Forklift Design Reaches New Heights
The evolution of forklift design in the past 60 years has had a positive impact on overall building design and distribution productivity. The question of “when is high enough too high” is still being asked and the answer continues to be, not yet. The progression from almost exclusive use of the sit down counterbalanced truck to the use of a wide variety of vehicles that include Narrow Aisle Reach Trucks, Order Selectors, Very Narrow Aisle (VNA) Turret Trucks, as well as the use of automated storage and retrieval system (AS/RS) solutions, has reduced overall building footprints and increased throughput. This article focuses on the advancements in the trucks.
The Counterbalanced Forklift (CB) continues to be a mainstay in the distribution and logistics industry. If your distribution model involves a small SKU base, large pallet quantities per SKU and full-pallet shipments, then this is an ideal option. The properly sized CB in a full-pallet distribution environment is capable of being used for most of the major warehouse functions including inbound receipt, put-away, order fulfillment and outbound truck loading. Due to its overall size and lift height limits, this truck requires larger aisles and more square footage of building than other alternatives. If order fulfillment requires individual case selection or a significant amount of layer picking, then the CB is not the ideal choice.
The Narrow Aisle Reach Truck was introduced to the industry in the mid ‘50s and the immediate impact was to reduce aisle width, increase stacking heights and reduce the overall building footprint. The increased stacking height created new challenges for building architectural and fire protection designers, but these challenges were easily solved as buildings got taller. In the ‘80s, the 400-inch lift height was introduced. This revolutionary lift height initially created challenges to operator productivity, building design and operational safety and were addressed as follows:
- Architects and engineers developed creative designs for fire protection systems that minimized or eliminated the use of in-rack sprinkler systems, while also improving the overall fire protection systems to the satisfaction of insurance companies and code officials.
- Floor design improved to allow for flatness that enhanced the higher lift height requirements.
- Initial throughput suffered at these heights but was overcome due to the introduction of lift enhancements such as shelf height selectors, lasers and cameras, combined with enhanced operator ergonomics.
- In time, operators adjusted to the increased heights, and throughput returned to expected levels. As an example, when the industry attained a 33 percent increase in lift height from 300 to 400 inches, it would have been normal to see a reduction of 4.7 percent in retrieval/put-away cycles daily. However if the increased lift heights were accompanied by a reduction in travel time of 8 percent, then daily cycles would go back up to the 300-inch lift heights. This allowed greater density without increasing building footprint.
Operations with high throughput case selection requirements with more SKUs were able to gain an overall increase in productivity due to the reduced footprint of the selection path. This increase netted a gain on overall facility throughput.
As SKU bases continued to grow for certain retail distributors, operators were looking for additional technology. To further reduce their case pick selection path and enhance productivity, Turret Trucks and Order Selectors came on the scene in the ‘60s and ‘70s. Today, the Turret Truck has lift heights to more than 600 inches, allowing for additional reduction in building footprint and the overall length of the case selection pick path, as well as consolidation of the slow movers. Issues associated with these taller buildings had already been addressed with the construction of 75 to 100 inch high AS/RS buildings. While in most cases the Turret Truck has not been as productive as a Reach Truck, by consolidating the right mix of slow movers to a single area of the building, the productivity gains from the reduction of the case selection pick path increased overall throughput.
The next generation of Reach Trucks is being introduced with lift heights of more than 500 inches. Keeping in mind lift truck enhancements, one can expect that operators and building designers will meet the challenges associated with these new heights without sacrificing productivity. This is based on the following:
- In the last 50 years, reach heights have grown to more than 500 inches, with significant gains on total throughput productivity
- Building designers have found new and improved ways to address fire protection issues that satisfy regulations
- Operators continue to adjust to new technologies, and their voices are heard by manufacturers for better ergonomics and productivity
So in the conventional world of lift trucks and high buildings, it appears that we continue to reach new heights.