Automotive manufacturer Ford’s Silverton assembly plant, in Pretoria, has improved the automation of the Ford Ranger production line, following the installation of a conveyor belt and wax system, as well as further improvements to the underbody system of the production line, which were all completed in 2014.
Ford Manage the Change – the division responsible for introducing and implementing changes in the manufacturing environment – team manager Victoria Machete tells Engineering News that the automated system significantly assists operators in efficiently installing the various components on the vehicle using automated equipment to move components into their respective areas.
For example, wheels are rolled down the conveyor belt to the installation station where a hydraulic-powered bar lifts each wheel for the operator, who then rolls the wheel onto a platform that automatically aligns it to the wheel’s hub. The operator places the wheel onto the wheel hub and places lock nuts onto the wheel studs. The assembly line then moves the vehicle down to another station, where the nuts are tightened to the vehicle.
Components are placed onto the conveyor belt following selection by material handlers that use a pick-to-light (PTL) system linked to a vehicle specification broadcast (VSB) system, enabling material handlers to supply the correct part required for each vehicle specification within a specific time frame.
The PTL system uses the information from the VSB system, together with a lighting system, to indicate to material handlers which parts must be selected and placed onto the production line. A network of digital lights are installed on the storage area of every component and, when a particular part needs to be selected, the PTL system will switch on the relevant light, which remains engaged until the part has been selected.
Ford Silverton also employs a scan-to-fit (STF) system, which enables operators to scan each part. The part is then validated by the AIS to ensure that the components installed on the vehicle match the specifications.
The plant also employs an automated first-in, first-out (Fifo) system to ensure efficient stock rotation and prevent storage costs associated with holding stock for extended periods. “Our Fifo system ensures that the first components supplied are the first to be fitted onto vehicles on the assembly line,” Machete says.
Meanwhile, she tells Engineering News that one of the functions of the Manage the Change team is to implement an integrated online system, which enables the various workshop areas, including the body shop, paint shop and trim line, to use the Fifo and PTL system, and the Assembly Information System that is linked to the VBS.
“Owing to the integration of Ford systems, the change management team also ensures that all areas within the manufacturing area are ready for changes prior to implementation,” adds Machete.
She explains that the body shop’s improvements to its underbody automation system in 2014 ensure that it now has “no manual interventions”, except for manual support for maintenance. Most operations in the body shop use robotic systems to assemble the Ford Ranger body, adding that improvements to the vehicle’s underbody system have been ongoing since the vehicle’s launch in 2010.
Once completed, the body is sent to the paint shop where automated systems apply the paint and wax. The wax automation system allows for the vehicle body to be sprayed with a corrosion-resistant coating.
Following the completion of all paint shop processes, the body is sent to the trim line where all the various components, including electronics, seats, steering wheels and tyres, are installed.
Machete explains that quality verifications are also done during the assembly process.
“During vehicle assembly there are over 100 quality verifications and checking points, and more than 55 sign-off points to ensure that we produce our vehicles to Ford’s quality operating system standards,” Machete explains.
She adds that Ford vehicles undergo a range of tests, such as weather-resistance tests, to ensure that every Ranger meets the Ford group’s international standards.
Ford Silverton exports the Ranger to over 148 markets including South Africa.