Narrow-Aisle Form Follows Lift Truck Function

The ability to make right-angle fork turns makes both reach and turret trucks suitable for pallet-load handling within the racks. Wire- or rail-guided VNA turret trucks can lift operators as well as loads, so they can also be used for order selection. However, neither truck can move loads directly out of trailers and transport them from dock to rack.

Warren Cornil, president of Dallas-based Narrow Aisle Inc., says his company's Flexi truck doesn't have that limitation. The Flexi does not need guiderails, yet it can operate in aisles as narrow as three feet plus the depth of the pallet (usually four feet). “The Flexi will go into a trailer, allowing it to move product from trailer to rack,” Cornil says. “This eliminates the need for a reach truck and allows racking to be placed in the staging area.”

The Bendi lift truck from Marysville, Kan.-based Landoll Corp. also has this ability and is said to be able to maneuver in six-foot-wide aisles. But Cornil says the Flexi is different because it has front-wheel drive, which limits slip and reduces drive-motor maintenance.

Another factor that can influence narrow-aisle truck selection is operating environment. For example, the reach trucks in facilities owned by Phoenix-based Mesa Cold Storage, a 3PL specializing in temperature-controlled warehousing, must operate dependably in Arctic-like conditions.

“Mesa's frozen-grocery operation was demanding because of fluctuations in temperature,” says Pat McCutcheon, branch manager for H&E Equipment Services, the dealer that provided Mesa's lift trucks. Mesa selected Yale NDR035-EA reach trucks because of their reach capabilities — up to 400 inches — and their ability to operate at maximum speed and capacity in demanding conditions.

Recent Advancements

More trucks for narrow-aisle applications are being equipped with AC power, and new models offer greater travel and lift speeds, diagnostic and fleet management technology integrated into the truck as well as traction control, rack-height select and entry bar safety switches, according to Crown's Schwieterman. “As space continues to become a premium for distribution centers, we're seeing an increased need for lift trucks that reach higher while carrying greater capacities than in the past,” she adds.

Hyster's ZR AC-powered reach truck is available in single-reach and double-reach versions. The ZR has four programmable vehicle modes for speed, acceleration, deceleration and hydraulic ramping, according to Hyster, as well as regenerative lowering to minimize battery drain.

Introduced in September 2008, TMHU's 8-Series AC-powered reach truck features a self-adjusting electric disc brake with regenerative braking. The 8-Series also has a torque control system that helps prevent traction loss during acceleration and switch-back operation, according to TMHU.

Crown says its new 5700 reach truck has “the industry's first traction control system.” The OnTrac anti-slip traction control feature uses the integrated Crown Access 1 2 3 control system to analyze grip by comparing the truck's speed with the number of revolutions per minute on the drive tire. The system reduces tire spin during acceleration and prevents wheel lockup during braking. According to Crown, this feature decreases tire wear, increases efficiency, reduces the risk of accidents and improves operator confidence in slick conditions, such as those found in refrigerated or freezer applications. Available with AC-powered drive and hydraulic systems, the 5700 also offers one-touch rack-height select as an add-on feature. Rack-height select allows operators to stop the forks at a specific rack level by clicking a button. It senses when the truck is carrying a load and adjusts rack-entry height accordingly. In addition, a tilt-position-assist function levels the forks during pallet entry at upper rack levels.

Although equipment designs vary by lift truck manufacturer, one constant remains: Today's aisle-width conundrum is more about selecting the right material handling equipment than it is about just saving space.