WHEELIFT TRANSPORTERS

The new generations of Wheelift heavy load moving transporters are actually quite amazing.  These heavy move solution transporters are fully self-contained and typically have overall flat-top deck-heights of less than 19 inches.  As shown on the right, in a “headless” configuration and with their ultra low deck heights, they can enter and exit stand-supported machinery from ANY direction.  With up to eight inches of vertical travel, these transporters can lift and carry any machinery where support stands provide 20 inches or more of drive-through clearance under their frames.

Initially, Wheelift transporters were available only in hydraulically powered configurations with LP gas engines in raised engine compartment.  Wheelift now concentrates on building electrically driven* ultra-low profile, all-wheel drive, transporters powered by LP or diesel engine/generator systems with the option to also operate on shore power.  While battery operated systems have been the norm across industry for conventional lighter applications, the move to engine-generated power dramatically expands the operational parameters and system capacities for both in-door and outdoor operations. Click here to view a 6 min video clip.

For companies that build a wide range of very heavy product sizes, they are often best served by using two, three, or four transporters that operate in tandem.  Products being assembled are typically raised on support stands that provide 20 inches or more of “tunnel space” for transporter entry. If the products are physically large enough to require more than one transporter, the additional transporters will be driven under and be carefully positioned to be parallel to each other with the axles all aligned on matching centerlines.  Careful attention to alignment assures that whichever transporter that becomes the “Master” unit, it can easily control the exact wheel geometry of each of the tandem operating “slave” transporters. 

Current generations of Wheelift transporters are typically “headless”. That is to say, their engine/generator and all of the control machinery are housed below the 21 inch deck height. This unique arrangement allows an ultra-low overall transporter height. In the headless configuration, the transporters can enter or exit from under the load in any direction. The transporters typically have 8 or more inches of vertical lift capability to accommodate lift-and-carry operations, as well as provide the needed individual axle compliance to handle severe undulations and irregularities in the factory floors and yard surfaces. Ramps often need to be negotiated when moving in and out of manufacturing spaces. The amount of available lift determines the severity of ramp conditions that can be negotiated.

Electrically driven all-wheel drive Wheelift transporters can have six, ten  or more axle assemblies and every wheel is independently driven. The onboard SynchroSteer® PLC based computer handles the complexity of “differential” steering by controlling the individual motor speeds and direction that provide the vehicle’s fully omni-directional travel capabilities.

Each axle assembly under the transporters has wide-faced solid urethane tires on each end of laterally articulating axles. This arrangement allows the tires to load equally on sharply varying floor surface slopes and irregularities. Further, each axle has a vertical travel center column that provides fluid equalizing suspension across every axle in the system, as well as providing the lift for self-loading. The fluid lifting center column is the key to allowing independent on-center rotation of each axle for the transporter’s all-directional travel capability.

 

The omni-directional travel capability is inherent to the basic functionality of the Wheelift system. While depending on the application, a transporter carrying a 100-ton load may only need to drive straight or make relatively long radius turns, the fundamental basis of the Wheelift design mandates that each of the axle assemblies has the capability to rotate independently on center, which, in turn provides the capability for the transporter to move laterally, diagonally, rotate on-center, or make very sharp radius turns. The very important fluid equalizing suspension provides the ability to lift and lower; to both proportionally share the load across every tire in the system as well as have the ability to self-load by driving under a stand or pallet supported load. This capability allows transporters with heavy loads to travel over relatively thin and weak floor systems without the damage and difficulties caused by conventional wheel systems. For relatively light loads, equalizing suspension is less critical, but as the load increases, the need for full equalizing suspension increases dramatically.

The determination of when and where Wheelift transporters or AGVs can be justified is whether the desired load weights are too heavy or otherwise difficult for conventional equipment. After a careful evaluation of why conventional heavy trailers, overhead cranes, machinery moving “skates”, air bearings, or in-floor rail systems CAN NOT do the job, only then should the Wheelift solution be considered. When there are compelling reasons why conventional handling means will not work or are far too costly in terms of the man-hours being expended, then it becomes easy to justify the investment for Wheelift technology.  If price is more important than functionality, then the Wheelift technology may not be applicable to that application. Generally speaking, this multiaxle, heavy capacity, tandem operating, self-loading, transporter technology only applies to loads that have to move often and the requirements are too complex for conventional means and will not provide the type of maneuverability needed.

 

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TRADEMARKS

The following terms that are used through this website: Wheelift^®, Uniload^®, SynchroSteer^®, StackAxle^®, TrackAxle™ and OmniAxle^™ are all trademarks that are exclusively licensed to Doerfer Companies.