Case Study: Transfer Carts in Automotive Manufacturing
Electro Kinetic Technologies recently completed a custom project for a global manufacturer of structural automotive components. With high tech processes such as hot-forming, roll-forming, hydro-forming, stamping, assembly and painting, this client’s portfolio includes light duty frames, space frames, suspension modules, body structures, safety systems, hinges, transmission modules and fuel tanks for passenger cars and light trucks as well as chassis frames, side rails and cross members for heavy trucks and buses.
Evaluation of Application
In the customer’s factory, they remove parts from a conveyor and transfer these parts to another location in the same facility using forklift trucks. The customer came to Electro Kinetic Technologies to help explore other options to move this material while reducing the reliance on forklifts. After reviewing several options, the team settled on using a motorized transfer cart to move the materials from the conveyor to the other area’s in the facility.
A key element that was added into the solution was an overhead crane that would move the parts off the conveyor and load them onto a removable rack located on the top deck of the transfer cart. The cart would then move to the unloading location where the entire rack would be removed using one forklift truck. This option completely eliminated the use of forklifts upstream while using only one at the downstream unloading point.
Other key elements that the customer wanted included in the transfer cart design:
- Move a maximum payload of 10,000 pounds.
- Ability for the operator to control the cart anywhere around the perimeter of the cart.
- Smooth and easily controlled positioning to insure proper loading and unloading of parts.
- An alarm for operator to identify when it was time to charge the on board batteries.
- Any debris located in the transfer route would not interfere with movement.
- Easy access of all control and electronic equipment for servicing, located in a protective enclosure.
In addition to engineering and manufacturing a custom transfer cart, the customer needed to have the production fast tracked so the transfer carts could be installed at their facility prior to the completion of other automation systems they were installing. To accomplish this fast pace timeframe, multiple design and operation teams worked in parallel to shrink the project schedule and still meet the customer’s goals.
The mechanical structure of the cart was designed out of heavy gauge steel welded together to provide a solid base for the 10,000 pound payload. Another feature of the cart design were shrouds located on all four wheels to clear away debris when the cart is moving in either direction. To allow the cart to be guided on a floor mounted rail system, industrial v-groove casters were used on two of the four wheels.
Utilizing motorized caster technology, the drive system was designed to provide sufficient torque to start and stop the load smoothly no matter what level of payload was loaded onto the cart. Integration of a wireless control system, allowed the operator to easily control the speed and direction of the transfer cart anywhere around the perimeter of the cart while maintaining a safe distance during loading, unloading and transfer. Because the project had multiple carts, each cart had its own pendant and a master pendant allowing the operator to control more than one cart from a single pendant control station.
Each cart included onboard maintenance free batteries and charger. An integral part of this battery management system, was a custom alarm to provide the operator with both a visual and audio warning when the batteries required recharging. All of the electronics and batteries were housed in a NEMA 4, IP66 rated enclosure with a removable cover designed into the top of the cart to provide easy access to the enclosure for maintenance.
After completing final inspection, each cart was put through a final test procedure to fully verify the carts compliance to the design specifications including a full load test on the rail system.
For more information on custom motorized solutions, and Electro Kinetic Technologies’ engineering services, visit our contact page and consult with one of our experts.