Porsche - Made Perfect

Made Perfect

Like every Porsche, the Macan epitomizes the optimal interaction of man and machine. The intelligently controlled production process involves multiple locations and many suppliers, and culminates in state-of-the-art production at the Leipzig plant. The process of perfection: How the compact SUV is made.

The floor group opens the dance. At station 1810 in the new body construction area of Porsche’s Leipzig plant, three yellow robots perform their perfect choreography. They weld the front and rear floors as well as the front wheel wells, including the spring strut mounts and longitudinal members, with flowing, almost human movements. The Macan is built from the bottom up. At station 1810 the Macan is baptized—from here on out it’s a vehicle—and receives its birth certificate in the form of a transponder that bears its vehicle-specific identification code.

Shortly before the dance, it was just a collection of individual aluminum and sheet steel parts transported to the body construction supply center by suppliers. From there they are delivered by tugger train to the lines in the plant at the exact right time. Those lines were set up in record time. In less than 26 months, Porsche not only built the body construction area and paint shop, but also restructured the assembly line—without halting ongoing operations. The production floor grew from 79,900 square meters to 245,900 today. That’s equal to about 34.5 soccer fields. It is an achievement that has the full respect of Executive Board Member for Production and Logistics Dr. Oliver Blume: “I’m thrilled with how the team managed this huge job.”

Meanwhile, the first of the three robots has put down its welding gun and taken up the handling grippers with which it lifts the Macan underbody and places it on a transport slide, on which it then proceeds through body construction. This step is followed by assembly of the side sections and roof as well as add-on part assembly, where the doors, tailgate, front wings, and clamshell hood, previously assembled in parallel steps, are integrated in the body. The hood is both a visual and a manufacturing highlight in one operation. “Its shape and size presented massive challenges at every stage of the production process,” says Thomas Riediger, the man in charge of planning the new lines.

The process begins in the Volkswagen plant in Bratislava, Slovakia. There, on the biggest press in the Volkswagen group, the Macan hood is formed. The press works with a force of 91,000 kilonewtons—roughly equivalent to the weight of 4,500 Macans—creating an especially large draw depth (the term when a cup or boxlike structure is formed) of 380 millimeters. The de-stacking, or transferring of the pressed parts, is done fully automatically by robots. This technique, which to date is done only in Bratislava, ensures that the aluminum hood is not damaged.

Back in Leipzig, we are at the last station in body construction, the finish. Two body construction technicians check the surfaces and add-on parts. “The vehicle geometry has to be right for everything to fit perfectly in assembly,” explains Riediger. From here, the bodies are sent to the paint shop.

The Leipzig plant combines state-of-the-art mass production with the exclusivity of a small workshop, where customization is possible. “We can, for example, paint any exterior color that the customer wants,” says Roland Töpfer, head of the paint shop, adding, “That’s what we have ‘Sofa’ for”—the special color system known by its German acronym. The system makes it possible to provide paint volumes for a single car, and even to change the color for each coat of paint.

But first, a quick bath is on the agenda. In preparation for the cathodic electrodeposition (CED) bath, the body is cleaned and de-greased. To reach all hollow spaces, the Macan rotates 360 degrees in the bath. The tailgate, doors—and the clamshell hood—are specially fixed. In the subsequent electrochemical CED process, 380 volts are applied between the bath and the body. This ensures an even coating. The Macan is dipped a total of nine times. Then it goes to dry.

Once the welding seams and flanges—the connection points—are sealed and the underbody protection applied, things get colorful. Primer, base coat, clear lacquer: the order in which the Macan receives its custom exterior. While the body heads into the clear lacquer booth, the painting robots, clad in a white protective film, move into position. Their graceful motions in doing so recall the image of a waiter preparing to carry a tray with his open hand.

With a fine spray, the painting process begins, inside and out. Additional gripper robots chivalrously open doors and open the hood. The robots work elegantly and efficiently, so that 85 percent of the paint actually reaches the body surface, reducing overspray to an absolute minimum. Using a dry paint droplet removal system, the excess paint particles in the air are bonded to a limestone ­powder and disposed of. There is no waste. The pulverized limestone is completely recycled. “It goes to a cement-maker. Cement is fired to 2,000 degrees Celsius, so nothing is left of the paint,” says Töpfer.

The Porsche plant is an environmentally friendly plant. The photovoltaic facility on the roof of the body construction area, for example, generates up to 800,000 kilowatt-hours of solar energy annually—roughly the annual energy consumption of over 150 average four-person households. The paint shop operates at up to 80 percent CO2-neutral. The required heat is supplied by a biomass power plant located right next to the plant. Sustainability as an expression of social responsibility, as board member Blume puts it.

The Ergo-Lux tunnel, a light tube outfitted with economical LED modules, is an equally good fit with the concept. The highly uniform reflected light is optimal for checking the paint job: two employees carefully inspect a hood and run their hands—without gloves—across its surface. This is the only way to detect the uneven spots that they then polish out. Now the Macan is ready for assembly.

It’s the playful ease that first catches the observer’s eye. Bodies float by on overhead conveyor units or travel from one production area to another on lift tables in perfectly timed sequence. Electric tugger trains run back and forth supplying the assembly lines with material. It is a precisely coordinated harmony that seems to follow a higher order. Behind it all is the pearl necklace principle: a logistics process that functions without warehousing parts and in which the parts arrive at the assembly line “just in time, just in sequence”—that is, at just the right time and in the right order.

But it’s not just the system—the employees exude this attitude as well. Some 1,500 employees were hired in the course of the plant expansion. All were individually qualified and integrated in the team. “Working for Porsche means approaching things with perfection and passion. Every single employee bears responsibility, but we achieve success only together,” says Oliver Blume. The board member is a team player. To understand all of the new work steps, during the transition period he joined the lines himself and worked on the production sequences.

In assembly, a whopping 225 stations await the Macan. It starts together with the Panamera on the door line. Here the doors are first finished before disappearing once again on the interior line. This simplifies the subsequent assembly steps, in which the doors would be in the way. The completely assembled cockpit, for example, is integrated with a special lifting device.

Before the underbody line, the body moves from the lift table to the overhead conveyor unit “to make work on the underbody more ergonomic,” as head of assembly Martin Kahmeyer explains. One principle of the Porsche production system: the process in which a part is installed only works as perfectly, simply, and quickly as possible if the employees have an easy job of it from an ergonomic standpoint.

Indispensable for the entire value chain is the quality assurance measures, as reflected in the zero-defect principle, among others: “Don’t accept defects, don’t make mistakes, don’t pass errors forward,” is the motto. One quality assurance measure introduced by Porsche is a special master jig, called a Meisterbock, for body and assembly parts. The precise fit of assembly add-on parts, for example, is tested by the inner Meisterbock. “With the joint wheel and these joint pins we check the measurements of the gaps,” explains production director Dirk Kolar as he places one of the pins in the joint between the rear light and rear valance. Perfect. “At regular intervals we invite the suppliers and show them where they have to be more precise.”

The Macan has left the underbody line with important parts such as the brake lines and the tank on-board. On the exterior line it not only gets its doors back but also receives its rear window and windshield—and the Porsche crest now decorates the hood. Now it heads to the mix line. It’s called the mix line because this is where the Cayenne comes in, bringing together the factory’s three models on a single line—a specialty of the Leipzig plant. By the way, the six-cylinder gas engines come from Stuttgart-Zuffenhausen. They’re delivered to the assembly supply center in Leipzig in trucks, and from there to the drivetrain enhancement line, which operates parallel to the body assembly.

While the body swings in on the overhead conveyor unit, the chassis and drivetrain approach their union on a driverless transport system. The special moment of joining happens fully automatically. The witnesses are the employees one station later, who screw the spring struts into the mounts. This step is followed by the filling with fuel, brake fluid, coolant, and motor oil. At the end of the mix line, the Macan is standing on its own four wheels. All that’s left now is the test facility, or finish.

Porsche added an extra line for the new SUV. This is where the software is uploaded, brakes tested, headlights set up, driver assistance systems calibrated, and—for the first time—the engine is started. Before it undertakes its journey to the customer, Porsche asks the Macan for one last dance. But this time, it is not for a round with the robots, but a whirl around the warm-up track. The Macan is ready for the world.

Dr. Oliver Blume knows all the components in the Macan production process from firsthand experience: “Even as a board member I’m a part of the team, and that’s why it’s crucial for me to know the technology in-depth.” And what better way to transmit the Porsche spirit and passion for details than for a board member to get his hands dirty on the production line?

By Thorsten Schönfeld
Photos by Stefan Warter

Macan – What happens where?

For the Macan, Porsche expanded the Leipzig location into a complete plant. An overview of the processes in body construction, the paint shop, and assembly.

1 Unloading train station
2 Supply center
3 Decoupling module
4 Assembly line
5 Final assembly
6 Pilot and analysis system
7 Cafeteria
8 Integration center
9 Customer center

10 Body construction
11 Paint shop
12 Supply center expansion
13 New engine pre-mounting
14 New finish line
15 Integration center West
16 Pedestrian bridge
17 Body bridge

Body construction

1 Manufacturing the hood
The Macan’s aluminum hood is a manufacturing masterpiece. The individual parts are welded and riveted. And between the outer and inner parts, a special high-tech adhesive is used.

2 Floor group
The birthplace of the Macan, this is where the floor group emerges. The Porsche also receives its “blueprint”—a transponder system with all vehicle-specific information.

3 Building the car
First the underbody is built, followed by the platform. At this stage, the side sections and the roof are added to the underbody.

Paint shop

1 Primer
The first coat of paint is a primer or prime coat. This comes in three color tones (white, anthracite, and light blue). It is coordinated with the top coat to follow.

2 Top coat and clear lacquer
The primer is followed by the top coat and thus one of eleven colors offered for the Macan. It is also possible to choose any custom color. Finally, a clear lacquer seal is applied.

3 Ergo-Lux tunnel
To check the paint job, all Macans pass through the new light tunnel. This economical device is outfitted with LED modules whose light is projected onto the body by means of mirrors. This generates a horizontal light that illuminates even the smallest impurity.

Assembly line

1 Installing the cockpit
One of the largest complete modules is integrated into the vehicle at this station: the cockpit. The assembly workers perform this precision job with a handling device that enables them to maneuver the cockpit into the vehicle.

2 Hanging unit
At the end of the interior line, the vehicles are moved from the lift table to the hanging unit in order to make the work on the underbody and difficult-to-reach areas more ergonomic for the workers.

3 Union
Here the complete chassis, the drivetrain with engine and transmission, and the complete body are fastened together.