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St. Thomas, the Home of Ford's CVPI
The St. Thomas Assembly Plant, near London, Ontario, Canada, is the home of the Panther platform cars: the Ford Crown Victoria, Crown Victoria Police Interceptor (CVPI) and Crown Sport, and the Mercury Grand Marquis and Marauder. The Ford CVPI solidly maintains about 80% of the total North American police vehicle market.
A two-hour drive east of Detroit along Highway 401, the plant sits on a 635-acre rural site just north of the small town of St. Thomas. The assembly plant has everything from basic sheet-metal fabrication to high-tech, computer-controlled manufacturing.
The plant traces its roots back to May 1966 when Ford began construction of the St. Thomas Assembly Plant (STAP) in the farming country of southwestern Ontario, about halfway between Windsor and Toronto, a scant 8 miles north of Lake Erie.
The plant covers 2.4 million square feet and features a 12-mile-long assembly line. About 2,700 employees work on a two-shift schedule that operates from Monday through Friday.
In keeping with modern automotive manufacturing standards, the plant meets both the ISO 14001 standard for environmental efficiency and the ISO 9001 standard for quality. Over its 34-year history the plant has won numerous environmental and quality awards.
Vehicle production started in 1967 with the Ford Falcon, followed by the Ford Maverick in 1969. The Ford Pinto and Mercury Bobcat were also assembled there from 1970 through 1980. The Ford Fairmont and Mercury Zephyr were next up, built from 1977 through 1980. The sporty Ford Escort EXP and Mercury Lynx LN7 began production here in 1981. They were joined by the regular Escort/Lynx twins in 1981.
In October 1983, the St. Thomas Assembly Plant began production of the Ford LTD and Mercury Marquis in their original square body style. This was the beginning of the plant’s now 21-year history of building cars for law enforcement. Around 174,000 of these Panther platform cars are produced annually. This is the only assembly facility for the Crown Victoria and Mercury Marquis.
The vehicle assembly process begins in the body area where sheet metal stampings arrive on an almost daily basis from a Ford stamping plant near Buffalo, NY. This part of the plant is relatively dark, quite noisy, and staffed largely by robotic assembly machines and welders.
Each vehicle body is assembled on a skid that holds the body in a secure and precise manner on its journey through the plant. The skids are moved throughout the plant on a system of floor-mounted chains that resemble giant bicycle chains.
To clearly identify each vehicle on its path through the assembly process, a radio-frequency identification (RFID) tag, which is about the size of a typical battery-powered smoke detector, is attached to each skid.
The tag then wirelessly communicates with each assembly process along the way so that each vehicle is assembled according to the customer’s order. It defines the wheel-base length, primary body color, custom paint colors (for police and taxi fleets), various police accessories such as “A” pillar mounted spot-lights, various engine options, interior colors and trim, and every other major and minor detail about its assembly.
The floor pan section of the vehicle is the first body assembly to be completed. Long wheelbase models are pulled from the line shortly after this point where they are cut completely in half just behind the “B” pillar. An extension module is then welded into place to extend the rear passenger section of the vehicle by 6 inches to create the longer wheelbase model. Longer side panels and roofs are added to these stretched floor pans before the bodies rejoin the regular line.
To improve body strength and provide better resistance to side impacts, a substantial side-impact bar is bolted to the body pan behind the rocker-panel area in the early stages of the assembly process.
Regular wheelbase vehicles have their roofs attached and welded into place in a two-stage process that was quite fascinating to watch. A robot arm picks up a roof panel from its supply pile, flips the panel over by 180 degrees so that the inside is facing up. The panel is then maneuvered under a sealant-dispensing machine.
While the machine dispenses sealant, the robot very deftly moves and rotates the roof panel under the dispensing nozzle so that sealant is precisely placed on all the required areas. The robot then quite rapidly flips the roof panel over again and quickly lowers it to within about 1 inch of the body shell.
After a few careful adjustments, it places it precisely onto the correct place on the body. The body then moves just a few yards down to the welding booth where in a matter of about 30 seconds, the roof is welded to the body by several groups of welding robots.
One set of robots welds the roof into place along the front and back, while another set of robots does the same along both the left and right sides of the body. Once the roof is in place, the bodies really start to resemble the final product.
The next stage in the assembly process is the door installation station. Here, pairs of robots work quickly in a cleverly choreographed set of moves to precisely install all the doors. While one robot picks up the completed doors and maneuvers them into place, the second robot reaches through the window openings and quickly bolts the door into place. Because the accurate installation of the doors is so critical to the snug fit and the overall quality of the vehicle, this process is best done by these robotic assembly machines.
Vehicles destined for taxi and law enforcement use are again separated from the main line just beyond the door installation station, where they will have a hole drilled into one or both of the “A” pillars for spot-lamps and a hole drilled into the roof for roof-lights or a taxi sign. Robotic drills quickly and precisely drill the necessary holes before the bodies are again returned to the main assembly line.
After the body shell is completed, it enters the paint shop section of the plant. Here, the atmosphere improves greatly with the plant becoming much quieter, cleaner, and brighter.
Before being painted, the completed body shells are cleaned and dipped in a special rustproofing solution that is applied through an electrostatic process. The bodies are then painted in a special self-contained paint booth line by a series of robotic painting machines. Only the primary body color is applied here. In addition to Ford’s current stock-colors, large fleet buyers can have their custom colors painted here too.
Ford also offers three standard two-tone color options for law enforcement, such as the famous police black-and-white combination, and custom two-tone paint jobs for larger state police agencies.
Vehicles destined for the stock two-tone and custom paint schemes are separated from the main line and sent to the custom paint shop. The custom paint shop team then carefully tapes and masks the generally white body shells in all the appropriate areas before the vehicle is sent to the custom paint booths to have the unmasked areas painted the appropriate colors. Once the two-tone and custom painting is done, these vehicles rejoin the main line on the home stretch and the final assembly area.
The final assembly area is where most of the employees work and where most of the fine manual labor gets done. Since the Crown Victoria and Grand Marquis use a body-on-frame design, a large amount of the final assembly work is done on the frame section before it gets paired to the now complete body shell.
A number of engine and transmission combinations are installed here after arriving from a separate plant. Standard civilian engines, law enforcement engines, and those destined for Middle Eastern customers are clearly discernable as they arrive at the installation area from a supply line that descends from the ceiling in classic assembly-line fashion.
In addition to all the standard internal equipment installed in every vehicle, this is also the place where all the law enforcement specific packages are also installed. The Base and Complete Police Prep packages (65A and 68P respectively) and the Visibility Package (65W) options are added here.
The base prep package consists mostly of a number of specialty wiring harnesses and extra power distribution points needed for law enforcement vehicle lighting and equipment demands.
The complete prep package adds to the base package by including such useful options as the excellent console mounting platform, and an extra wiring conduit to connect custom equipment between the front of the passenger compartment and the trunk. It also includes dual trunk storage boxes, a rear communications service tray, and a variety of other little bonus pieces. The visibility package adds an extra switch box that controls a pair of flashing rear deck LED lights, a strobe power supply, and a light relay center.
In response to concerns about fuel tank damage from high-speed rear impacts, Ford has also made available, as a factory-installed option, the new TrunkPack. It is manufactured from high-density polyethylene and reinforced with a DuPont Kevlar® lining along the forward side of the box. It is designed to help reduce damage to the vehicle’s fuel tank by preventing items stored in the trunk from being forced forward through the front trunk-wall during a high-speed rear-end impact.
Another safety improvement is the new rear-suspension component axle-guard that is installed in all law enforcement vehicles. It encases portions of the rear suspension system to prevent the suspension components from damaging the ends of the fuel tank during a high-speed rear-end impact.
The amount of precision required to produce a tightly built and durable vehicle that is used primarily for the demanding environs of law enforcement and taxi use demands a great deal of attention to quality design and assembly.
To maintain this precision, numerous tests and examinations are conducted throughout the assembly process. Three vehicle bodies are pulled at random from the assembly line in the body area every day and subjected to rigorous inspections of up to 300 reference points on the body shell.
A coordinate measurement machine is used to precisely measure these reference points to within one-thousandth of a millimeter. If any of the 300 points are outside of the specified tolerances, the technicians can determine where in the assembly process the problem originated. The line is then paused while maintenance people attend at that point in the line and adjust the appropriate piece(s) of equipment.
Various other dimensional checks are also done at random in the assembly process to ensure that the bodies are assembled correctly and within their very tight tolerances. Again the value of the skid that each body is transported through the facility upon also helps to ensure that the vehicle is assembled accurately.
While the efforts of the plant’s employees are put toward building top quality vehicles, there are actually a few employees that spend their days and evenings tearing them apart.
In the weld destruction booth, several employees randomly separate various subassemblies and carefully pull apart every weld to determine its size, shape, and placement. Faults in the welds, such as incorrect size or inaccurate placement, point toward problems with the welding robots and to potential problems with the vehicle in the future. Once a week, an entire unpainted vehicle body is removed from the line, and every weld is examined and pried apart during a thorough inspection.
While most of the employees are directly involved in the assembly of the vehicles, there are also numerous teams of specialists that keep all the machinery and robots functioning up to their specifications. The maintenance crews also work hard keeping various systems stocked with sealants, paints, lubricants, and other peripheral equipment.
A great deal of engineering and attention to detail goes into the modern automotive manufacturing process. It was a fascinating experience to witness the entire assembly process in the matter of about two hours, and watching the raw sheet-metal stampings slowing coming together into the shape of a vehicle, and eventually rolling off the assembly line as a fully functioning police vehicle.
Tom Rataj is a detective-constable with the Toronto Police Service in Toronto, Ontario, Canada. He is currently in his 26th year of active service. He may be reached at firstname.lastname@example.org.
Published in Police Fleet Manager, May/Jun 2006
Rating : Not Yet Rated
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