Lift Truck Basics
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Lift trucks are tools, and it's important to make sure you are using the right tool for the job. There is an enormous variety of configurations and options available for the modern lift truck going far beyond weight capacity and lift height. Doing a little homework up front to ensure you are choosing the best vehicles for your operation will result in optimal utilization of your space and labor while maintaining a high safety factor.
Before making a decision on the best vehicle for your operation you must have a thorough understanding of the properties of the materials you will be handling (loads), the methods you will use to store these materials and the methods you will use to ship and receive these materials. Once this is done you should familiarize yourself with the variety of vehicles and options available (see my Lift Truck Pics page and also spend some time at the various manufacturers sites listed on my Links Page). Below I have listed some of the different types of vehicles and their functionality.
Electric vehicles are designed for indoor use only. Their big advantages are the absence of fumes and their quiet operation. If you only intend to use your vehicles indoors, this is the way to go. In multi-shift operations you will need additional batteries and charging/transfer stations. In single shift operations, or, if the truck is not used 100% of the time, you can charge it during off hours. Note that the batteries and chargers for lift trucks are usually priced separately from the lift truck itself. You will also have choices of standard batteries or sealed maintenance-free types.
- AC or DC. Recently AC (alternating current) motors are being offered by several lift truck manufacturers, and no, this does not mean that you will be driving around with a really long extension cord. AC powered lift trucks run off of DC batteries and convert the DC power back to AC to power the motor. The advantages of AC motors include faster acceleration, higher efficiency, and lower maintenance costs.
- Regenerative braking. This technology recharges the batteries using the momentum of the lift truck when slowing down (braking). The frequent starting/stopping of lift trucks make them an excellent application for this technology. Similar to the technology used in hybrid automobiles.
- Fast charging. Fast charging provides a means to reduce or eliminate the need to change batteries on multi-shift operations. The idea here is to quickly recharge the batteries during breaks, lunches, and between shifts (frequently called opportunity charging). Though more expensive than conventional charging systems, fast charging is growing in popularity.
LP Liquid Propane.
Advantages of using LP include minimal fumes (however heavy use indoors requires adequate ventilation), the ability to use both indoors and outdoors, and the ability to quickly change LP tanks. Commonly used in indoor/outdoor operations such as lumber yards.
Gasoline or Diesel.
Outdoor use only. Heavily used in construction, scrap yards, etc.
The advantages of hydrogen fuel cell power include the ability to quickly refuel (similar to LP, Gas, or Diesel) avoiding the hassles and costs associated with battery changing/charging while providing the clean-air benefits of electric.
Fuel-cell powered lift trucks got a lot of attention some years back, but like most "next new things' you see hyped in the trade magazines, they don't seem to live up to the claims. I had included three links to big names in the industry at the time, but I just checked them and two of them are already dead. I would still consider this a technology to watch, but it didn't quite overtake the industry as was predicted.
Cushion Tires are solid tires generally with no tread pattern (though tread patterns are available) designed for use indoors on smooth solid surfaces.
Pneumatic tires require air and are designed for use outdoors on uneven and loose surfaces. Pneumatic tire trucks will also have higher ground clearance which raises the center of gravity thus reducing its rated lift capacity.
Lift Capacity and Lift Height.
You will need to know the maximum weight and dimensions of the loads you will be handling as well as the maximum fork height needed to stack or rack the loads in order to determine the capacity of the vehicle needed. The lift capacity of a truck is affected by lift height and load size. A larger size load moves the center of gravity of the vehicle/load combination reducing the lift capacity as does the height the load is being lifted. Attachments also affect the capacity of a truck. Every lift truck is required to have a placard showing the rated capacities. If there are any changes made to the truck — like adding an attachment — the placard must be replaced with one showing the revised capacities. Why spend so much time on capacity? Why not just play it safe and get a higher rated truck? The answer is size. Bigger is not necessarily better in warehousing. A higher capacity truck will be physically larger and require larger aisles than a lesser one.
Single, double, triple, quad (reflects the number of sections or stages the mast has) these are the types of masts available . In many circumstances you will not need to make a choice here since the lift height will dictate the type of mast you will get, however, in trucks with very high lift heights you may have an option. Going to a quad mast instead of a triple, rated at the same height, will give you a shorter mast in the lowered position, eliminating overhead clearance issues. However, the more sections to the mast the more play it will have when extended (the wobble factor).
You also need to consider Free Lift. Free lift describes the distance the forks can travel vertically before the mast starts to extend. Free lift is important if you need to stack or unstack loads within an area with a low ceiling, such as in trailers or containers.
Lift trucks are classified by the types of aisles they are designed to operate in. Wide Aisle and Narrow Aisle trucks are designed to turn in the aisle while Very Narrow Aisle trucks do not turn within the aisle. Read my article on Aisle Widths for more info.
- Wide Aisle. Standard forklifts fall into this category of trucks designed to work in aisles greater than 11' wide.
- Narrow Aisle (NA). Narrow aisle trucks operate in aisles of 8' to 10' and are generally stand up vehicles such as Reach Trucks.
- Very Narrow Aisle (VNA). Very narrow aisle trucks operate in aisles less than 6' and often use guidance systems (wire, rail, or optical) to travel within the aisles. Types of VNA trucks are Order Selectors, Swing Mast, and Turret Trucks.
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The standard forklift, also known as a counterbalanced sit-down lift truck, is the vehicle most people think of when they think Lift truck or Forklift. It is available with any of the fuel types and tire types as well as numerous weight capacities, lift heights and attachment options.
The smaller 3000 lb to 4000 lb trucks are the workhorses of most warehouses. If you are running a small operation and will only have one truck, this is probably the vehicle for you. The standard forklift is a wide aisle truck which requires at least 11' aisles to turn in. The aisle width is determined by the size of the truck, the turn radius, and the size of the load. Available options and attachments include side shifts, fork shifts, hydraulic clamps, and slip sheet attachments, to name a few. The side shift is becoming standard equipment on many trucks (I wouldn't purchase one without it).
There are also counterbalanced stand-up lift trucks available. They can be handy in dock areas where workers are frequently getting on and off the truck, and can also maneuver in smaller spaces. They tend to be at the lighter end of weight capacities.
Standard forklifts are usually used for lift heights under 20 feet.
a.k.a. Stand-up reach, Straddle reach , Double-deep reach. The reach truck is a narrow aisle (8'-10') truck designed specifically for racked pallet storage. It consists of outriggers in front and telescoping forks that use a hydraulic scissors-type mechanism that allows you to pick up the load and retract it over the outriggers. This reduces the overall truck and load length, allowing you to turn in a narrower aisle. Double-deep reach trucks use an extended reach mechanism which allows you to store pallets two deep in specially designed double-deep rack. Reach trucks are designed for racking areas only and do not work for loading trucks or quickly moving loads over distances. Operator training on reach trucks tends to take longer than on other vehicles due to the complexity of the controls.
Reach trucks are available with lift heights up to 40 feet, however, I don't recommend using them over 30 feet as it becomes very difficult to place loads at that height and puts a lot of strain on the operator's neck and eyes.
Motorized pallet truck.
a.k.a. Walkie, Walkie-rider, Rider.. Motorized pallet trucks are the motorized version of the pallet jack. They come in "Walkie" versions or "Rider" versions. As you would expect the walkie is designed for the operator to walk along with the truck as they move loads, while the Rider has a small platform which the operator stands on. The riders work great for frequent moving of loads over extended distances within warehouses and manufacturing operations. They are fast and highly maneuverable. Minimal controls result in short learning curves for operators although precision turning takes a little practice. Since there is no operator safety cage, there are some safety concerns with these and I do not recommend them for transporting tall unstable loads. If you are looking for an inexpensive method for moving loads from point A to point B, a rider may the answer. If you are moving heavy loads short distances and are looking for an employee-friendly option to the pallet jack, check out a walkie.
a.k.a. Walkie Stacker, Walkie Straddle Stacker. Rider. Stackers are relatively inexpensive lift trucks that are operated by a person on foot. These aren't typically used in high-volume operations, but can be useful in smaller warehouses. The walkie straddle stacker can allow you to work in narrow aisles while on a budget. Stackers are generally used below about 16 ft but some models can higher.
a.k.a. Order picker. Designed specifically for manual handling of less-than-pallet-load quantities in racking. Man-up design has fixed forks attached to a platform which elevates the load and the operator to facilitate manual loading and unloading from racking. Order Selectors are very narrow aisles vehicles which operate in aisles of less than 6'. I also find order selectors very useful in cycle counting and physical inventories.
Order selectors are available in lift heights up to 40 feet however 20 to 30 foot models are more common.
Swing masts, Articulated trucks, Turret trucks, and other VNA pallet handling vehicles.
Swing mast, articulated, and turret trucks are very narrow aisle vehicles designed to work in aisles of roughly 6 to 7 feet'. A swing mast truck resembles a standard forklift with the exception that there is an additional function to swing the mast to a 90 degree angle (only one direction) to allow stocking pallets perpendicular to direction of the truck's travel. The swing operation can get a little wobbly at heights so you must make sure you have stable secure loads (check links page for link to Drexel Industries for more info on swing masts).
Articulated trucks have a pivot point behind the mast and front-wheel steering. This results in the mast turning with the front wheels. Major brand names of articulated trucks include Bendi, Aisle-Master, and Flexi
Most turret trucks are man-up vehicles similar to an order selector with the exception that rather than fixed forks the forks are mounted on an additional mast and carriage which operates as a turret turning 90 degrees in either direction facilitating picking and stocking on either side of the aisle. The man-up design makes it easier to handle loads in very tall racking (up to 40 feet).Man-down versions of turret trucks are also available. They are less expensive than the man-up versions and are better when rack heights are less than 30 feet. Very narrow aisle trucks are generally recommended to be used in conjunction with a guidance system (wire, rails, optical) within the aisles to increase safety and reduce property damage. Also, man-up turret trucks operating with tall racking require that the floor be perfectly flat and level to operate correctly (see links page for links to Raymond , Crown, Hyster, and Yale for more info on Turrets). VNA pallet handling vehicles can be a little pricey, last time I checked, man-down vehicles were running $50k to $70k and man-up Turrets running around $100k. This does not include the guidance systems. In addition, these more complex pieces of equipment have more mechanical problems than standard lift trucks and you can subsequently expect more downtime and higher service costs. These cost can be easily offset in large warehouses by the space saved by going to 6' aisles.
For more information on going VNA, check out my article on Aisle Widths and my book Saving Warehouse Space. My book provided detailed information on how to calculate space savings.
See these lift trucks in action.
You should be able to find videos of just about everything covered here on Youtube or manufacturers' websites.
Attachments / Options
There is an enormous variety of attachments and options available for lift trucks. While most attachments are designed for use on standard lift trucks, some of them are also used on reach trucks and VNA trucks. It's important to note that OSHA requires that any attachment used must be approved for use by the specific lift truck manufacturer. This regulation pretty much forces you to go through the OEM dealer for the purchase and installation of the attachment. Also note that most attachments will change the capacity of the lift truck and a new placard should be placed on the truck showing the new specs. Below I will list some of the more common types of attachments.
- Sideshift. This is the most common attachment and, as I stated earlier, should be considered standard equipment. The sideshift device allows the fork carriage to slide left and right to allow more accurate placement of the load. Sideshifts will increase productivity and safety as well as reduce product damage by allowing the operator more flexibility in load placement.
- Fork positioner. Fork Positioners allow the operator to adjust the distance between the forks without getting off of the truck. Used primarily in high volume operations where there is a great variety of pallet and crate sizes handled.
- Fork pivot. Allows the forks and carriage to pivot (rotate). Used for transporting and dumping specially designed hoppers.
- Slip sheet attachment. Slip sheet attachments are used where slip sheets (a sheet of cardboard, paperboard, or plastic) are used rather than pallets. The slip sheet attachments has a push/pull mechanism that clamps onto the slip sheet and pulls the load onto a thin platform and then pushes the load off of the platform when the truck reaches the destination.
- Paper roll clamp. Designed specifically for the handling of large paper rolls, the paper roll clamp clamps around the roll and also allows for a full 360 degree rotation.
- Carton clamp. Operates like the paper roll clamp except the clamping surface is flat rather than circular.
- Drum handling attachments. There are a lot of different designs for attachment used to handle 55 gallon drums. Some are smaller versions of a paper roll clamp while others may engage the upper rim of the drum, or the lower rings. Some drum attachments are capable of picking up multiple drums at the same time.
- Prongs. A Prong is a specialized rod type attachment used for picking up rolls of materials such as carpet rolls, wire and cable spools, and rolled steel, by inserting the prong into the center of the spool.
- Fork extensions. Fork extensions slide over the existing forks on the truck to allow you to pick up longer loads.
- Height selector. A height selector is an option that allows you to preset certain fork heights to correspond with rack levels. This option is most commonly used on reach trucks working at heights above 20 ft.
- Tilt control. Tilt control allows you to preset fork tilt angles.
There are many safety features that are common to specific types of trucks such as seat belts on sit-down vehicles and dead-man pedals on most stand-up vehicles. In addition, some manufacturers are offering additional features such as speed controls that reduce speed based on load height and steering angle. Read my articles on Lift Truck Safety and Loading Dock Safety for additional safety info.
Service and Support.
An incredibly important part of lift truck selection is making sure you will have access to high levels of service and support. There seem to be new players in the lift truck market every year and while they may offer a nice truck design at a nice price, if they don't have the a local/regional service and support infrastructure, you should be prepared for significant aggravation when the truck goes down (all lift trucks go down at some point). Ideally, you want a local dealer/repair shop with a good supply of parts for the specific make and model you are purchasing. Visit the dealership (or repair shop) and take a look at his parts room just to try to get some idea of how many parts they stock and ask them "if they don't have the part, where will it come from?". Hopefully the answer is a nearby (not necessarily local) regional distribution facility. Also, try to get some idea as to how many of that specific model are currently in use in your area. This is especially important for specialty trucks (such as turrets). If there are only a handful of these trucks in use in their service area you should assume they are not stocking many (if any) parts for them and probably have very little experience servicing them.
It's also helpful if there is more than one business in your area that can service your lift truck. This tends to get you better service and pricing.
Also important is seeing if they have rentals available that have similar capabilities of the vehicle you are buying. Again, this is very important for specialty vehicles such as turrets especially if you are only running one or two of these vehicles in your operation.
New versus Used.
The selection of used over new is most beneficial in low use operations where you are putting very little wear and tear on the vehicle. In higher use operations, you very well may find that buying used costs more due to significant maintenance/repair costs that will be incurred. Be aware that there is "used" and there is "junk". Don't by junk. Used does not necessarily mean old. High-volume operations will purchase new trucks trade and them in every few years, these make for good used purchases because they are still considered current models and will therefore have greater access to parts and service. Safety is also a consideration since older models will not have the same safety functionality as newer models. I'm amazed to still see old counterbalanced forklifts still operating without safety cages (these trucks have to be 40 years old). Not only are these trucks unsafe, they are usually not very productive and extremely expensive to repair. I frequently see this in old manufacturing facilities that just can't get themselves to part with their old equipment.
Working with Dealer Reps.
Dealer reps can be a great source of information and will assist in determining the appropriate vehicles, however, keep in mind that truck types can vary significantly from manufacturer to manufacturer (especially on specialty equipment). Obviously the dealer rep will steer you towards something in his line regardless if there is a better alternative available elsewhere. When you have narrowed down the type of vehicle you are interested in, ask the rep to set up a visit to a similar operation using this type of vehicle and consider getting an onsite demo within your own facility. If you are still unsure I suggest renting one for a couple of months (ask upfront if you can deduct a portion of the rental cost from the purchase price if you decide to buy).
This certainly does not cover all of the vehicles and options available as there are many other specialty trucks as well as hybrids of the previous listed vehicles. It does cover most of the more popular types of trucks being used today. Remember an educated decision is a better decision.
Visit my Lift Truck Pics Page for more info also read my article The Aisle Width Decision for more detailed information on narrow aisles, very narrow aisles, and the equipment that operates in them.
Go to Articles Page for more articles by Dave Piasecki.
© Copyright. Content on InventoryOps.com is copyright-protected and is not available for republication.
Dave Piasecki, is owner/operator of Inventory Operations Consulting LLC, a consulting firm providing services related to inventory management, material handling, and warehouse operations. He has over 25 years experience in operations management and can be reached through his website (https://www.inventoryops.com), where he maintains additional relevant information.