General Motors Corp. is creating global standards for its thermoplastic bumper fascia that will streamline engineering and production throughout its supply base.
The two sets of standards - one for painted thermoplastic polyolefin fascia and one for molded-in-color fascia - replace requirements that varied among six different engineering regions.
``We want to eliminate waste,'' said Charles Buehler, GM technical integration engineer for materials engineering, during the Society of Plastics Engineers' TPO Global Conference, held Oct. 9-11 in Sterling Heights.
The Detroit-based carmaker already knows the switch will work. Two years ago it rolled out unified standards for TPO fascia in North America, replacing more than a dozen specifications with two: one for painted TPO, the other for unpainted.
While the move eased complications related to engineering and resin supply, it also eased production throughout the supply chain, Buehler said.
Since there was one set of standards for what the company would allow in shrinkage, toolmakers knew how much to allow for on every injection mold tool they built. Molders knew exactly how the resins would react in the press, so they could speed mold cycles and production. Suppliers and GM knew how the fascias would handle paint and could stop worrying about continually recertifying resins and instead focus on performance, Buehler said.
``You spend your time and money more wisely in the value chain, rather than doing all of this busy work,'' said Steve Dwyer, senior vice president for advanced polyolefins with TPO supplier Basell USA Inc. in Lansing, Mich.
The global standards will be phased in by 2010, with some platforms potentially using them as early as 2008. GM will continue using resin from a cross section of global and regional suppliers.
While the current effort only looks at standards for bumper fascia, Buehler said he expects the program could extend to other materials and other parts. Even on fascia alone, the specifications cover a huge amount of material - about 300 million pounds annually, since GM makes about 15 million vehicles globally each year, and each vehicle has about 20 pounds of fascia TPO, he said.
There are about 4,000 parts on each car GM makes, he said, and 4,000 different sets of standards globally. That adds up to as many as 16,000 different sets of specifications the carmaker and its suppliers must tackle.
Those standards set performance attributes in issues such as stiffness, the ability to handle weather extremes, and tolerance to ultraviolet-light rays, shrinkage and expansion in cold and heat.
GM did not merely extend its North American standards globally, Buehler said. Instead it looked at performance requirements from throughout its regions and picked highlights from each area in creating the new specs.
As a result, GM will have a standard that improves on the demand for dimensional stability compared with previous North American specs, he said. Likewise, there will be changes in cold-weather performance for TPO in Australia and South America, which was not as tough as its counterparts in North America or Europe because the regions did not require it.
``We take the best of the best from the world, combine it into one [specification] and offer it up to the world,'' Buehler said. ``This is not just a North American vision; this is a global vision.''
Some of GM's global competitors already have global standards, Dwyer said, but they have not been the rule for North American carmakers up to this point.
But with the change, GM's resin suppliers will know precisely what targets their materials must meet in any part of the world for a GM vehicle, Dwyer noted. That means knowledge gained on a compliant production line in the U.S. can be passed on to lines in China or Germany or Brazil.
``It helps quite a bit because you don't have to develop the product three or four times,'' he said.
And it leads to precisely the kind of streamlined lean manufacturing that companies need to survive, Dwyer said. Suppliers expanding in developing regions to support automakers also know upfront the kinds of infrastructure needed to provide the material, said Doug Mosier, Basell's regional manager of advanced polyolefins.
Suppliers then can turn their attention to improving the performance of those approved materials, rather than tweaking the materials themselves from one country to another, Dwyer said. That could mean better fit and finish of final parts, improved adherence to in-mold films, faster cycle times or less scrap.
Each improvement somewhere in the supply chain means an overall improvement for everyone, Buehler said. ``None of us lives in a vacuum,'' he said.