The working principle of a horizontal screen, also known as a horizontal vibrating screen, revolves around the concept of mechanical vibration and motion to separate, classify, and convey materials. Horizontal screens are commonly used in industries such as mining, construction, aggregate processing, and more for tasks like sizing, dewatering, and scalping of various materials.

The working principle of a horizontal screen:

1. Structure: A horizontal screen consists of a rectangular or slightly inclined box-like structure called a “deck.” The deck is mounted on a frame and is typically equipped with multiple screen layers or decks stacked on top of each other.

2. Vibration Mechanism: Horizontal screens use a vibration mechanism to generate the necessary motion for material separation. This mechanism is usually provided by one or more vibrators mounted on the sides of the screen. These vibrators generate oscillating or circular vibrations that cause the screen deck and the material on it to vibrate.

3. Material Loading: The material to be screened is fed onto the screen deck from the top or one end. The material spreads across the width of the deck, forming a thin layer.

4. Separation: As the screen deck vibrates, the material experiences a combination of vertical and horizontal motions. The vertical component lifts the material, allowing smaller particles to pass through the gaps in the screen mesh or openings. The horizontal motion propels the material forward along the deck.

5. Sizing and Classification: Depending on the size of the openings in the screen mesh, particles that are smaller than the openings will fall through and be collected as undersize material, while particles larger than the openings will remain on the screen and be collected as oversize material. This process classifies the material into different size fractions.

6. Decks and Multiple Layers: Horizontal screens often have multiple decks or layers of screens stacked on top of each other. Each deck may have different screen mesh sizes to further refine the material into different size categories.

7. Dewatering and Washing: Horizontal screens are also used for dewatering and washing applications. In these cases, the vibration aids in removing water or liquids from the material, helping to reduce moisture content.

8. Conveying: In some cases, horizontal screens are used to convey material from one point to another by exploiting the forward motion generated by the vibration.

9. Adjustability: The amplitude and frequency of the vibration can often be adjusted to optimize the screening process for different types of materials and desired outcomes.

10. Discharge: After the material has passed over the screen decks, it is collected and discharged into different chutes or conveyors based on its size and characteristics.

Horizontal screens are versatile and widely used due to their efficiency in separating various materials based on size. They are a crucial component in many material processing operations and play a significant role in industries ranging from mining and construction to aggregate production and recycling.

A double-deck screen, also known as a double-deck vibrating screen, is a piece of equipment used in the mineral processing and aggregate industries to separate and size particles or materials into different grades or fractions. The working principle of a double-deck screen involves the use of multiple decks, each with different-sized screens, to efficiently separate the material into two or more fractions based on their particle size.

The working principle of a double-deck screen

Material Feeding

The material to be screened is fed onto the top deck of the double-deck screen. This can be done using a conveyor belt, a chute, or other feeding mechanisms.

Screening Surfaces

A double-deck screen consists of two decks or levels, each with a different-sized screen opening. The top deck usually has larger openings or mesh size, while the bottom deck has smaller openings.

Vibrating Motion

The screen decks are mounted on a frame and are vibrated using a motor or vibrating mechanism. This vibration causes the material to move and spread across the surface of each deck.

Particle Separation

As the material spreads across the top deck, particles that are smaller than the openings in the top deck pass through and fall onto the bottom deck. The larger particles that cannot pass through the openings in the top deck continue moving towards the end of the screen.

Second Screening

On the bottom deck, the smaller particles that passed through the top deck’s openings are further separated based on their size. The finer particles fall through the openings in the bottom deck, while the larger particles remain on the screen surface.

Discharge

The separated fractions of the material are then discharged from the screen through different outlets. Usually, there are separate discharge chutes for each deck to collect the respective fractions.

By using two or more decks with different-sized screens, the double-deck screen can efficiently classify and separate the material into multiple fractions. This is particularly useful in applications where precise particle size control and classification are essential. The efficiency of a double-deck screen can be enhanced by adjusting the vibration amplitude, frequency, and angle of the screen decks to optimize the screening process for specific materials and production requirements.

A banana screen, also known as a multi-slope screen or multi-angle screen, is a type of vibrating screen used in the mining and aggregate industries. It is called a banana screen because of its shape, which resembles a banana curved in multiple angles. The banana screen offers several advantages over traditional horizontal or inclined screens:

High Capacity

Banana screens have a large screening surface area due to their multi-slope design. This design allows for efficient handling of high tonnages of material, resulting in higher capacity compared to other types of screens.

Efficient Screening

The unique shape of the banana screen enables effective screening of both wet and dry materials. The sloping decks facilitate the stratification of the material, allowing for better separation of finer particles. This improves the overall screening efficiency and product quality.

Improved Screen Performance

Banana screens are designed to handle challenging applications with high feed rates and large material sizes. They offer improved screen performance by reducing pegging and blinding issues. Pegging refers to the clogging of screen openings, while blinding occurs when material particles adhere to the screen surface, reducing the screening efficiency. The sloping decks of banana screens help prevent these problems, resulting in uninterrupted screening operation.

Reduced Vibrations

Banana screens are designed with a curved profile, which helps in distributing the vibrations evenly across the screen surface. This reduces the overall dynamic loads on the structure and improves the screen’s stability and durability. Reduced vibrations also contribute to a quieter operating environment.

Versatile Applications

Banana screens can be used for a wide range of applications, including primary and secondary screening of various materials such as ores, coal, aggregates, and industrial minerals. They are particularly suitable for screening high moisture and sticky materials, as well as for scalping and dewatering processes.

Customizable Configurations

Banana screens can be customized to meet specific application requirements. They can be designed with different deck angles, number of decks, and deck types (such as polyurethane or woven wire) to optimize the screening process for different materials and applications.

Overall, the advantages of banana screens make them a popular choice in industries where high capacity, efficient screening, and reliable performance are essential.

A single deck banana screen is a type of vibrating screen that is characterized by a curved or banana-shaped deck surface. It is designed to handle high-capacity applications and provide efficient screening and classification of materials. The unique shape of the deck allows for increased screening area and improved material distribution, leading to higher throughput and better separation efficiency.

Single deck banana screen specifications

Dimensions

Screen length: The length of the vibrating screen, typically measured in millimeters or inches.

Screen width: The width of the screen deck, determining the screening area.

Deck Design

Banana shape: The deck surface is curved or banana-shaped, with a steeper inclination towards the discharge end. This design allows for better material stratification and increased screening efficiency.

Number of decks: A single deck banana screen has one screen surface. However, multiple decks can be incorporated for finer classification and separation.

Motion and Operation

Vibrating mechanism: The type of vibrating motion generated by the screen, which can be circular, linear, or elliptical.

Drive type: The method used to generate the vibrating motion, such as electric motor, magnetic vibrator, or eccentric shaft.

Inclination angle: The angle at which the screen deck is inclined, which affects the material flow and screening efficiency.

Screen Mesh and Aperture

Mesh size: The size of the openings in the screen mesh, typically measured in microns, millimeters, or inches. It determines the particle size separation.

Wire diameter: The thickness of the wire used to create the screen mesh.

Capacity and Efficiency

Throughput or capacity: The maximum amount of material that the vibrating screen can handle per unit of time, typically measured in tons per hour (TPH) or cubic meters per hour (m³/h).

Screening efficiency: The percentage of material that passes through the screen compared to the total input material.

Construction and Materials

Screen frame: The framework that supports the screen panels and provides structural rigidity.

Screen panels: The individual sections of the screen that contain the screen mesh. They can be made of various materials such as woven wire, polyurethane, rubber, or perforated plate.

Single deck banana screens are commonly used in industries such as mining, quarrying, aggregate processing, and recycling. They are particularly suitable for applications that require high capacity screening, efficient material separation, and effective dewatering or desliming processes. It’s important to consult manufacturers or suppliers for specific technical details and options based on your requirements.

When operating a vibrating screen, it’s important to take certain precautions to ensure safe and efficient operation.

Precautions for operation of vibrating screen

Read the Operating Manual

Familiarize yourself with the manufacturer’s operating manual for the specific vibrating screen model you are using. The manual provides important instructions and guidelines for safe operation.

Wear Proper Personal Protective Equipment (PPE)

Always wear appropriate PPE, such as safety glasses, gloves, and hearing protection, when operating or working near a vibrating screen. This will help protect you from potential hazards, including flying debris and excessive noise.

Conduct Pre-Operation Inspection

Before starting the vibrating screen, visually inspect the machine for any signs of damage or wear. Check for loose bolts, damaged screens, and any abnormalities. Ensure that all guards and safety devices are in place and functioning properly.

Securely Mount and Level the Screen

Make sure the vibrating screen is securely mounted on its support structure or floor and properly leveled. This helps prevent excessive vibrations, ensures smooth operation, and minimizes stress on the machine.

Monitor Vibrating Screen Performance

Regularly monitor the performance of the vibrating screen during operation. Pay attention to unusual vibrations, noises, or changes in screening efficiency. If any issues arise, promptly shut down the machine and address the problem.

Maintain Proper Lubrication

Follow the manufacturer’s recommendations for lubrication. Proper lubrication helps reduce friction and wear, extending the lifespan of components and ensuring smooth operation.

Avoid Overloading

Do not overload the vibrating screen beyond its designed capacity. Overloading can cause excessive stress on the machine and lead to premature wear or failure of components.

Clean and Maintain the Screen

Regularly clean the screen to prevent material buildup, which can affect screening efficiency. Additionally, perform routine maintenance tasks, such as tightening bolts, inspecting screens for wear, and replacing damaged or worn parts.

Follow Lockout/Tagout Procedures

When performing maintenance or repairs on the vibrating screen, follow lockout/tagout procedures to ensure the machine is de-energized and cannot be started accidentally.

Seek Expert Assistance when Needed

If you encounter any operational issues or are unsure about any aspect of the vibrating screen’s operation, seek assistance from qualified personnel or contact the manufacturer for guidance.

By following these precautions, you can help ensure safe operation, maximize the lifespan of the vibrating screen, and maintain efficient screening performance.