Look at almost any advance in parcel distribution center performance and you�ll find that lift trucks are integral to it. Over the years, lift truck technology has enabled space-saving concepts like narrow aisles and taller racks. Truck enhancements � faster speeds, greater capacities, higher reach, increased efficiency drive systems, control automation and ergonomic designs � have helped operators work more efficiently and have progressively reduced per-case handling costs.
Intelligent truck designs have even helped simplify interaction between operators, pallet loads and the warehouse management systems that handle the flow of information on which modern distribution centers depend. Recent innovations like AC drive and innovations on the near-term horizon � notably fuel cell technology and radio frequency identification (RFID) � will enable new leaps forward in lift trucks and their roles in warehousing productivity.
Driving Improvement
While distribution centers have changed greatly in the past half-century, owners� basic objectives have not. Speed, efficiency and accuracy continue to drive business success. With product purchase and selling prices essentially locked in under the realities of the marketplace, profit margin depends more than ever on driving down operating costs within the distribution chain. Lift trucks and their operators are central to such efforts.
The path toward today�s lift truck designs began in the mid-1940s with the invention of the four-way pallet, which became the industry standard and dramatically changed how shippers and receivers handled loads. As distribution centers sought to optimize use of floor space, the most obvious step was to build taller racks. Traditional counterbalance forklifts, which carry loads outside the vehicle structure, become more unstable when operating at higher heights. The higher the lift, the more counterbalancing required and so the bigger the truck.
The first major lift truck innovation was the straddle truck. Designed without a counterbalancing chassis, it handled pallets within the vehicle envelope and so could lift loads higher while retaining stability. This innovation allowed the trucks to be smaller, reducing aisle width requirements. The first straddle trucks, introduced in 1951, enabled aisles as narrow as 72� (versus the previous standard of 120� to 144�) and started the narrow-aisle revolution.
Stream of Innovations
The straddle truck started a series of dramatic lift truck innovations. As the demand for narrow-aisle vehicles increased, manufacturers responded with more compact, higher-reaching trucks, including designs for specialized applications. Major milestones included:
� Reach trucks � Introduced in 1954, these trucks overcame some limitations of straddle trucks and overtook the straddle truck as the truck of choice. Reach trucks easily handled pallets of variable widths and enabled more narrowing of aisles.
� Side-loading trucks � These trucks fit special applications where long, bulky materials must traverse narrow aisles. They offer multi-directional travel with heavy-duty capacities and stacking capability � from 2,000 to 10,000 pounds up to 30-feet-high.
� Guided order pickers � Operators on these units rise with the load to pick items from racks. Wire or rail guidance frees operators from steering in narrow aisles, enables higher travel speeds while elevating to the next location and speeds aisle transfers.
� Deep reach trucks � Created to maximize cube utilization, these units are designed to reach into racks to access loads.
� Very Narrow Aisle (VNA) turret trucks � Introduced in 1974, these operator-up trucks have the ability to rotate loads up to 180� to service both sides of an aisle. They can handle full pallets and case picking in aisles as narrow as 66�.
Growing Sophistication
In the 1980s, aided by an explosion in microprocessor power, manufacturers turned to innovations that would help owners get more performance and productivity from their lift truck designs:
AC drive � Arguably the most powerful innovation was AC drive technology. AC motors are more energy-efficient than DC motors, operating longer between battery charges. AC-powered trucks also experience less reduction in truck performance as the battery discharges. Operators benefit from improved acceleration and smoother, more precise control.
AC systems require less maintenance. AC controllers have no wearable parts, and because the motors have no brushes, there is no brush replacement nor residual carbon to clean from the compartment. Cooler-running AC motors also limit the wear and tear that results from heating of truck components.
Overall, operators using AC trucks commonly experience double-digit improvement in energy efficiency, increased truck uptime (truck utilization) due to fewer battery changes and significant maintenance cost reductions.
Intelligent speed control � This feature electronically selects the optimum maximum travel speed at every elevation based on the height of the forks, weight of the load, heading angle, travel direction, load handler position, status of guidance and operator speed request. The net result is travel speeds at elevation that are up to 30% higher between picks.
Coast control � With coast control, the operator can coast the truck between nearby pick locations, using a jog button or twist grips to move the truck from slot to slot. The coast control automatically disengages when the operator boards the truck and pushes the accelerator button. The system saves precious seconds, which can translate into a few more minutes of productive order picking time per operator per hour.
Advances to Come
As these and other innovations gain a wider acceptance in the marketplace, there are two technology breakthroughs that lie just over the horizon.
Radio frequency identification � RFID appears poised to become the method of choice for tracking materials and gathering and transmitting information throughout supply chains. It requires no physical contact between the pallet or case and the scanning device, which means lift truck operators do not have to dismount or otherwise expend effort and time to record the receipt, movement or placement of loads. RFID is currently being tested in a �living laboratory� at a Connect Logistics Services distribution warehouse in Edmonton, Alberta. This project involves Exel Logistics, IconNicholson and The Raymond Corporation.
In the distribution center, several types of lift trucks, pallet and carton storage locations, and dock doors have been equipped for RFID. Testing will measure the benefits of RFID for various applications and help determine how the technology can be deployed for optimal efficiency in distribution centers.
Hydrogen fuel cell technology � Fuel cells are still in their infancy, but may one day replace batteries and generate significant savings through longer run times, lower maintenance and the elimination of battery-charging infrastructure. They require only a refueling station where lift truck tanks are filled with hydrogen fuel. A major distribution center today may devote 5,000 to 50,000 square feet of space for battery charging and service. Upon conversion to fuel cells, that space can be filled with racking.
Fuel cells run cool and are extremely clean. Because they can be readily configured to fit the battery compartments of existing trucks, virtually all lift trucks in a given fleet can be retrofitted. All these advantages make a strong near-term financial case for fuel cells. Industry observers expect to see at least some distribution centers operating with fuel-cell forklifts by 2006 or early 2007.
More in the Future
As these breakthroughs unfold, manufacturers will continue to produce incremental improvements that enhance truck uptime and efficiency as well as operator comfort and productivity. Lift truck technology development is a constant process of creating and testing improvements that ultimately lower the user�s cost per pallet handled.
James B. Bennett III is Vice President of Sales and Dealer Development with The Raymond Corporation, a manufacturer of electric lift trucks for the warehousing and distribution industries, based in Greene, New York. For more info, visit www.raymondcorp.com.
