Americans spend an average of eighteen hours per week in a car. Yet most drivers don’t think about the origins of the vehicle that gets them from Point A to Point B. Beyond vague images of heavy machinery and workers in hard hats, the actual process of building a car is a mystery to most people. Let’s take a look at the system that plays such an important, behind-the-scenes role in American life.
A little background: Henry Ford is known as the father of the American automobile not only because he made cars affordable to the general public, but also for his innovation in developing the assembly line for mass production. Under the assembly line system, workers complete specific tasks as the car moves through production. This system allows for workers to achieve a level of expertise that increases efficiency and expedites the manufacturing process.
Rather than constructing cars entirely from scratch, most modern auto manufacturers acquire their parts from suppliers around the world. These parts are then used to assemble cars in the manufacturer’s plants. Unlike Henry Ford’s assembly lines of the past, modern lines rely heavily on robots to install and assemble parts under human supervision.
- Welding is a prominent part of the auto manufacturing process, especially in the initial stages. The car’s floor, roof, and side body panels are tack welded within the fixture of the body frame. Thousands of reinforcement brackets are then welded throughout the frame to provide strength and support.
- Moving components such as the car doors, trunk, and hood are affixed to complete the car’s body.
- Phosphate coating is then applied to clean the metal body and provide a foundation for painting.
- The next stage is painting, which requires a few coats. A prime coat is applied first by dipping the car in a large tub unit that sends an electric current to anodize the primer onto the metal. The car is then “baked” at about 200 degrees to finish the priming process.
- A few layers of topcoat paint are then sprayed on robotically and baked again to finish drying. Finally, a protective clear coating is applied and baked a final time.
- The next stage is where the car’s body shell is filled out with all the interior parts that make the car function. This installation includes everything from windows, air conditioning, and car seats to the vehicle’s engine, power train, and transmission. Ultrasonic welders play a huge part in this stage as well, helping to construct the car’s instrument panels and electrical components. Ultrasonic welding can do the same job that glue does in a fraction of the time, while also creating a stronger bond. Because of its shallow weld depth, it is the most effective welding method for thin materials like plastic and aluminum. As manufacturers seek to make cars even more lightweight and efficient, plastic welding will only continue to grow.
- The wiring is completed in the last stage, as well as the installation of the wheels and fuel tank. The vehicle then undergoes a number of quality-control tests to ensure proper function. Then, it’s off to a dealership and into your driveway!
Auto manufacturers will continue to look for technology and methods that will make work environments safer and more efficient. Because it does not require open flames or produce electrical arcs like traditional welding methods, ultrasonic welding is a good bet to become even more prevalent in the manufacturing process.