May 27 2014

I Stock 000007470039 Medium

By: Dan Labell

The speed and accuracy of warehouse operations are key factors in a company’s success. Automation stands as the single best way to improve accuracy - up to 99.9% - and increase throughput rates two to three times.

The marketplace offers many Automated Retrieval and Storage Systems (AS/RSs). The challenge is to identify the type of automation that best fits a company’s needs. Not every technology is right for every need. In fact, matching technology to function, operations and budget is an important prerequisite in optimizing technology use. Important considerations also include the number of stock keeping units (SKUs), batch sizes, operating and maintenance costs and available space.

A Case in Point: Conventional Single Deep or Satellite® Technology

Here is the first question Westfalia poses: Is it necessary to have direct access to each indi­vidual load? If yes, then either a conventional single-deep storage system or a single-deep storage system with Satellite® technology (called TSAT) is contemplated.

When evaluating the two possibilities, we look to throughput performance expectations and cost as the next tier of decision factors.

In the case of a classic single-deep storage system, the number of aisles defines the numbers of Storage/Retrieval Machines (S/RMs) needed. TSAT, however, relies on throughput levels to define the number of S/RMs. In other words, TSAT technology overcomes the limitations of a traditional single-deep system.

How? The S/RM running in the main aisle is Satellite® integrated and equipped with a telescopic fork. It can enter a storage aisle located perpendicular to the main aisle. Once the Satellite® is in position relative to the pallet, the forks are extended to access the load, retract back to the Satellite® and then return to the S/RM. Thus, a single-deep system using Satel­lite® technology can operate with one S/RM in as many aisles as necessary, reducing the total automated warehouse investment dramatically.

The conven­tional single-deep storage system usually has three to four stacker cranes operating in three or four storage aisles. Thus, it carries higher investment and operating costs. However, it also has higher throughput capabilities.

The single-deep storage system with Satellite® technology provides an inexpensive al­ternative, but performance capacity must be individually assessed and adjusted accordingly. TSAT typically yields the following results:

  • a 20%-30% reduction in cost
  • a 10% reduction in shipping errors
  • a 115% increases in throughput

Single-Deep or High-Density Storage

If direct access to all pallets is not an absolute necessity, a high-density warehouse with Satellite® technology is a viable option.

When larger lot quantities per SKU are being stored in a ware­house, the storage aisles typically are individually dimensioned and the unit loads are stored one behind the other (depending on batch size). This approach is a compact, cost-effective way to store goods, reducing investment and operating costs com­pared to the traditional single-deep storage system with multiple cranes.

Innovative Concepts

An optional feature Westfalia offers customers is dual management of a central storage block of products, using two S/RMs. Thus, pal­lets stored between two S/RM aisles can be served by the S/RM in either aisle. This technology offers a range of ad­vantages for the user, including redundancy.

Another innovation allows both S/RMs access to a cen­tral block, allowing users to implement a true First-In, First-Out (FIFO) product rotation strategy. Here, one S/RM is only used to store pallets, while the other S/RM retrieves them. Concurrently, each S/RM functions as a standard aisle storage system, maintaining the storage and retrieval of pallets from the blocks to the left and to the right of the central, FIFO area.

Westfalia customers have experienced ROIs of 40% to 140% with these systems.


These examples provide a glimpse into the possibilities available and the considerations involved. Each company’s needs can only be identified through an evaluation, which will yield different solution designs for different businesses.

Based on individual data and other considerations, Westfalia could recommend a flexible, single-deep storage configuration. Alternatively, the design may be a high-density system that minimizes the number of S/RMs needed, the build­ing size and implementation costs.

Whether your company seeks to enhance an existing AS/RS or bring a whole new system online, Westfalia will assure a fit with your unique operations and budget.

To learn more, download our whitepaper titled: "Why Automated Storage and Retrieval Systems are transforming warehouse operations across the Americas."

Click here to download