Giving manufacturers a lift
Everyone can use a lift once in a while. In fact, that was the thought behind the development of the lift truck in the first place. What began in the late 1800s as an evolution from hoists and cranes, lift trucks have long been an essential tool for manufacturers to move their materials and products through the various processes of manufacturing.
Today, manufacturers demand more from their lift trucks than ever before. As the movement to 24/7 operation has become reality for most, lift trucks have had to become more reliable. They’ve had to become more efficient because of philosophies like Lean manufacturing becoming prominent practice, as well as the ever-increasing need to cut costs and increase the bottom line. And with the dawning of global warming, environmental concerns have taken center stage for many, and truck designs have had to be modified to reduce their impact on the environment.
“As fuel, square footage, wages, labor and a list of all kinds of price increases attack the economy, (lift truck) manufacturers must respond to the changing times and design vehicles that will save time, money, space and improve safety,” said Peter Greenwood, vice president, sales for Airtrax, Inc., Blackwood, NJ.
Suppliers have responded by integrating technologies such as ac power and fuel cells. They have added electronics to provide end users with increasing amounts of knowledge about the trucks’ condition, and tools like fleet management systems.
|As manufacturers demand more from their lift truck fleets, suppliers are responding with new innovations to make trucks more capable and easier to maintain.|
AC power improves efficiency
“I think the big change over the last few years has been going to ac motors in the operation of lift trucks,” said John Colborn, marketing director for The Raymond Corporation, Greene, NY. “The byproduct of that is higher efficiency, better operational characteristics of the trucks, fewer components and fewer parts, so lower cost to operate.”
These characteristics can also lead to reductions in maintenance requirements and costs. Using ac simplifies the design of the motor and makes it easier to maintain, said Ken Biediger, product manager for Cat Lift Trucks, Houston.
“But the flipside of that is the controllers have to be more complex, and it’s taken a little while for the controller technology to catch up to the motors, at least in the forklift applications,” Biediger said. “The benefit with ac is they tend to be more efficient systems now, because the motor is simpler. But you really don’t get the full benefit out of the ac (motor) unless you’re working at higher voltages.”
High-voltage lift trucks are used in Europe, but have not caught on in North America because of a lack of infrastructure. That’s changing as end users discover the benefits of using higher-voltage trucks.
“Now we’re seeing 80 V coming in the counterbalanced lines,” said Greg Mason, general manager, products and training for Jungheinrich Lift Truck Corp., U.S.A., Richmond, VA. “Forty-eight volts is now being introduced in some of the Class II products, reach trucks, etc.”
Using higher voltage trucks reduces the current, making the truck more efficient, Mason said. Because the current is lower, the truck generates less heat. “If the overall truck is operating at a lower temperature, the lifetime of the electronic components in the truck will last much longer. So there are operational efficiencies, but there’s also lifetime cost efficiencies that are gained by having higher voltages.”
Fuel cells on their way
Fuel cell technology should have the same impact for manufacturers using lift trucks that its use in cars will have for consumers. How it will be used with lift trucks is, however, still an evolving issue.
|Convenient access to the instrument panel, steering wheel, hydraulic controls and dashboard provide more efficient troubleshooting and truck monitoring for the operator.|
“The topic of fuel cell integration into the lift truck market has received widespread publicity as of late,” said Martin Boyd, national product planning manager for Toyota Material Handling U.S.A., Irvine, CA. “The application of fuel cells in lift trucks will provide a number of benefits over their electric counterparts.”
Fuel cell technology is extremely environmentally-friendly and requires no hazardous fluids to be used, said Bobby Hopkins, a product specialist for Hyster Company, Greenville, NC. It offers an additional benefit that its electric counterparts cannot match. “They maintain full power until completely discharged, unlike dc batteries, where performance is reduced as the battery is discharged,” he said.
Technology issues must be resolved before fuel cells are mainstream lift truck components. One major challenge lies with counterbalanced trucks, where the traditional dc lead-acid battery acts as part of the counterweight.
“Once you pull that out and replace it with another fuel source, that fuel-cell is going to be lighter than any lead-acid battery. Significantly lighter,” Boyd said. “The challenges relate to how do you make up that weight? Do you put lead filler panels inside the battery compartment to make up the weight?
“There’s also a question about center of gravity,” Boyd continued. “When you have a lead-acid battery, it’s a pretty homogeneous load within the lift truck, and the center of gravity is essentially within that battery. But when you have a mechanism like a fuel-cell pack, the center-of-gravity may be closer to the front, closer to the back or closer to one side, and that changes the actual dynamics inside of a lift truck.”
“You have to be very careful to understand that a fuel-cell is not a direct replacement for a battery in terms of residual capacity on the truck,” added Mason. “Because if you change the center of gravity on the truck, you may be affecting the stability of the truck.”
The ‘brains’ of the truck
Electronic components such as vision systems, and technologies such as RFID and fleet management systems, make lift trucks ‘smart,’ and in turn, easier to use and maintain. They potentially add value to a manufacturer’s asset management system.
“There’s a lot of activity to assist the operators in their duties using technology,” Colborn said, including battery charge levels and the condition of wear parts.
“If there’s an issue with the truck, fault codes will be displayed,” Colborn said. “Mean-time to-identify-problems and mean-time-to-resolve problems is better.
“There’s been a lot of componentry taken out of the trucks, too. If I can draw an analogy with the computer industry, as computers have gotten a lot smaller and more powerful, that’s the kind of technology you see more and more in lift trucks. Doing more with less, because of the efficiency of the technology.”
Wireless technology makes trucks more powerful. As RFID technology matures and expands, new applications are being added to take advantage of its capabilities. Mason said some suppliers offer systems that can remotely limit a truck’s operating capabilities, depending on the truck’s programming and the specific area the truck is entering. Traits like speed and mast height can be limited based on tags placed on the truck and transponders located throughout a facility.
|Components are often added to give end users a‘lift.’ Vision systems (top) can assist operators when positioning forks or loads during pickup or drop-off. LCDs (bottom) provide real-time information for major operating parts, including the battery, brake, driver motor and pump motor, maximizing the uptime of the material handling fleet.|
“Another growing trend in wireless communications is wireless data acquisition,” Boyd said. “This is falling more in the area of fleet management or asset management. As a fleet manager, say I have a fleet of 100 trucks, and I want to make sure that these trucks are being optimized, and I’m getting the best cost of operation from my fleet of lift trucks. The best way to do that is to actually have data from the truck be downloaded into a datasheet or spreadsheet in which I could manipulate that data to make realistic and good evaluations and conclusions from.”
It’s critical that end users keep track of each truck in their fleet, Mason added. A lot of money can be saved or lost depending on how well this is accomplished.
“Basically it’s Fleet Management 101,” he said. “Keep track of the trucks that you have in your fleet, how often they’re down and how much it’s costing you to operate them on a monthly basis. It does take regular analysis to be sure that your older trucks are not costing you more than you think. A lot of people don’t know that. A lot of people don’t analyze that, and they lose a lot of money that way.”
As the demand placed on lift trucks has grown with expanded manufacturing capabilities in plants, lift truck suppliers have had to respond with modified designs. Through the use of new technologies, their trucks are becoming a more efficient, more invisible component of manufacturing with more capabilities, while being easier to monitor and maintain.
That’s quite a lift for end users.
Fuel cell benefits
Benefits of fuel cell technology for lift trucks, according to Toyota Material Handling’s Martin Boyd:
Comparable performance to internal combustion-powered lift trucks
Longer run-times before refueling
No battery charging rooms needed
Elimination of battery maintenance practices
No downtime required for battery recharge
Lower overall operating costs.