warehouse); 3. Add powder bag at the entrance of material storage (to adsorb the last residual fine powder) |
The three stages of blower cooling system of the Yongte WPC granulation machine is essentially a "high-efficiency conveying system with functional subdivision" ——. Through the step-by-step design of "primary cooling → deep cooling → stable storage to ensure finished products", the core problem of "incomplete cooling" in wood-plastic particles is solved, and finally achieve:
Production efficiency: no additional cooling equipment (such as cooling water tank) and screening equipment is required to realize the "granulation-transportation-finished product" closed loop, and the production capacity is increased by 20-30%;
Finished product quality: adhesion rate <0.1%, meet the processing requirements of high-end wood-plastic products;
Cost control: Reduce manual intervention (such as breaking up adhered particles, manual screening), and reduce raw material loss by 4-5%.
Therefore, three-stage air delivery is not an "over-engineering", but a "customized solution" for the characteristics of wood plastic particles, and it is the key to ensure the continuous, stable and high-quality production of wood plastic particles.
