Pneumatic conveyors (or air conveyors) are devices that use airflow to move items or media. There are many different types of products. Examples include vacuum conveyors, pneumatic tube conveyors, and air tables. Vacuum conveyors consist of a perforated belt, vacuum source, nozzles, filters, and tubing. Products are placed flat on the belt to create a seal. Pneumatic tube conveyors or air conveyors use low-pressure air to push or pull a short, closed cylinder through a pipe between origin and destination, usually only one way at a time. There are two basic types of pneumatic tube conveyors: dilute-phase pneumatic conveyors and carrier-system pneumatic conveyors. Air tables are air conveyors that use nozzles or a porous medium to control the flow of air to a perforated table. The air that flows between the moving load and the supporting surface reduces the coefficient of friction and allows operators to rotate and position heavy loads.

Performance Specifications

Performance specifications for pneumatic conveyors include maximum load, speed, volume of material transported, mass flow of material, and number of pieces per minute. Additional specifications vary by product type. For example, parameters for vacuum conveyors include hole-pattern and diameter, belt type, vacuum source and number of ports. Typically, the holes in a vacuum conveyor’s perforated belt are arranged in one or more rows. High-friction belts are designed to move rigid parts such as plastic caps, ceramic wafers, and glass bottles. Electrically conductive belts are designed to move paper, cardboard, and plastic film. Cylinder size is an important consideration for pneumatic tube conveyors. Parameters for air tables include pressure drop and air flow. Other types of air conveyors carry additional specifications.

Applications

There are many applications for air conveyors. Vacuum conveyors are used to move pellets and powders in painting, water purification, and product mixing applications. Some pneumatic tube conveyors are used to move invoices, documents, and drawings between buildings or within offices. Others are used to move plastic, metal, or ceramic powders and granules. Air tables are used in many different industries and applications. For example, self-propelling conveyors are often used in conjunction with panel saws, feed tables, cutting tables, and woodworking equipment. Specialized air conveyors that entrap and reduce dust are necessary for glass cutting applications.