Vibration Screener Machine

Working Principles

1. Circular Vibrating Screen (Rotary Vibrating Screen) Working Principle: A vertically mounted vibrating motor serves as the excitation source. Eccentric blocks at both ends of the motor convert the rotational motion into a three-dimensional composite motion (horizontal, vertical, and inclined), which is then transmitted to the screen surface. After entering the screen box, the material spreads outward in a spiral pattern on the screen surface. Fine materials pass through the mesh and coarse materials are discharged from the discharge port along the edge. By adjusting the phase angle of the upper and lower eccentric blocks, the trajectory and residence time of the material on the screen surface can be changed.
2. Linear Vibrating Screen Working Principle: Utilizes dual vibrating motors rotating synchronously in opposite directions. The components of the forces of the two motor eccentric blocks in the direction parallel to the motor axis cancel each other out, and in the direction perpendicular to the motor axis, they are superimposed into a resultant force, causing the screen box to perform a reciprocating throwing motion in a straight line. The material is thrown up and jumps forward, achieving rapid linear screening. The screen surface inclination angle is typically 0°-15°. A larger inclination angle results in a larger throughput, but a decrease in screening accuracy.
3. Gyratory Screen Working Principle: A special vibration exciter generates nonlinear three-dimensional motion, simulating the low-speed swaying motion of a manual sieve. The material undergoes a combined radial displacement and circular motion (spiral motion) on the screen surface, which is particularly suitable for spherical, flaky, irregular, and fragile materials, and the screening accuracy can reach 90%-99%.

Equipment Capacity Range

1. Linear Vibrating Screen (Mainstream Fine Processing Screening)

2. Circular Vibrating Screen (Raw Material Coarse Screening) Hourly processing capacity 5~40t, single-layer large-aperture screen, mostly used for pre-treatment of impurities in fermentation raw materials.

Applications and Applicable Raw Materials

Vibrating screens are highly adaptable and can process a wide range of materials with particle sizes from 0.01 mm ultrafine powder to 300 mm large pieces:

Applications in Fertilizer Production Lines

1. Raw Material Pretreatment: Screening removes large impurities from raw materials, protecting subsequent crushers and granulators.
2. Finished Product Grading: After granulation/drying, the finished product is separated into three streams using a multi-layer vibrating screen: qualified granules, fine powder return material, and large particle return material. Fine powder and large particles are returned to the granulation and crushing processes respectively, achieving closed-loop utilization of raw materials.
3. Pre-Packaging Impurity Removal: Ensures uniform particle size of the finished product entering the packaging machine, improving product appearance quality.

Common Faults, Causes, and Standardized Solutions

Standard Operating Procedures and Full-Cycle Maintenance

(I) Start-up and Shutdown Procedures

1. Start-up: Must be started under no-load; before starting, tighten all screen frame and motor bolts, check for broken springs and screen tension; run under no-load for 3 minutes, observe amplitude and noise levels, then feed material evenly, prohibiting large-scale instantaneous feeding;
2. Shutdown: First shut down the upstream conveyor equipment, completely empty the material from the screen surface before disconnecting power, strictly prohibiting stopping the machine with material on, which could overload the motor.

(II) Graded Maintenance Procedures

1. Daily Inspection: Clean the screen of fertilizer blockage, check for cracks in the vibration damping springs, and observe the motor temperature rise to ≤60℃;
2. Weekly Maintenance: Add special vibration grease to the vibrating motor bearings, and tighten the eccentric block counterweight bolts;
3. Quarterly Maintenance: Disassemble the screen frame to thoroughly clean accumulated fertilizer, check screen wear and the integrity of the bouncing balls;
4. Annual Overhaul: Replace aging springs and damaged screens, and test the insulation performance of the vibrating motor. (III) List of vulnerable parts: Polyurethane/manganese steel screen, rubber vibration damping spring, vibration motor bearing, bouncing cleaning ball, sealing dustproof strip.

Analysis of the advantages and disadvantages of vibrating screens