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With the advent of lean manufacturing and minimal inventories, racking isn't as prevalent as it once was. Gone are the days when drivers put a lot of miles on a forklift between cluttered racks and workstations. Yet racks still play a role. According to Jim Sterner, vice president of engineering at Winsted, Minn.-based SJF, it's more important than ever to integrate racks smartly. The below tips, he says, may point shops in the right direction.

The application, not space, dictates rack placement. Often, companies may place racks in an unoccupied area "rather than the area best suited for storage," Sterner explains. For instance, companies may put racks along open wall space instead of areas that allow strategic flow of materials to and between workstations. Sterner adds that close proximity to the point-of-use may not be the best solution, either. One company, for instance, stored parts for welding directly at and above workstations. It seemed logical, but in order to get to the material, welding machines and other equipment had to be moved.

Enter lean thinking. The company now stores material in another area. When needed, materials stored in racks away from the workstation are put into totes and then moved via automatic conveyor. "Now, those welders have very little material in front of them—just what they need," Sterner explains. "An automatic conveyor brings parts to them throughout the day, replenishing supply as needed."

Consider lift trucks and racks together. Many companies purchase racks and, to save money, use their existing lift trucks, Sterner says. Ceilings may be 25 feet, but forklifts may only go up 16 feet—so they use racks only 12 feet high. "Instead of selling that forklift and purchasing another that will go higher, companies waste that square footage of storage space they have above."

Lift trucks also determine aisle width. A company's existing forklift, perhaps made for outdoor use, may have a 14-foot turning radius, which requires more space between racks. An indoor lift truck could maneuver in a 9-foot aisle and, as a result, save floor space dramatically.

Lift-truck attachments should also enter the equation. A company needing four rows of racks does not necessarily need three aisles. Special attachments allow lift trucks to access two pallet depths, so four racks may only need one aisle, with racks two deep on each side. (Note, this technique may not work best for first-in-first-out handling.)

Inventory for one application need not be all in one place. In the spirit of lean, inventories should be reduced as much as possible. But if inventory can't be avoided, all of it need not be in one place. Shops can break that inventory down so that, say, only a few day's worth sits in one part of the floor while remaining parts are stocked in different racks elsewhere.

Sterner recalls one boat manufacturer that used the same standard shelving for a wide variety of material in one place, which resulted in some serious bottlenecks. To solve the problem, the company installed cantilevered rack in one area to handle raw material coming in; such racking offered denser storage and reduced time required to unload material from trucks.

The manufacturer then broke that inventory down to get a usable amount closer to the point of use. For example, rolling racks holding about 30 to 40 sheets of aluminum, placed by press brakes and shears, provided enough material for about three days of work, after which they were replenished. So instead of holding tons of sheet in one place, the company kept a manageable amount directly where workers needed it.

"Every manufacturing process has its own material-handling problems," Sterner concludes. But one common thread, he says, is that it doesn't pay to have clutter. In thinking lean, haphazard racking shouldn't overwhelm the shop floor with material. Instead, they can be set up to provide workers with the right amount of material just as they need it--no sooner and no later.