Indirect extrusion is a variant of the extrusion process in which the material to be extruded remains stationary while the die (or mold) moves in the opposite direction to the applied force, forcing the material to pass through it. This process reduces friction between the material and the container, enabling more efficient processing of materials with specific mechanical properties or those sensitive to deformation.
Characteristics of Indirect Extrusion
- Reduced Friction: Since the material stays stationary and does not slide along the walls of the container, friction is significantly reduced, improving the quality of the finished product and extending the lifespan of the molds.
- Energy Efficiency: Lower friction reduces the amount of force needed to extrude the material, making indirect extrusion a more energy-efficient process compared to direct extrusion.
- Greater Product Homogeneity: Reduced mechanical stress on the material allows for products with better physical properties, such as a more uniform structure.
When Is Indirect Extrusion Used?
Indirect extrusion is used in various industrial applications, particularly when it's important to reduce tool wear and improve the quality of the processed material:
- Processing Delicate Materials: Used for metals and polymers that could be damaged or deformed if subjected to excessive mechanical stress.
- Production of Tubes and Hollow Cylinders: The indirect process is particularly suitable for producing tubes and other hollow components, as it improves uniformity and reduces defects.
- High-Strength Materials: Suitable for materials that are difficult to process and require high force to be deformed.
