Single Shaft Shredder

Working principle

The operation of a single-shaft shredder relies on a continuous process of "power drive - material conveying - shearing and crushing - finished product discharge." This process revolves around the coordinated operation of the single cutter shaft and its associated components. Its working principle can be broken down into the following key steps.

1. Power Transmission System Startup

After the machine is started, the motor, acting as the power source, begins to rotate, transmitting power to the reduction gearbox via a coupling. The reduction gearbox converts the motor's high-speed rotation into the low-speed, high-torque output required by the cutter shaft, ensuring sufficient shear force during the crushing process. Some high-end models are equipped with a variable frequency control system that adjusts the motor speed in real time according to material hardness, enabling precise adaptation of power output. Simultaneously, an overload protection device is activated to immediately cut off power if an anomaly such as material jamming occurs in the subsequent crushing process, preventing damage to the equipment.

2. Material Conveying and Induction

Material to be crushed enters the machine via a conveyor belt, feed hopper, and other devices. The feed inlet is typically designed with an inclined or forced feed mechanism. Small materials can slide down by their own weight, while large or sticky materials are pushed by a pusher, ensuring stable entry into the crushing zone. Some equipment incorporates a pre-treatment device at the feed inlet to initially shape the material and prevent feed blockage caused by material accumulation.

3. Core Shearing and Crushing Process

This is the key operating step in a single-shaft shredder. Multiple sets of staggered moving blades are evenly arranged on the blade shaft, creating a small shear gap with the fixed blades fixed to the inner wall of the shredder. When material enters the gap between the moving and fixed blades, the high-speed rotation of the moving blades, coupled with the high torque transmitted by the reduction gearbox, creates tearing, shearing, and squeezing forces on the material.

The crushing mechanisms vary slightly depending on the material: For flexible materials like plastic and rubber, the staggered shearing of the moving and fixed blades quickly rips them into small pieces; for hard materials like wood and hard plastics, a combination of squeezing and shearing is used to crush them. The blade tooth profile, material, and shear gap can be adjusted according to the material's characteristics to ensure precise and controllable crushing results.

4. Product Screening and Discharge

The shredded material is screened. Finished products that meet the required particle size fall through the gaps in the screen onto the discharge conveyor below and are transported to a designated collection device. Materials that do not meet the particle size standard remain in the crushing area, undergoing further shearing by the rotating and fixed blades until they meet the required particle size and are discharged. The screen aperture can be changed as needed, flexibly controlling the finished product particle size and adapting to different subsequent processing requirements.

Throughout the entire operation, all systems work together to form a closed loop from power supply to finished product discharge. This ensures both efficient crushing and precise material processing, and is the core technology behind the widespread application of single-shaft shredders in solid waste management.