Precast Modular Structures

The nation's leading manufacturer of modular concrete structures for corrections, telecommunications and education applications, discovers Wheelift's Omni-directional Transporters for indoor and outdoor use in their 200,000 sq. ft. manufacturing facility where they're building fully furnished precast modular rooms that weigh from 20 to 100 tons.

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Static build positions and tow motors no longer sufficed to serve the rapidly expanding disaster relief and communications markets which drove a wide variety of unique buildings to be built. As Henry Ford did decades ago, this manufacturing line moved to a progressive inline build process with tooled workstations and dedicated skilled trade's people..

Wheelift Transporters

The Wheelift® transporter sequentially indexes the precast modular rooms forward, one station at a time. The Transporter movements within each of the 5 assembly rows are automatically guided to within +/- 1" of center. Transporter moves external to the rows are by using a wireless pendant controller. The entire transportation system is a "lift-and-carry" indexing process. Picking up a room module from the manufacturing floor, depending on the room modules weight, consists of driving one or two transporters under the selected room module and carrying it to a "predetermined" position. The Transporters are designed to work singularly or in dual transporter "tandem" operations. Rooms in the 21' to 40' long weight range require two Transporters for movement.

When two Transporters are used, the operators position them together end-to-end, latches them together, and then switches the operator control to "Master/Slave mode" to operate multiple transporters with the single control. The "raise" switch is activated to raise both Transporters simultaneously, lifting the room module. The operator then selects the appropriate steer mode and begins moving the precast modular room.

CHALLENGE: Design an inline build production line process, requiring inside and outside precast room module access at all stations. Provide flexibility for line reconfiguration for dedicated lot runs and for unknown future production line arrangements.

SOLUTION: Provide two identical Omni-directional transporters for movement of in-process concrete room modules throughout the manufacturing floor areas consisting of fivebuild rows, each with eight tooling specific build positions, providing capacity for 40 unique build stations of modular concrete structures.

BENEFITS:

• Allowed a cost effective inline build process
• Provided flexibility for product size, product routing strategies, line configuration, line balancing, and labor staffing
• Protected for future growth trends

Process-driven features include a flat deck at 18.5" for product access from any direction, 3% slope capability, 6" vertical travel for self-loading and surface compliance, weatherproofing for travel to outdoor storage positions, umbilical cord power backup cable, wireless control, and fire suppression.

Flexible Modular Wheelift Chassis

The Modular Wheelift Chassis provides a degree of flexibility not attainable through other technologies. Wheelift Transporters and AGVs enable manufacturing flexibility with configurable work processes facilitating new design freedoms benefiting worldwide niche markets.

Wheelift Transporters and AGVs are manufactured in Iowa and are custom engineered to application specific requirements. Chassis and fixtures are available with load capacities to 500+ tons and deck heights as low as 18.5". Power options include diesel, LP gas, battery, or umbilical cord. Computerized all electric omni-directional drives are standard with individual axle ratings of 15, 20, or 30-ton.

SUMMATION: Providing flexibility to assembly processes, particularly for precast modular concrete structures can add a new dimension to a plant's profitability and throughput.