In the world of material handling, two popular methods of conveying bulk solids are vibration conveying and screw conveying. Vibration conveying utilizes principles of vibration, while screw conveying utilizes principles of rotation. Although both conveyors are capable of efficiently handling bulk solids, they differ in terms of design, operation, and advantages. In this article, we’ll explore the differences between the two methods to help you choose the system that’s right for your operation.
Vibration Conveying
Vibration conveying is a method of moving bulk solids through the use of vibratory conveyors. Vibratory conveyors rely on the principles of vibration to transport materials along the conveyor path. The conveyor pan is designed to vibrate, shaking the particles and leading them toward the discharge point. This efficient mode of conveying often results in gentle handling of materials, making it an ideal solution for fragile materials.
Screw Conveying
Screw Conveying, also known as screw conveyors, rely on rotating the screw to transport the bulk material from one end of the machine to the other. The material is propelled forward by the screw as it rotates, while it is also pushed against the trough’s walls. Screw conveying is a precise method of material handling and is often used in the food industry, among others.
Design and Operation Comparison
Design Principles
The design of screw conveyors primarily relies on the auger’s diameter, pitch, and rotational speed to determine the throughput capacity. The conveyors operate horizontally or on an incline, with the material being contained within the trough. They are straightforward to assemble, and customizing them is not difficult.
The construction of a vibration feeder is more complex and commonly includes electrical components such as helical springs, heavy-duty bearings, vibration motors, and a vibration isolation system. These components work together to ensure that the vibration feeder operates effectively.
Operation Principles
Regarding the functionality of both conveyors, screw conveyors are highly efficient, especially for vertical transports and shorter distances, whereas vibratory conveyors can handle a higher capacity of materials. However, vibrating conveyors produce gentler handling actions to the material due to their low velocity and continuous, steady-state operation.
Characteristics Comparison
- Material Type: Both screw and vibratory conveyors are versatile machines that can transport a variety of materials, from powders and granules to larger particles. However, screw conveyors can convey viscous materials and materials that tend to “stick” to surfaces.
- Toxicity: Vibration conveyors can be an ideal solution for transporting toxic or hazardous materials. The conveyor design allows for enclosed transporting and the avoidance of material contact with workers. Screw conveyors are a popular choice for transporting food-grade or other sensitive materials as well as agricultural materials.
- Maintenance: Both conveyors require different maintenance requirements. Screw conveyors need frequent maintenance of joints, brushes, and bearings. Vibration conveyors require minimal energy consumption and can last for many years with maintenance of motor components.
Advantages and Disadvantages
Advantages of Vibratory Conveyors
- Gentle Product Handling: Vibratory conveyors exert minimal force on products, which reduces the risk of damage to fragile products.
- Low Energy Consumption: Vibration conveyors use less energy, making them more cost-effective than screw conveyors.
- Durable Feeder System: Vibration conveyors are robust and can withstand heavy loads and frequent use without breaking down.
Disadvantages of Vibratory Conveyors
Erosion and wear of components: The continuous vibration of the conveyor and the materials being conveyed can cause wear and tear on the conveyor components.
Advantages of Screw Conveyors
- High Capacity: Screw conveyors have a high capacity for transporting materials, enabling greater throughput.
- Multiple Inlet Ports: Screw conveyors are also capable of having multiple inlet ports, allowing for versatile applications.
- Low Ownership Cost: Screw conveyors require less maintenance and operating costs than other transport options.
Disadvantages of Screw Conveyors
Low Gentle Action on Materials: Screw conveying may have an abrasive effect on fragile materials transported. Due to the high velocity of the material interacting with the machine’s surface while moving through the machine.
Summary
Both vibratory conveyors and screw conveyors are effective in transporting bulk materials. However, each has unique design and operating principles, characteristics, and benefits. When choosing between a vibrating conveyor and a screw conveyor, you must consider the type of material you’ll be conveying, the distance over which you’ll be moving the material, and the operating environment. Throughputs and transport velocities are also critical considerations. Understanding the specific application and weighing the pros and cons of each solution is necessary to choose the right conveying system.
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