Research Details

Frequently referred to as a rope and disk conveyor, Aero-Mechanical Conveyors (AMC) are said to be ideal for transporting material from 10 to 85 feet at rates of up to 120 tons per hour. Benefits of the AMCs are said to include low energy requirements, dust-free transport with minimal product degradation and virtually no separation of mixtures. Besides total batch transport, AMCs are said to offer totally contained, dust-free delivery and operation at any angle, including vertical at heights up to 85 feet without any loss in capacity. The system can be set up as a straight-line operation or in a variety of around-the-corner configurations. Aero-Mechanical Conveyors consist of several evenly placed polyurethane discs attached to a wire rope. The rope and disks travel in a continuous loop and move at high speed within parallel steel tubes. An air stream fluidizes and conveys the product.

For the last 14 years Excelso Coffee & Tea, based in Norcross, Georgia, has been using a ‘Spiroflow’ Aero-Mechanical Conveyor in its flavoured coffee production operation without replacement of any parts. Excelso is a custom provider of coffee and condiments to offices, vending machine outlets and for private label sales.

The Model PC3 Aero-Mechanical Conveyor (AMC) was manufactured and installed by us at Excelso’s production facility in 1994. Operating intermittently eight hours a day, five days a week, the AMC is used to convey flavoured coffee from a Vee-Ribbon blender to a storage hopper ready for packaging into coffee pouches or bags.

“When Excelso called and said they needed a replacement wire rope for their Aero-Mechanical System, it was the first time in 14 years. We were amazed at the life of the rope,” comments Mathias J. Lee, our VP- Sales “Normally, we expect these ropes to be replaced every five to seven years depending on the application. What’s equally phenomenal is the fact that no other replacement part has been required for the machine. This is as much a tribute to Excelso’s operation and care of their equipment as it is a testament to the robust construction of our Aero-Mechanical Conveyors.” Mathias Lee concludes.

Excelso Coffee & Tea roasts more than 2 million lbs of coffee a year which it then packages into hundreds of different blends. This equates to around 10,000 lbs, or 3 million cups, of coffee each working day. Through a sister company, Atlanta Coffee Time, Excelso supplies coffee in the Atlanta, Georgia metropolitan area to office workers and to vending machines strategically located throughout the city. Excelso is also in partnership with companies in over 35 states across the USA for whom coffee is custom packaged under their own brands. These companies use Excelso’s formula for success by distributing coffee to office workers and vending machine operators in their respective states.

Allan Shaw, Vice President of Excelso Coffee and Tea Company, recalls that Excelso initially selected the ‘Spiroflow’ AMC after a thorough analysis of the various suppliers and types of conveying systems. “We mainly selected Spiroflow because of their years of experience and record for excellent after sales support. We also needed a totally enclosed system that is dust free and wouldn’t alter the integrity of the flavoured coffee. The AMC seemed to be the perfect fit.”

The ‘Spiroflow’ Model PC3 Aero-Mechanical Conveyor plays a critical role at Excelso in conveying flavoured coffee from the Vee blender to a hopper for storage and eventual packaging. The AMC has 3 inch diameter conveying tubes. It is one of the most efficient methods of conveying materials such as coffee because of its gentle, dust-free and clean handling properties. Constructed of stainless steel to reduce flavour cross-contamination from the previous batch, the AMC can be washed with water or other cleaning solution through a valve sited at the top and a drain on the bottom. At Excelso, according to Shaw, the AMC is virtually self-cleaning. The Model PC3 AMC was specifically designed to meet Excelso’s exacting hygiene requirements.

One of the most significant features of the aero-mechanical conveying system is its ability to transfer total batches of material. They can operate at any angle between 0o and 90o without loss of capacity. At Excelso, the AMC is 30 feet long and operates at an angle of 45 degrees.

The Excelso coffee flavouring operation in detail
The Excelso coffee flavouring operation consists of the ‘Spiroflow’ AMC, a Vee-Ribbon Blender and the Storage Hopper. The Vee-Ribbon Blender is also made of stainless steel to eliminate any flavour contamination from the last batch and is tightly sealed. Its operation is completely computerized and automated.

The flavouring syrup is pumped gradually into the rotating blender in a fine, aerated mist that covers about two to three percent of the surface area. Once the syrup is added, the blender continues to tumble the flavoured coffee for several minutes to assure even dispersion of the flavouring.

Once this operation is completed, a manually operated hatch on the bottom of the blender is opened and the flavoured coffee is discharged into the AMC. The AMC conveys the coffee to a storage hopper. It is transferred to the hopper through a slide gate and a flexible hose.

Excelso operates the flavouring part of the plant in a single eight hour shift, five days a week. “We usually run 12 to 20 batches in a 4 to 5 hour run time,” confirms Shaw. “Each batch takes from 15 to 20 minutes. The rest of the time, we clean the blender and other equipment to purge it of any residual flavour. This is extremely important to maintain the precise flavour of each batch.”

How the AMC works
The AMC consists of a continuous loop wire rope assembly with evenly spaced polyurethane discs that move at high speed within parallel steel tubes. At each end, the rope assembly runs from one tube to another around specifically designed sprockets. One of these sprockets drives the rope and discs while the other sprocket provides tension to the rope. Tube clamps are used to support the conveyor. The action of the rope assembly travelling at high speed creates an air stream running at the same velocity. As the flavoured coffee is fed into the air stream, it is conveyed to the storage hopper where the beans are centrifugally ejected.

A significant feature of the Spiroflow Aero Mechanical Conveyor is its ability to convey material at any angle between 0o and 90o at heights up to 60 feet and more without loss of capacity. This enables the widest choice of system layout options to optimize available floor space. The system can be set up as a straight-line operation or in variety of around the corner ‘L’ or ‘Z’ shape configurations.

Frequently referred to as a “rope and disc conveyor,” ‘Spiroflow’ Aero-Mechanical Conveyors are ideal for transporting material up to 5/8 inch in diameter at rates of up to 120 tons /hour. User benefits include total transfer of ingredients, low energy requirements, dust-free transport with minimal product degradation and virtually no separation of mixtures.