One of the ways a vertical storage and retrieval system helps meet Lean Manufacturing initiatives is through the improved space utilization they offer by virtue of their vertical design.

By Ed Romaine, Remstar International, Inc., Westbrook, ME Conventional rack, shelving and drawer systems used in electronic component manufacturing facilities are a "less than lean" method of storing these small, sensitive items. Locating and retrieving electronic components stored in these traditional systems wastes time, floor space, increases production time and costs, and it can expose sensitive components to damage.

The focus of Lean Manufacturing initiatives is to eliminate waste that occurs as a normal part of manufacturing operations, and to optimize production flow to improve overall efficiency by creating added value with less cost. Vertical automated storage and retrieval systems address these issues by providing optimum solutions to five critical concerns when considering storage options for electronic components: space utilization/location, employee productivity, potential for component damage, ergonomics and cost justification.

Saving Time, Space, MoneyOne of the ways a vertical storage and retrieval system helps meet Lean Manufacturing initiatives is through the improved space utilization they offer by virtue of their vertical design. Depending on the usable building interior heights, up to 85 percent of a conventional storage system's occupied floor space can be recovered. Storing electronic components and other sensitive items at point-of-use also reduces unnecessary handling common with central storage. The reduction of wait time is another key consideration in Lean Manufacturing. Typically, an employee's walk and search time is reversed from that of conventional systems to 70 percent item retrieval and only 30 percent dwell time. In some operations, productivity can increase by more than 400 percent as a result.

Since vertical systems can be equipped with many variations of carrier and tray configurations, data is used to design the application directly to the need. For the storage of electronic components, sensitivity and location are primary considerations. When defining system requirements, component information is calculated to determine shelf or tray sensitivity requirements and component relation to one another. Once this data has been determined and grouped, it can be used to determine optimum storage. Consideration must also be given to the physical layout of the installation site. The clear height of the building interior will determine the height of the units and the total number of shelves or trays required in each unit. It is possible to estimate space savings in square feet and percentage using general formulas developed by automated storage and retrieval system manufacturers. For example, in a facility with a ceiling height of 40 feet, a vertical storage and retrieval system can eliminate up to 100 shelving sections with a resulting space savings of up to 929 square feet, or 91 percent. With a ceiling height of 30 feet, a vertical solution can eliminate 46 drawer-type cabinets for a space savings of 311 square feet, or 80 percent.

Controlling System OperationVertical storage and retrieval systems can be controlled using PC software or hardware controls. A system can be configured for standalone, single-user operation or multi-user network use. The operator simply enters the shelf number using the controls, and the shelf and its contents are delivered automatically.

Depending on the usable building interior heights, up to 85 percent of a conventional storage system's occupied floor space can be recovered. Storing electronic components and other sensitive items at point-of-use also reduces unnecessary handling common with central storage.

For functional effectiveness, transaction information must be communicated between the operator and the control system. The level of the system's sophistication will help determine how the information will be displayed to the operator. For example, in a strictly manual system, the operator decides all location transactions and enters, via keypad, the shelf or tray locations. This activity is followed by manual inventory adjustments. In a fully automated environment, all information requests from location selection, container type, inventory adjustment, activity analysis, and data transfers between the vertical system's software and the facility's host system, such as a facilities' MRP system. This can be accomplished transparently with no operator intervention.

The Right SystemIntegrated vertical storage and retrieval systems often have a return on investment (ROI) of less than 18 months. However, as with any major investment, a comparison of the costs of the new system vs. the old system must be considered. Sitting down with an installation specialist and putting the numbers into a standard ROI/IRR (Return On Investment/Internal Rate of Return) formula is one way to do this. Another is to log on to www.Remstar.com/roi and use a special ROI/IRR calculator that allows users to enter their data. The calculator computes dollar savings from reduced space requirements, cost savings from improved employee productivity, depreciation savings, and total annualized savings.

When considering the "leaning" of electronic component manufacturing operations, consider the use of vertical storage and retrieval systems to replace conventional shelving and drawer systems. After determining what the particular storage and retrieval requirements are, call in an expert to help specify a system.