5 Core Crushing Methods + Comprehensive Analysis of Working Principles for Sand Making Equipments: Master the Core Logic of Sand Making in Seconds!

In the current sand making industry, machines are available in diverse types with distinct working principles—factors that directly impact production capacity and are closely tied to customers' investment returns. This article will elaborate on the 5 crushing methods and their corresponding working principles of two common categories of sand making machines.

VSI crushers (also referred to as vertical shaft impact crushers) adopt two crushing methods: "rock-on-rock" and "rock-on-steel". The feeding methods of vertical shaft impact crushers are divided into "full center feeding" and "center feeding with cascade feeding".

Materials enter the rotor of the vertical shaft impact crusher through the feed hopper. The high-speed rotating rotor of the VSI crusher ejects the materials, which strike the impact plates and rebound. During the descent, the rebounded materials collide with those subsequently ejected from the rotor of the vertical shaft impact crusher. Through multiple impacts and friction within the crushing chamber of the VSI crusher, the materials are crushed. Finally, under the action of gravity, the crushed materials exit the crushing chamber and enter the discharge hopper of the lower casing of the vertical shaft impact crusher for discharge.

Materials enter the rotor of the vertical shaft impact crusher through the feed hopper. The high-speed rotating rotor of the vertical shaft impact crusher ejects the materials, which strike the peripheral guard plates and are crushed. Under the action of gravity, the crushed materials exit the crushing chamber and enter the discharge hopper of the lower casing of the VSI crusher for discharge.

Materials enter the vertical shaft impact crusher through the feed hopper, fall onto the material separating plate via the material distributing cone, and are divided into two parts. One part enters the high-speed rotating impeller from the center of the material separating plate of the VSI crusher, is rapidly accelerated inside the impeller, and then ejected at high speed from the impeller flow channels. These materials first collide and crush with the other part of the materials falling around the material separating plate, then jointly impact the material lining layer of the crushing chamber of the vertical shaft impact crusher. After rebounding, they obliquely strike the top of the crushing chamber, change direction to move downward, and form a continuous material curtain with the materials ejected from the impeller flow channels of the VSI crusher. Thus, a single piece of material is crushed through multiple impacts, friction, and grinding inside the crushing chamber of the vertical shaft impact crusher.

The basic working principle of this VSI crusher is identical to that of the "Rock-on-Rock" mode in vertical shaft impact crushers with center feeding and cascade feeding. The key difference lies in the internal components of the crushing chamber of the vertical shaft impact crusher: for the "rock-on-rock" mode, the chamber of the VSI crusher is equipped with impact plates, around which materials form a lining layer, and crushing occurs when materials impact this material lining layer. In contrast, for the "rock-on-steel" mode of the vertical shaft impact crusher, the lower impact plates are replaced with peripheral guard plates, and materials are directly crushed by impacting these peripheral guard plates of the VSI crusher.

Vertical Shaft Impact Crusher (VSI Crusher)

◆Generally, full center feeding is mainly paired with the "rock-on-steel" mode, typically used for sand making with lower production capacity. In contrast, center feeding combined with cascade feeding integrates both "rock-on-steel" and "rock-on-rock" modes, primarily applied for aggregate shaping with higher production capacity.

◆The "rock-on-rock" crushing method of VSI crusher is suitable for materials with high abrasiveness and hardness above the medium grade, such as basalt. During the crushing process, materials ejected from the impeller collide with the material lining layer instead of directly contacting the metal components of the VSI crusher. This reduces iron consumption, thereby minimizing maintenance time. Additionally, the "rock-on-rock" mode yields finished products with excellent particle shape.

◆The "rock-on-steel" crushing method of vertical shaft impact crusher is applicable for materials with low abrasiveness and hardness below the medium grade, such as limestone. Notably, the "rock-on-steel" mode offers higher crushing efficiency.

Hammer sand making machines achieve sand making through hammer impact and the "rock-on-rock" principle, primarily designed for crushing materials of medium hardness. With its simple structure and low operating cost, this type of sand making machine has been widely favored by customers since its launch.

Specific Working Process:

After materials enter the chamber of the hammer sand making machine, they are first struck by the hammers arranged in parallel on each rotor. Subsequently, the materials rush at high speed toward the second rotor—since the movement direction of the hammers on this rotor is opposite to the material impact direction, the impact speed exerted on the materials is equivalent to the superposition of two speeds, ensuring full crushing. The materials are continuously crushed until they meet the required particle size, and finally discharge through the gaps of the sieve plate.

The above covers the five common working principles of sand making machines, including those of VSI crusher (vertical shaft impact crusher) and hammer sand making machines. Hope this will help you choose the most appropriate equipment tailored to your specific production needs.