Lift Truck Tips: A narrower margin of error

Especially in cold storage environments, narrow aisle configurations are common ways to increase storage density and reduce the price per cubic foot. Depending on the pressure to optimize space and factors like SKU proliferation, some might opt for the full very narrow aisle (VNA) approach, which is generally more expensive and involved than conventional narrow aisle installations.

While narrow aisle retrofits of existing facilities are possible, the transition is usually achieved during a new building project. But whether a new facility houses standard wide aisles with sit-down counterbalanced forklifts, narrow aisles with reach trucks, or VNA with turret trucks and order pickers, vertical space is always preferable to more square footage.

“A customer that does not use the entire cube of a new facility is living with wasted space,” says Perry Ardito, general manager of Jungheinrich’s warehouse products group for Mitsubishi Caterpillar Forklift America. “In support of customer demands, they’re seeing an increase in SKUs and are handling more or different inventory. These operations are soon looking for more space.”

An existing building might achieve as much as a 30% gain in storage density with a narrow aisle configuration, but Ardito recommends awareness of other restrictions that might impact the optimum use of a racking system. Building columns or variations in vertical height can dampen a return on investment (ROI), Ardito says, and is often less appealing than a taller building with taller lift trucks.

Not long ago, Ardito says, 360 inches was considered the maximum practical height for a narrow aisle facility. In recent years, narrow lift trucks went up to 400 inches, and the newest top out at 450 inches. But handling products above that height does require significantly increased care, and it can create some productivity losses. Modern narrow aisle lift trucks are easing the operator’s job with an assortment of intelligent features. Cameras and laser pointers help ensure fork positioning at height, while rack height selectors enable the mast to raise to the right row at the push of a button, letting the operator guide the forks the rest of the way.

Slotting becomes very important in tall systems, Ardito says, to make fast movers more accessible and keep slow movers up top. “A customer’s current system might allow any product to be put anywhere in storage, and that is not the most effective or safe methodology.”

Ardito says that even with hardware and software in place, racking should not be an afterthought. “There are not many racking companies whose products are all the same,” Ardito says. “Too many companies design a facility around the same racking system for multiple locations, where slots in the racking are often the same dimension. But whether for 1,000 or 10,000 SKUs, those SKUs should impact the design of a racking and storage system.”

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