Auto Makers Undergo Paint Shop Makeovers
Major automakers are making big changes to their paint and coating lines, especially in the area of improved efficiencies, lower utility costs and faster processes.
Ford Motor Co. says it has grown its industry-leading 3-wet paint capacity by 50 percent in 2014 by adding the environmentally friendly process to four additional plants on three continents. The actions will reduce carbon dioxide emissions by roughly 15-25 percent at those facilities.
Ford has also announced a new “3D Dirt Detection Technology” that uses hi-resolution cameras to eliminate dirt particles smaller than a grain of salt on vehicle paint surfaces. Six plants have the technology now, with two more getting the equipment in by the end of 2014.
At General Motors, the company is in the midst of a $2.8 billion overhaul of its manufacturing operations, including a focus of making its paint shops more energy efficient and reducing coating times.
The paint shop changes alone often result in a 50 percent reduction in energy costs per vehicle, a huge saving metric for an industry trying to rebuild itself and compete on the global level.
“As the world faces sustainability challenges, we strive to be part of the solution—from designing more efficient vehicles to transforming how they’re built to reduce environmental impact,” says Mike Robinson, vice president of GM Sustainability and Global Regulatory Affairs. “There is a strong business case to be made for integrating energy-efficient practices at all of our global facilities.”
Case in point for GM is its Orion, Michigan, assembly plant, which manufacturers the Chevrolet Sonic and the Buick Verano.
GM demolished the old paint shop and hired the Gallagher-Kaiser design firm to build a new one in 2011 that was 10 percent smaller than the original, which saved on utility costs and also freed up much-needed floor space.
The new paint shop uses 50 percent less energy per vehicle, mostly from using natural and landfill gas instead of the coal-fired burners it previously used.
Eric Stevens, GM vice president of Global Manufacturing Engineering, says using nearby landfill gas to generate steam for heating and compressed air saves about $1.1 million a year in energy costs, but it also reduces the amount of greenhouse gases, sulfur dioxide and nitrogen oxides released in the air.
Removing 14,000 Cars
The numbers are staggering: About 80,000 metric tons of greenhouse gas emissions are reduced each year at the Orion plant alone—equivalent to the annual emissions of 14,000 vehicles.
The improved painting process also eliminates about 108,000 pounds of solvent emissions. Those savings equal out to about $40 less on the sticker price per vehicle.
“Orion is a great example of the latest technologies employed by GM manufacturing around the globe,” Stevens says. “As we converted the facility to support the small car program, we took every opportunity to engineer in flexibility and lean manufacturing concepts.”
Much of the cost savings is attributed to the water-based 3-wet painting system, which GM says it was the first automaker in the U.S. to fully utilize.
The painting process removes the need for a primer bake oven, usually placed between the primer application and the color coats. With the 3-wet system, the three layers of paint are continuously applied one after another while still wet, before making a single pass through the bake oven.
The process actually improves the car’s glossy sheen, reflectiveness and durability, says Mauricio Pincheira, paint manager at GM’s Orion plant.
“Cutting our greenhouse gas emissions and reducing energy consumption were key to implementing our water-based 3-wet paint process,” says Pincheira. “We want to provide a durable paint that impresses our first-time Sonic customers and maintain the tough environmental standards we have across the company.”
Those are the same reasons Ford is ratcheting up its paint shops into the 3-wet process. The automaker, which says it was the first to implement the high-solids solvent-borne 3-wet technology on a global level in 2007, had eight plants in North America, Asia Pacific and Europe that use the process, and last year added four more paint shops to its network of manufacturing operations: Flat Rock Assembly Plant, Flat Rock, Michigan; Kansas City Assembly Plant, Claycomo, Missouri.; Jiangling Motors Co. Ltd., Jiangxi/Nanchang, China; and Valencia Assembly Plant, Valencia, Spain.
Bruce Hettle, Ford’s director of manufacturing engineering, says the 3-wet process has helped the company reduce carbon dioxide emissions by 15-25 percent and VOC emissions by 10 percent at facilities where the process is used.
“The 3-wet paint process is significantly more advanced than conventional technologies in applying durable paints in a high-quality, environmentally sound and cost-efficient manner,” says Hettle, who estimates that the faster painting system cuts 20 to 25 percent of process time in the paint shop.
And thanks to eliminating the stand-alone primer application and dedicated oven, which Hettle says reduced the overall paint booth size, Ford saves electricity from blowers that usually circulate massive volumes of air through paint booths, and cuts down on its use of natural gas needed to heat the air and ovens.
“This results in significant reductions of CO2 emissions, as well as reductions in VOC compared with current medium-solids and solvent-borne paints,” he says.
$500 Million Upgrade
After testing the paint process at its Avon Lake, Ohio, assembly plant, Ford first used the 3-wet system at its Chennai, India, plant in 2009, part of a $500 million upgrade to the manufacturing plant, but with an eye toward finding a better way to paint cars that reduced time and costs.
Ford partnered with BASF and PPG and facility supplier Dürr for the Chennai project, and what they found was that the new 3-wet formulation contains more paint solids, which meant less paint was needed to cover a vehicle than the medium solids technology. Their laboratory tests also showed that the high-solids, solvent-borne paint provided better long-term resistance to scratches than water-borne paint and medium-solids solvent-borne paint.
The Chennai paint line also doubled the plant’s hourly vehicle capacity, going from 15 vehicles per hour to 34 vehicles per hour.
“It’s not very often that we can deliver quality, cost and environmental objectives with a single paint technology,” says Kalyan Murugan, project manager for Ford India’s paint shop.
The success with the 3-wet painting system led Ford’s engineers to look for even more ways to improve the finished paint coat on its vehicles, which led to the car company announcing recently that it was installing high-resolution cameras to generate a 3D model so its paint shop staff can identify and eliminate dirt particles on cars, often smaller than a grain of salt.
The system cues operators on where to polish and buff out imperfections so the vehicle can then start the 3-wet paint process.
In testing at Ford’s Dearborn truck plant in Dearborn, Michigan, last year, the dirt detection technology improved paint quality and reduced customer complaints of vehicle surface finish by 82 percent, as measured by customer warranty data for F-Series models produced at the company.
“This system ensures better paint jobs and surface finishes for Ford customers around the world,” says Tom Dougan, Ford’s project manager, Global Paint Applications.
Here’s how it works:
Ford’s dirt detection technology takes microscopic scans of each painted vehicle surface, and then cues final assembly operators to address repairs where necessary. In the past, paint and surface inspections were based on human-eye examination.
The 3D imaging system applies varying degrees and angles of light while scoping the paint surface of vehicle bodies to identify dirt in paint and other irregular paint conditions.
High-resolution images (3,150 images are captured in 15 seconds for every vehicle made) are stitched together for a full 3D image that is digitally compared with a perfect computer model.
Along with the Dearborn truck plant, the automated inspection system is now being used in the U.S. at Ford’s Kentucky truck plant as well.
“This is one of the most exciting integrations of optical science and digital technology in the automotive industry,” Dougan says. “By combining innovations in vision technology, processing speed and software, Ford continues to invent new technologies that give our customers better paint quality and surpass competitor offerings.”
Information for this story supplied by Ford and General Motors.
An overview of spraying, dipping, flow coating, and everything in between.
Specific questions about zinc phosphate and pretreatment are answered in one article...
Choosing the right conveyor system, coating technology, and ancillary equipment.