Optimization of Brick Making Process Parameters: Matching Pressure and Vibration Modes Based on Material Rheological Properties

Optimization of Brick Making Process Parameters: Matching Pressure and Vibration Modes Based on Material Rheological Properties

In brick making, the process of pressing a mixture (such as cement, aggregate, and waste residue) into brick blanks is crucial. The core of its optimization lies in scientifically matching the molding pressure and vibration mode according to the mixture's own flow deformation characteristics, such as hardness, dryness, wetness, and viscosity, to achieve rapid, dense, and uniform molding. This is key to ensuring the stable strength and quality of the brick blanks.

The molding pressure setting needs to be balanced. If the raw material is dry, coarse-grained, and has poor flowability, a larger pressure is required to forcefully compress the particles and expel air. Conversely, if the raw material is wet, fine, and has good flowability, excessive pressure can easily lead to material leakage or excessive extrusion of internal moisture, damaging the structure. In this case, the pressure should be appropriately reduced or a segmented pressing mode of "light pressure first, then heavy pressure" should be adopted. The goal of pressure optimization is to ensure that the material fully fills the corners of the mold cavity to achieve maximum density, while avoiding unnecessary wear and tear on the mold and equipment.

The selection of the vibration mode needs to be tailored to the specific material. The purpose of vibration is to "activate" material particles, allowing them to rearrange to their densest state under the influence of gravity and inertia. For mixtures containing a large amount of coarse aggregate and prone to segregation, vibration with a larger amplitude and lower frequency is suitable to promote the movement and positioning of large particles. For mixtures with a high proportion of fine powder and high viscosity, high-frequency, small-amplitude vibration is suitable, using high-frequency micro-vibration to break down the binding forces between particles, allowing them to flow and compact better. The vibration duration also needs precise control; too short a duration results in uneven compaction, while too long a duration may lead to particle stratification.

The synergy of pressure and vibration is the most efficient approach. The most advanced processes often employ a combination of static pressure and vibration. For example, a certain amount of static pressure is first applied to initially shape the material and expel most of the air, then vibration is added to further compact the internal particles; or a certain amount of pressure is maintained while vibrating to achieve dynamic compaction. Through repeated experiments, the optimal pressure value, vibration parameters (frequency, amplitude, time), and combination of the two for a specific raw material ratio were found. This can significantly improve the uniformity, appearance quality, and final strength of the brick blank, while shortening the molding cycle. It is a core technology for improving the efficiency and quality of brick production lines.