What is a Feeder?
A feeder is a piece of auxiliary equipment used to control the flow rate and conveying speed of materials. It is widely used in industries such as mining, metallurgy, building materials, chemicals, and coal. Its main function is to feed bulk materials from a hopper or stockpile uniformly, continuously, or in measured quantities into crushers, conveyors, or screening equipment. The feeder is the first piece of equipment in a crushing and screening production line, and its operational stability directly affects the efficiency and capacity of the entire line.
Types of Feeders
Vibrating Feeder: The most common feeding equipment. It uses the exciting force generated by vibrating motors or eccentric blocks to vibrate the trough, driving material to move forward in a jumping motion. It has a simple structure, uniform feeding, and good adjustability.
GZD Series Vibrating Feeder: Driven by two vibrating motors, widely used in crushing and screening lines in mining, metallurgy, building materials, and other industries.
ZSW Series Vibrating Feeder: Driven by an eccentric shaft vibrator, offering stable amplitude and large feeding capacity, commonly used for feeding before primary crushing.
Apron Feeder: Composed of a drive unit, sprockets, chains, and pans. The pans carry the material, which is transported by the chain drive. It can withstand huge material column pressures and is suitable for conveying large blocks, heavy loads, and high-temperature materials, commonly used for feeding before primary crushing in mines.
Light-Duty Apron Feeder: Suitable for conveying materials with lower specific gravity and smaller block sizes.
Medium-Duty Apron Feeder: Suitable for conveying materials with medium specific gravity and moderate block sizes.
Heavy-Duty Apron Feeder: Suitable for conveying materials with high specific gravity, large block sizes, and high temperatures, such as feeding before primary crushing in mines.
Electromagnetic Vibrating Feeder: Uses an electromagnetic vibrator to drive the trough into high-frequency vibration, achieving material conveying. It has a simple structure, no rotating parts, high feeding accuracy, and allows stepless adjustment, making it suitable for quantitative feeding and batching.
Reciprocating Feeder: Uses a reciprocating feed plate to push material out from the bottom of the hopper. It has a simple structure and low cost, suitable for materials with low stickiness and uniform particle size.
Rotary Table Feeder: Consists of a rotating table and a scraper. Material falls from the hopper onto the rotating table and is scraped off by the scraper. It offers uniform feeding and easy adjustment, suitable for quantitative feeding of powdery and small granular materials.
Screw Feeder: Uses a rotating screw blade to push material. It has a compact structure and good sealing, suitable for enclosed feeding of powdery and small granular materials.
Belt Feeder: An improvement based on belt conveyors, controlling the feed rate by adjusting the belt speed. It has a simple structure, long conveying distance, and is suitable for various loose materials.
Key Features of Feeders
Uniform Feeding: Achieves uniform and continuous material feeding, ensuring stable operation of downstream equipment.
Easy Adjustment: The feed rate can be easily adjusted by changing the vibration frequency, amplitude, rotational speed, or valve opening.
Strong Adaptability: Can handle materials of different particle sizes, temperatures, and moistures, ranging from powders to large blocks.
Compatible with VFD: Equipped with a Variable-frequency Drive, it enables stepless adjustment of the feed rate for precise process control.
Can Include Pre-Screening Function: Some vibrating feeders (e.g., GZD, ZSW series) have grizzly bars at the front of the trough, allowing for pre-screening of materials to separate fines and improve crushing efficiency.
Diverse Structures: Different types of feeders can be selected based on site space and process requirements.
Feeder Customization Options
Manufacturers often offer custom configurations based on specific material characteristics and process requirements:
Trough Size: Trough length and width can be customized based on throughput requirements.
Grizzly Bar Spacing: For feeders with a pre-screening function, the gap between grizzly bars can be customized to separate fines of different sizes.
Exciting Force Adjustment: The angle of eccentric blocks in vibrating motors or the counterweight of vibrators can be adjusted to change the exciting force.
Drive Type: Options include vibrating motor drive, eccentric shaft vibrator drive, or electromagnetic drive.
Wear-Resistant Liners: The inner wall of the trough can be fitted with wear-resistant liners based on material abrasiveness to extend service life.
Sealing and Dust Prevention: Dust covers can be added to reduce dust emission and improve the working environment.
Feeder Supplier
PASCAL is a professional feeder supplier, with its factory established in 2017, based in Luoyang, China. The company serves as a global supplier of heavy industrial machinery, specializing in crushing and screening equipment and various machinery used in the mining and construction sectors. They provide various feeding equipment including vibrating feeders, apron feeders, and electromagnetic vibrating feeders to meet feeding needs under different working conditions.
Feeder FAQ
How to choose between a vibrating feeder and an apron feeder?
Vibrating feeders have a simple structure and low cost, suitable for small to medium blocks and materials with low abrasiveness. Apron feeders can withstand huge impact and material column pressure, suitable for large blocks, heavy loads, high temperatures, and highly abrasive materials, but have a higher cost. For feeding before primary crushing of large run-of-mine ore, apron feeders are typically chosen; for crushing small to medium-sized gravel and aggregates, vibrating feeders are commonly used.
How is the feed rate adjusted?
For vibrating feeders, the feed rate can be adjusted by changing the vibrating motor speed or the angle of eccentric blocks to alter the exciting force. For electromagnetic vibrating feeders, the amplitude can be adjusted by changing the current. For apron feeders, the feed rate can be adjusted by changing the drive motor speed to alter the pan speed.
What to do if the feeder gets clogged?
Possible causes include: feed rate exceeding equipment capacity; sticky or high-moisture material; trough or chute angle too small; grizzly bar spacing too small, causing material to jam. Solutions: reduce the feed rate, clear the blockage, adjust the trough angle, increase grizzly bar spacing. For sticky materials, consider installing anti-clogging vibration devices.
What causes excessive noise from a vibrating feeder?
Possible causes include: damaged vibrating motor bearings; improper adjustment of eccentric blocks causing excessive exciting force; broken or失效 springs; loose connecting bolts on the trough or support structure; collision between the trough and surrounding structures.
What to do if the apron feeder chain deviates (tracks off-center)?
Causes may include uneven chain tension, uneven sprocket wear, or frame deformation. Solutions: adjust the tensioning device to ensure consistent chain tension on both sides; replace severely worn sprockets; correct the frame alignment.
What causes reduced amplitude or no vibration in an electromagnetic vibrating feeder?
Possible causes include: controller malfunction or damage; burnt or short-circuited electromagnetic coil; air gap too large or too small; broken leaf spring; low power supply voltage.
What is a Screen?
A screen (screening equipment) is a device used to classify mixed materials of different particle sizes by separating them based on size. It is widely used in industries such as mining, metallurgy, building materials, chemicals, food, and pharmaceuticals. Its working principle is based on screen surface vibration and the ability of particles to pass through screen apertures: material on the screen surface is subjected to vibratory forces, causing stratification and passage through the screen. Fine particles smaller than the screen aperture pass through to become undersize, while coarse particles larger than the aperture move forward along the screen surface to become oversize.
Types of Screens
Circular Vibrating Screen: The screen box motion trajectory is circular or elliptical. It has a simple structure, high screening efficiency, and large processing capacity, making it the most common screening equipment in mines and quarries. Suitable for screening large and medium-sized materials.
YK Series Circular Vibrating Screen: Uses block eccentric vibrators with adjustable amplitude, offering high screening efficiency and large processing capacity.
Linear Vibrating Screen: The screen box motion trajectory is linear. Driven by dual vibrating motors or dual vibrators, it provides large exciting force and high screening efficiency. Suitable for dewatering, media recovery, desliming, and classification of fine materials.
High-Frequency Screen: Features high vibration frequency and low amplitude, used for efficient screening of fine materials, improving screening efficiency and throughput. Commonly used in fine screening, regrinding, or pre-concentration in grinding-classification circuits of concentrators.
Banana Screen: The screen surface is banana-shaped (multi-sloped). Material moves faster initially and then slower on the screen surface, thinning the material bed, which facilitates fine particle penetration. It offers large processing capacity and high screening efficiency, suitable for classification tasks with high throughput.
Trommel Screen (Rotary Screen): The screen surface is cylindrical or conical. The cylinder rotates, tumbling the material. Fine particles pass through the screen, while coarse particles are discharged from the end. It has a simple structure and stable operation, suitable for handling sticky and wet materials, commonly used in sand and gravel washing, waste processing, etc.
Probability Screen: Uses multiple layers of steeply inclined screen surfaces with apertures much larger than the cut point. It utilizes probability principles for rapid screening. It offers large processing capacity and a small footprint, suitable for rough classification or high-throughput applications.
Flip-Flop Screen: The screen surface is made of elastic polyurethane material. The reciprocating motion of the screen frame causes the screen surface to flex and tension, generating high acceleration and providing excellent anti-clogging performance. Suitable for handling sticky and wet fine materials such as coal and coke.
Air Classifier Screen: Uses airflow to disperse material and pass it through the screen mesh. Suitable for screening ultra-fine powders, offering high screening efficiency and no dust pollution.
Key Features of Screens
Accurate Classification: Screen meshes with different apertures can be replaced as needed to achieve precise particle size classification.
High Screening Efficiency: Through reasonable vibration parameters and screen surface design, material is fully stratified and passes through the screen, achieving high screening efficiency.
Large Processing Capacity: Large vibrating screens can have a single-unit processing capacity of hundreds or even thousands of tons per hour.
Diverse Structures: Screening equipment with different motion trajectories and structures can be selected based on material characteristics and process requirements.
Multi-Layer Screening: Multiple screen decks can be designed to simultaneously produce several size fractions.
Long Screen Life: Screen meshes made from high-quality wear-resistant materials, combined with reasonable vibration parameters, extend service life.
Screen Customization Options
Manufacturers often offer custom configurations based on specific material characteristics and process requirements:
Number of Decks: Single-deck, double-deck, triple-deck, or multi-deck screens can be customized as needed.
Screen Mesh Type: Screen meshes of different materials and structures can be selected, such as woven wire mesh, punched plate, polyurethane panels, and rubber panels.
Screen Aperture Shape and Size: Apertures of different shapes (round, square, slotted) and sizes can be customized.
Vibration Method: Options include block eccentric vibrators, shaft eccentric vibrators, or vibrating motor excitation.
Amplitude and Frequency: Amplitude and vibration frequency can be adjusted based on material characteristics to optimize screening performance.
Installation Angle: The screen surface installation angle can be adjusted as needed to suit the flowability of different materials.
Screen Supplier
PASCAL is a professional screening equipment supplier, with its factory established in 2017, based in Luoyang, China. The company serves as a global supplier of heavy industrial machinery, specializing in crushing and screening equipment and various machinery used in the mining and construction sectors. They provide various screening equipment including circular vibrating screens, linear vibrating screens, and high-frequency screens to meet the classification, dewatering, and media recovery needs under different working conditions.
Screen FAQ
What is the difference between a circular vibrating screen and a linear vibrating screen?
A circular vibrating screen has a circular motion trajectory, causing material to jump and tumble on the screen surface, which aids stratification, making it suitable for classifying large and medium-sized materials. A linear vibrating screen has a linear motion trajectory, causing material to be thrown forward on the screen surface, which aids dewatering and media recovery, making it suitable for classifying and dewatering fine materials.
What to do if the screen mesh gets clogged?
Common causes of clogging: sticky or high-moisture material; improper screen aperture selection; excessive feed rate; insufficient screen tension. Solutions: choose anti-clogging screen meshes (e.g., flip-flop screens, polyurethane panels); adjust vibration parameters; reduce feed rate; increase screen tension. For sticky materials, consider installing screen cleaning devices (e.g., rubber balls, slapping devices).
What causes low screening efficiency?
Possible causes include: worn or damaged screen mesh, causing enlarged or deformed apertures; uneven feeding, resulting in a thick material bed; inappropriate screen surface inclination angle; improper vibration parameters (low amplitude, low frequency); clogged screen mesh; high material moisture content causing agglomeration.
What to do if the vibrating screen is excessively noisy?
First, check if connecting bolts on screen components are loose. Check if springs are broken or have failed. Check if bearings in vibrating motors or vibrators are damaged. Check the screen box for cracks. Check if the screen mesh is insufficiently tensioned and slapping against the screen box.
What to do if the screen box motion trajectory is abnormal?
Possible causes include: poor synchronization of vibrating motors or vibrators (for linear screens); inconsistent exciting force adjustment, leading to unbalanced forces on both sides; inconsistent spring support stiffness; deformation of the screen box structure.
What causes bearing overheating?
Possible causes include: too much, too little, or contaminated/deteriorated grease; improper bearing installation with insufficient clearance; bearing wear or damage; excessive exciting force exceeding bearing load capacity; damaged labyrinth seals allowing dust to enter bearings.
