Material Handling Equipment: Conveyors and Elevators

Material handling is a crucial aspect of many industries, including agriculture, mining, manufacturing, and logistics. Conveyors and elevators are essential equipment used for the efficient movement of materials (such as grains, seeds, or bulk materials) within a facility. Below is an overview of conveyors and elevators, their principles, working mechanisms, and selection criteria.

Conveyors

Definition: A conveyor is a mechanical system used to transport materials or products from one place to another, typically over a fixed path. Conveyors are commonly used to move bulk materials or packages within industrial environments.

Types of Conveyors:

• Belt Conveyors: Flexible and used for transporting a wide variety of materials, including bulk materials and packaged goods.
• Roller Conveyors: Use rollers to move materials and are often used for handling heavy or flat-bottomed goods.
• Chain Conveyors: Use chains and are ideal for heavy-duty tasks or items that are difficult to move by belts.
• Screw Conveyors: Employ a rotating helical screw blade to move materials.
• Vibrating Conveyors: Materials are transported using vibrations that make the items move.

Principle and Working of Conveyors:

• Principle: The basic principle of a conveyor is to move materials in a continuous and automated manner from one point to another with minimal labor effort.
• Working: Conveyors work by moving materials along a system of pulleys, rollers, or chains, driven by motors. The material is transferred via a moving belt, rollers, or chain links, depending on the type of conveyor.
  • In a belt conveyor, for example, a belt is continuously driven by a motor-powered pulley.
  • In a roller conveyor, rollers are placed along a path, and materials are moved by gravity or powered rollers.

Advantages of Conveyors: Continuous movement of materials without manual labor. Efficient for long-distance transport. Can move heavy, bulky, or irregularly shaped materials. Reduces the risk of injury compared to manual handling.

Disadvantages of Conveyors: High initial installation and maintenance cost. Limited to fixed paths. Can be prone to wear and tear, especially for continuous operation.

Selection of Conveyors: When selecting a conveyor system, the following factors should be considered:

• Type of material: The shape, size, and weight of the material being handled.
• Distance: The distance over which the material needs to be transported.
• Conveyor capacity: The amount of material the conveyor can handle per hour.
• Space and layout: The available space for installation and the desired layout of the conveyor system.
• Environment: The operating conditions (temperature, humidity, dust, etc.), as some conveyors are more suitable for specific environments (e.g., wet or corrosive environments).

Elevators (Grain Elevators)

Definition: An elevator is a vertical transportation system used to lift bulk materials such as grains, seeds, or fertilizers from one level to another. Grain elevators are typically used in agriculture for moving grain to higher storage bins or silos.

Types of Elevators:

• Bucket Elevators: The most common type of elevator for handling bulk materials. They use a series of buckets attached to a chain or belt to lift the material.
• Grain Elevators: A specialized form of bucket elevator designed for lifting grains or other agricultural products.
• Continuous Elevators: These operate in a continuous manner, without pauses between operations.

Principle and Working of Elevators:

• Principle: The principle of an elevator is to raise materials vertically using buckets or other containers attached to a continuous loop system (chain or belt) which is powered by a motor.
• Working: In a bucket elevator, buckets are attached to an endless chain or belt, which moves vertically inside a casing. The material is scooped into the buckets at the base of the elevator, and the buckets travel upward, carrying the material to the desired height. Once at the top, the material is dumped into a chute or another container.
  • Chain or Belt: The type of mechanism (chain or belt) used depends on the material to be lifted, the distance, and the type of elevator.

Advantages of Elevators: Efficient vertical transport of materials, especially for bulk materials. Can handle a wide range of materials, including grains, powders, and pellets. Higher lifting capacity compared to conveyors for vertical transport. Minimal material spillage and dust during operation.

Disadvantages of Elevators: Require more space for vertical operation. High maintenance needs for moving parts (e.g., chains or belts). Can be subject to wear and tear from constant loading/unloading.

Selection of Elevators:

The selection of an elevator system is influenced by the following factors:

• Material Characteristics: The type (grain, powder, etc.), size, and weight of the material being lifted.
• Lift Height: The required vertical distance for lifting the material.
• Capacity: The required amount of material to be moved per hour.
• Speed: The speed at which the material needs to be lifted.
• Environment: Whether the elevator will be used in a dusty, corrosive, or wet environment.
• Energy Efficiency: Energy consumption of the elevator system, especially for high-capacity systems.

Comparison of Conveyors and Elevators: