Sterling Anthony, CPP
Sure, all packaging professionals know that their palletized loads will be handled by forklift trucks; that's why the loads are palletized in the first place. Not all, however, know enough about forklifts to maximize the advantages and minimize the disadvantages of load-handling by that type of equipment. The following is advice to that effect.
Design stable loads
A load's weight, weight distribution, size, shape, and position on the pallet, plus how that load is secured onto the pallet, are main determinants of load stability. Stable loads permit safe and efficient handling by forklifts, with accompanying savings in operational costs. The importance of load stability is reflected in the availability of various software programs that design pallet patterns that interlock for good stability and use of cube. Robotic palletizing, because it increases load uniformity, can further improve load stability.
Regardless of whether a load has been computer designed or robot constructed, something that should be avoided to the extent practical is overhang. Although typically discussed in relation to its negative effects on stacking strength, overhang also can affect forklift handling. If, for example, the forklift operator sees that there is overhang, he might slow his approach so that the masts (the vertical parts) of the forks don't impact the overhang. This reduces productivity. It also results in less than a full insertion of the forks into the pallet, a condition less than optimal for safe, efficient handling. On the other hand, if the operator doesn't notice the overhang, he's likely to approach at his conventional speed and impact the masts against the overhang, possible results being damaged goods and/or a load that's pushed out of alignment.
Stretch-wrap is the most utilized means of securing a load to a pallet and care should be exercised such that the stretch-wrap does not extend so far down that it interferes with the insertion of the forks. Although forks can easily tear through the stretch-wrap, not all brands of stretch-wrap are formulated to prevent tears from propagating. Those that aren't will lose their holding power and yield an unstable load.
Know how to recognize damage caused by forklifts
On those occasions where a packaging professional has to inspect a damaged palletized load, it would be useful to be able to recognize when the culprit is a forklift. In addition to the (load-related) conditions already mentioned, a damaged pallet might indicate forklift abuse. Sometimes the indication is convicting, for example a gouge, particularly on a stringer-board or block. Other times, a stringer-board bent inward or a block knocked loose only points a finger. As for deck-boards, the outermost are the ones most likely to show damage caused by a forklift.
Recognition of damage and suspicion that it's been caused by a forklift is not enough. There's the determination to be made about whether the pallet was too weak or the handling too rough. An immediate factor to consider is the history with pallets of that particular specification: if poor, a sturdier pallet likely is the solution; however, if good, the pallet likely met with an overly forceful forklift.
Know some basics about forklifts
A forklift is weighted in the back and that's what helps counterbalance the weight of the load being lifted by the forks. Simple enough. What might not be as readily grasped is the so-called stability triangle that forms the truck's 3-point suspension. Two points of the triangle are formed by the two front wheels (the ends of the drive axle); the third is the pivot point on the rear (steering) axle, regardless of whether there are two rear wheels or just one. The truck's center of gravity (COG) is located within that triangle. When the truck lifts a load, the combined center of gravity (that of the truck and that of the load) must be inside the triangle, because if not, the loaded truck will tilt forward or sideways, depending on where outside the triangle the combined COG is located.
The relevance to the packaging professional is that not only the weight of the palletized load but also its COG affects the stability of forklift handling. The rated lifting capacity (stated on the data plate of the forklift) is given as a load weight (for example, 4,000 lbs.) at a load center distance (for example, 24 in.). Translated, it means that the truck has the capacity to lift a 4,000 lb. load with that load's COG being 24 in. (horizontal) from the truck's masts.
A related measure is load moment, which is the force acting to tilt the forklift truck, and therefore, should not be exceeded. It's calculated by multiplying load weight by load center distance. Using the preceding example, the load moment would be 4,000 lb. X 24 in = 96,000 inch-pounds.
Granted, many packaging professionals get by just fine without knowing such technicalities, but that's because of two facts. The first is that most loads are on the standard GMA (Grocery Manufacturers Association) 40in. X 48 in. pallet; therefore, theoretically, the maximum load center distance is 24 in. (half of 48 in.). Second is that most loads on those pallets are of a weight that, when multiplied by the load center distance, results in a load moment that's within the rated capacities of the typical forklifts roaming the plants and intermediary facilities (i.e. warehouses and distribution centers) of most supply-chains. As such, there's not a high instance of trucks neither being unable to lift loads nor tilting in the attempt.
Spend time on the floor
Packaging professionals should avail themselves of all opportunities to observe how their palletized loads are being treated during forklift operations. If the packaging function is decentralized and located at the manufacturing facility, packaging professionals routinely find themselves going to the packaging line to troubleshoot. While on the floor, why not take time to observe forklift operations? The same goes for a centralized packaging function, with professionals that travel to the company's various locations. Also, packaging professionals should take a look-see, wherever an occasion takes them to non-company locations within the supply-chain, wherein the company's loads are being handled.
It's also important to understand that a forklift operates in two modes: one is lifting/stacking/lowering; and, the other is traveling. There should be a distinct and smooth transition from one mode to the other. They shouldn't be attempted simultaneously, for example, raising a load while traveling to the location where it will be placed. When loads are light enough to be handled stacked, but the combined height obscures the operator's forward vision, the operator should drive the forklift in reverse, looking backward. What a packaging professional should least want to see are operators ramming the loads, setting them down roughly, or otherwise mishandling. In all, it's not just about the protection of the loads but of personnel in the vicinity, too.
Lastly, to those packaging professionals who need added incentives to be more attentive to forklift operations, consider such major trends as cross-docking, source-reduction, and sell-from-pallets, necessitating that loads be handled efficiently, despite less material protecting them, and still arrive at final destination in showroom condition.
Sterling Anthony is a consultant, specializing in the strategic use of marketing, logistics, and packaging. His contact information is: 100 Renaissance Center-176; Detroit, MI 48243; 313-531-1875; 313-531-1972; [email protected]; www.pkgconsultant.com
Design stable loads
A load's weight, weight distribution, size, shape, and position on the pallet, plus how that load is secured onto the pallet, are main determinants of load stability. Stable loads permit safe and efficient handling by forklifts, with accompanying savings in operational costs. The importance of load stability is reflected in the availability of various software programs that design pallet patterns that interlock for good stability and use of cube. Robotic palletizing, because it increases load uniformity, can further improve load stability.
Regardless of whether a load has been computer designed or robot constructed, something that should be avoided to the extent practical is overhang. Although typically discussed in relation to its negative effects on stacking strength, overhang also can affect forklift handling. If, for example, the forklift operator sees that there is overhang, he might slow his approach so that the masts (the vertical parts) of the forks don't impact the overhang. This reduces productivity. It also results in less than a full insertion of the forks into the pallet, a condition less than optimal for safe, efficient handling. On the other hand, if the operator doesn't notice the overhang, he's likely to approach at his conventional speed and impact the masts against the overhang, possible results being damaged goods and/or a load that's pushed out of alignment.
Stretch-wrap is the most utilized means of securing a load to a pallet and care should be exercised such that the stretch-wrap does not extend so far down that it interferes with the insertion of the forks. Although forks can easily tear through the stretch-wrap, not all brands of stretch-wrap are formulated to prevent tears from propagating. Those that aren't will lose their holding power and yield an unstable load.
Know how to recognize damage caused by forklifts
On those occasions where a packaging professional has to inspect a damaged palletized load, it would be useful to be able to recognize when the culprit is a forklift. In addition to the (load-related) conditions already mentioned, a damaged pallet might indicate forklift abuse. Sometimes the indication is convicting, for example a gouge, particularly on a stringer-board or block. Other times, a stringer-board bent inward or a block knocked loose only points a finger. As for deck-boards, the outermost are the ones most likely to show damage caused by a forklift.
Recognition of damage and suspicion that it's been caused by a forklift is not enough. There's the determination to be made about whether the pallet was too weak or the handling too rough. An immediate factor to consider is the history with pallets of that particular specification: if poor, a sturdier pallet likely is the solution; however, if good, the pallet likely met with an overly forceful forklift.
Know some basics about forklifts
A forklift is weighted in the back and that's what helps counterbalance the weight of the load being lifted by the forks. Simple enough. What might not be as readily grasped is the so-called stability triangle that forms the truck's 3-point suspension. Two points of the triangle are formed by the two front wheels (the ends of the drive axle); the third is the pivot point on the rear (steering) axle, regardless of whether there are two rear wheels or just one. The truck's center of gravity (COG) is located within that triangle. When the truck lifts a load, the combined center of gravity (that of the truck and that of the load) must be inside the triangle, because if not, the loaded truck will tilt forward or sideways, depending on where outside the triangle the combined COG is located.
The relevance to the packaging professional is that not only the weight of the palletized load but also its COG affects the stability of forklift handling. The rated lifting capacity (stated on the data plate of the forklift) is given as a load weight (for example, 4,000 lbs.) at a load center distance (for example, 24 in.). Translated, it means that the truck has the capacity to lift a 4,000 lb. load with that load's COG being 24 in. (horizontal) from the truck's masts.
A related measure is load moment, which is the force acting to tilt the forklift truck, and therefore, should not be exceeded. It's calculated by multiplying load weight by load center distance. Using the preceding example, the load moment would be 4,000 lb. X 24 in = 96,000 inch-pounds.
Granted, many packaging professionals get by just fine without knowing such technicalities, but that's because of two facts. The first is that most loads are on the standard GMA (Grocery Manufacturers Association) 40in. X 48 in. pallet; therefore, theoretically, the maximum load center distance is 24 in. (half of 48 in.). Second is that most loads on those pallets are of a weight that, when multiplied by the load center distance, results in a load moment that's within the rated capacities of the typical forklifts roaming the plants and intermediary facilities (i.e. warehouses and distribution centers) of most supply-chains. As such, there's not a high instance of trucks neither being unable to lift loads nor tilting in the attempt.
Spend time on the floor
Packaging professionals should avail themselves of all opportunities to observe how their palletized loads are being treated during forklift operations. If the packaging function is decentralized and located at the manufacturing facility, packaging professionals routinely find themselves going to the packaging line to troubleshoot. While on the floor, why not take time to observe forklift operations? The same goes for a centralized packaging function, with professionals that travel to the company's various locations. Also, packaging professionals should take a look-see, wherever an occasion takes them to non-company locations within the supply-chain, wherein the company's loads are being handled.
It's also important to understand that a forklift operates in two modes: one is lifting/stacking/lowering; and, the other is traveling. There should be a distinct and smooth transition from one mode to the other. They shouldn't be attempted simultaneously, for example, raising a load while traveling to the location where it will be placed. When loads are light enough to be handled stacked, but the combined height obscures the operator's forward vision, the operator should drive the forklift in reverse, looking backward. What a packaging professional should least want to see are operators ramming the loads, setting them down roughly, or otherwise mishandling. In all, it's not just about the protection of the loads but of personnel in the vicinity, too.
Lastly, to those packaging professionals who need added incentives to be more attentive to forklift operations, consider such major trends as cross-docking, source-reduction, and sell-from-pallets, necessitating that loads be handled efficiently, despite less material protecting them, and still arrive at final destination in showroom condition.
Sterling Anthony is a consultant, specializing in the strategic use of marketing, logistics, and packaging. His contact information is: 100 Renaissance Center-176; Detroit, MI 48243; 313-531-1875; 313-531-1972; [email protected]; www.pkgconsultant.com
