Just as the tractors made by Case New Holland Inc. (CNH) have made the American farmer more productive, CNH needed to find some new manufacturing efficiencies of its own.

To begin, CNH integrated its manufacturing operations in Racine, Wisc., as it right-sized for a leaner market for farm tractors. CNH closed a 1.5 million square foot assembly building in Racine and moved those operations into a nearby 600,000 square foot facility that had built transmissions. The transmissions facility was expanded by 60,000 square feet with the addition of new docks, a paint system and a testing area. At the same time, CNH took a close look at its materials handling practices and equipment.

Continuously moving conveyor lines replaced the indexing lines of old. Specially-designed carts (Topper Industrial) transport transmissions and chassis between assembly stations. A new cab delivery system uses a monorail to deliver cabs just as they are needed to the assembly line. More familiar materials handling equipment, such as a power-and-free conveyor for the paint shop and in-floor tow-line conveyors, were brought in too, striking the right balance between flexibility and productivity.

What gets done in the new facility is different too. Cab and chassis assembly lines were introduced to the facility, where before only transmissions, axles and other key components had been produced. Some of the machining, paint and subassembly work that had also been previously done there is now outsourced to suppliers.

Although the plant now builds eight models of tractors under the Case and New Holland brands, the range of options available requires considerable differentiation tractor to tractor. That put a heavy emphasis on flexibility.

'With our dual-brand strategy, we have numerous components that differentiate them,' says Jason Martin, materials team leader. 'There is also a lot of optional content. Around 95% of product is unique by the time it comes off the line.'

Production is build-to-order within the facility, with transmissions manufactured first. These are built on carts moved along on in-floor rails. The carts are designed to handle the options available for each model with supports that flip up or down depending on the requirements. Steps are integrated into the carts to allow shorter workers to reach their assembly tasks more easily. Built-in fork channels additionally permit lift trucks to return emptied carts to the beginning of the assembly process. A few articulated trucks maneuver in the tight confines of the facility.

The cart is then pushed onto an in-floor tow conveyor for assembly of the chassis, which combines the transmissions, axles and engines. It is also the point where another clever cart solution is employed to resolve a problem that occurs during the addition of the front axle. When the axle is placed on the assembly, it changes the center of gravity, and the original transmission cart can no longer hold the load without tipping. One option was to transfer the load to another cart, but that would require additional handling steps. The solution chosen was to simply add a small connecting cart to the front of the load to support the front axle. This cart just rides along on the tow conveyor with the rest of the chassis line.

Another big adjustment was moving from the indexing conveyor line that paused at work stations in the old building to a continuously moving line.

'Joining large 3,500–4,000 pound pieces of iron while moving is challenging,' Martin adds, as workers had to learn to assemble while their work rolled along.

Once assembly on this line is complete, the chassis are lifted off their carriers with a new power-and-free conveyor and taken through a wash, paint and curing process.

The cab assembly line features several materials handling highlights too. The conveyor system uses non-powered rollers that accommodate the racks holding the cabs. The rollers, each about a foot wide, are set in two rows spaced about three feet apart, similar to railroad tracks. Workers simply push the carts on the rollers as work progresses. Sections of this conveyor line are designed to raise, lower and tilt to present the work to operators at a more ergonomic position.

The sophisticated cab delivery system was also new to the Racine facility. A monorail retrieves the cab from its cart and carries it overhead to a buffer area where about half a dozen cabs are held until ready to meet the chassis in the main assembly line. Buffering overhead frees up floor space. The two lines are then synchronized together so that the cab can be dropped in perfect position down onto the chassis.

'The systems have done what we wanted,' says Martin. 'Within just a couple days of start-up we had the first product roll off the line on schedule. Overall, the facility has been a great success and is helping us to strengthen our leadership position in agricultural tractors.'

Click on the icon to read how John Deere builds tractors at its award-winning facility in Augusta, GA.