Tree of Life

Systems Integrator: Conveyors & Drives, Inc. (Atlanta, GA)

Keeping on the Growth Curve

New Conveyor System, coupled with advanced technology, helps Tree of Life keep pace with growing demand for its natural food products.

Since its founding in 1970, Tree of Life has enjoyed an unparalleled record of success. From its roots as a regional wholesaler of natural foods, Tree of Life has grown into the nation's leading marketer and distributor of natural and organic foods, nutritional and dietary supplements, and specialty foods. Today, the company has more than 6,000 employees and 15,000 retail customers.

Distribution excellence has always been a core component of the Tree of Life business philosophy. Strategically located across the United States, the company's distribution centers typically maintain in-stock positions of 95 percent on more than 30,000 SKUs—a performance few specialty foods distributors can match.

Nowhere is the emphasis on distribution excellence any more evident than at the company's Southeast Distribution Center in Elkton, FL. This modern 230,000 square-foot facility incorporates the latest in RF technology, an advanced Warehouse Management System, and sophisticated computer controls. The center also features an integrated network of Hytrol conveyor equipment that streamlines the flow of orders from the picking stations through to the loading docks.

"We had several key objectives in mind when we designed the Southeast Distribution Center," says Steve McCranie, senior vice president of distribution for Tree of Life. "We wanted to increase overall productivity and improve order turnaround time so that we could serve our customers better and faster. This distribution center is accomplishing those objectives-and the Hytrol conveyor system plays a big part in that."

The new distribution center, which went into operation in September 2001, represents a team effort. Conveyors & Drives Inc. of Atlanta installed the conveyor system and related controls. The company is an experienced systems integrator and distributor of Hytrol conveyor equipment. DCB & Co., an Atlanta-based consulting firm, designed the building and the materials handling system. DCB also served as overall project manager for the installation. These two companies worked hand-in-hand with Tree of Life's operations staff, led by McCranie and Corporate Engineer Brian Daniel.

An Integrated System

The Southeast Distribution Center incorporates a range of Hytrol conveyor and sortation equipment—all seamlessly integrated to achieve Tree of Life's throughput and productivity objectives. A key feature of the system is the more than 3,000 feet of EZ Logic conveyor in place. Hytrol's unique EZ Logic accumulating system effectively controls the accumulation and release of product from zone to zone.

The distribution center employs a wave picking approach. The order-flow process begins at the DC's two main order-picking areas. One is full case, the other split case (which Tree of Life refers to as the "each pick" area). In the full-case section, which also serves as a replenishment area, cases are picked onto takeaway transport conveyors that connect with two EZ Logic lines (190-ABEZ). These lines run in parallel along the outer wall of the building toward a sawtooth merge prior to entering the shipping area.

In the each-pick section, orders are picked from cases on gravity flow racks and placed into shipping cartons or totes. Horizontal belt sorters (SC model), located on each level of the three-tier picking module, efficiently divert the cartons to the proper pick stations until the orders are complete.

Completed orders from the each-pick area merge onto EZ Logic lines and head toward the sawtooth merge. En route, some are diverted to a quality control spur. Prior to entering the sawtooth merge, the cartons pass through strapping machines.

Dairy and other temperature-sensitive products are picked in a separate area adjacent to the three-tier picking module. These orders move up an incline belt conveyor to a recirculation line where they join the other cartons. Gapper belts regulate the flow of all orders from the main picking lines and the recirculation conveyor through the sawtooth merge. At present, the merge is handling an average of 65 cartons a minute. It is engineered to accommodate as many as 90 cartons a minute.

Orders emerge from the sawtooth merge onto a single EZ Logic line. The cartons then move through a servo-gap induction system, which sets the proper spacing for them to pass through a scan tunnel and toward the ProSort sorter. This high-speed sortation system diverts the cartons down one of 12 lines. These include the main lines for truck shipments and a separate line reserved for UPS. There's also a line designated for wave control as well as three lines used to replenish product.

At the shipping lines, cartons are diverted onto a small segment of gravity skatewheel that leads to a powered decline belt conveyor. This configuration was specified over the more common all-gravity option for an important reason: Tree of Life places a premium on keeping all orders damage free during the shipping process.

Technology plays a key role in the smooth operation. Manhattan Associates' advanced WMS, PkMS®, sets inventory and allocation rules for each product. It determines what items will be picked and where, which will be sent to QC, how orders will be diverted, and so on. That information is communicated to the computer controls, provided by Pyramid Controls. The control system then interacts with the conveyor system, which executes the orders. "The computer controls, coupled with the conveyor system, help us create a streamlined order flow and more effectively manage the wave picking process," notes Daniel.
Productivity and Reliability

Tree of Life has been pleased with the performance of the Southeast DC to date. Management reports that productivity levels continue to improve as they become increasingly familiar with the system. Overall reliability of the conveyor operation—a critical capability for anyone competing in the food distribution industry—has met expectations as well.

Thanks to the advanced technology in place, the new system also has given Tree of Life greater visibility over the entire order-flow process. Operators at the DC can spot potential congestion problems anywhere in the facility and take preventive action.

One other important aspect of the new operation bears mention—the installation experience. Corporate Engineer Daniel explains: "For a company like ours, the timeliness of the installation is all important. When we set a date, we expect that date to be met because delays in one DC can affect the entire operation. Everyone involved in this installation lived up to that commitment."

The Tree of Life Distribution Center

Product flows smoothly and efficiently through the 230,000 square-foot DC. Order processing begins in the full-case picking section (which also serves as a replenishment area) and in the "each pick" section. In the three-tier each pick section, SC sorters divert the cartons to the appropriate pick stations until the order is complete. Cartons move out of the picking areas on powered conveyor with the EZ Logic accumulating feature. Some are diverted to QC for quality check. All cartons from the main picking areas proceed toward a sawtooth merge where they are joined by orders from dairy, which move on the recirculation line. The cartons move through the sawtooth merge, go through a scanning tunnel, and then move onto the ProSort sortation line. The ProSort diverts the completed orders down one of the shipping lines or down lines reserved for replenishment or future wave management.

Company:  Tree of Life Inc.
Facility:  Southeast Distribution Center
Location:  Elkton, FL
Size:  230,000 square feet
Employees:  100
Key Personnel: Corporate Engineer Brian, Daniel, Senior V.P. Distribution Steve McCranie
Product Handled: Natural food products
Throughput:  60-65 cases/minute (capacity 90 cases/minute)
Types of conveyors:  Horizontal power (ACC and ACZ models), EZ Logic (ABEZ), gapper belt, sorters (SC and Pro-Sort), sawtooth merge, incline belt (RBI), gravity.
Project Management: DCB & Co., Atlanta, GA
WMS: PkMS, Manhattan Associates
Controls: Pyramid Controls, Inc.
Conveyor Supplier:  Hytrol Conveyor Inc., Jonesboro AR
Systems Integrator:  Conveyors & Drives, Inc., Atlanta, GA