Comau Sells Smart Assembly
One highly flexible machine can replace entire transfer line dedicated to powertrain assembly.
By Tom Murphy Ward's AutoWorld, Feb 1, 2010 12:00 PM

With assembly plants closing and auto makers looking to redeploy machines and assets, executives at Comau Inc. say there's never been a better time to overhaul the manufacturing paradigm.

Wholly owned by Fiat Group, Comau is a leader in industrial automation. Its latest development is the “SmartCell,” which enables for assembly operations the same type of sea change that accompanied computer-numeric-controlled machines for metal cutting some two decades ago.

Today, assembling a cylinder head requires a transfer line, a series of machines each dedicated to a particular task. Up to a dozen machines are necessary to assemble the pieces of the valvetrain, says Ted Brown, Comau's vice president and general manager-powertrain.

The installation of 72 parts in one valvetrain case study is slow and laborious. The cylinder head moves from machine to machine via pallet and conveyor and is rotated as seals, springs, valves, retainers and other hardware are installed.

Cycle time for each machine in the transfer line is between 25 and 30 seconds, which translates into several minutes and significant capital investment to produce one valvetrain.

Comau's SmartCell allows one sophisticated machine to replace the entire line, while completing the assembly with four operations in only 54 seconds.

Operations are combined in the single station with manual or automated kitting operations feeding the assembly cell until the process is complete. The part can be transferred in and out of the SmartCell by gantry, robotically or manually.

“From a lean-manufacturing standpoint, it's all about work-in-process,” Brown says. “Imagine those nine machines — all are going to need parts in-process as well as on-deck. That's a minimum of 18 parts in-process that are not value-added. You have pallets and conveyors, all non-value-added.”

However, the SmartCell has just one part in-process, perhaps one on-deck. “From a lean-manufacturing standpoint, it's not even a comparison,” he says.

The impact on floor space is tremendous. Traditional assembly of 325,000 cylinder heads annually requires about 8,100 sq.-ft. (753 sq.-m). Comau says the SmartCell can do the same job with a mere 2,400 sq.-ft. (223 sq.-m) of space.

Comau says the Smart Cell is ideal for automated assembly of other components requiring tight tolerances, such as turbochargers and transmissions.

Perhaps the most important benefit to the Smart Cell is added flexibility that allows the machine to be reconfigured quickly to produce something else.

Some auto makers are considering retooling assembly lines to build more 4-cyl. and fewer V-8 engines.

“Presently with the serial process, it would take roughly six months of preparation time and three months to tear that system down and reconfigure it for a transfer line with pallets,” Brown says.

Comau says the SmartCell will allow customers to switch out old tools for new ones and change the programming at a moment's notice. “Now this machine can assemble a completely different part over a weekend,” Brown says.

Comau's first customer for the SmartCell is Perkins Engine, which is using the system for cylinder-head output in the U.K. Perkins is purchasing two cells — one to produce valvetrains for 6-cyl. diesels, the other to make valvetrains for 4-cyl. diesels.