Building An Ambulance
Ambulance manufacturing is as much about design, engineering and technology as it is durability and functionality.
Braun Industries in Van Wert, OH, (www.braunambulances.com) manufactures up to 350 ambulances each year for some of the largest municipal fleets in the country, including Chicago, Boston and Miami-Dade. Since the needs of each fire department and non-municipal customer differ, the company's applications engineering department must pay careful attention identifying the equipment and layout needed to fulfill customer requirements-down to the location of oxygen outlets, auxiliary control panels and cabinetry-a process that requires working with more than 600 medical and safety equipment suppliers. Once the details have been nailed down, the design engineering group uses SolidWorks software to develop 3D CAD files outlining the exact number of pieces needed-anywhere from 300 to more than 900-to build the box that is fitted on the back of the cab. Concurrently, electrical engineers verify the equipment selected by the customer will work within Braun's peer-to-peer multiplex electrical architecture.
Once the design has been approved, the fabrication department converts the SolidWorks files onto SigmaNest (www.sigmanest.com), which automatically optimizes the layout of parts on each of the 8- and 12-ft. sheets of 1/8-in. thick marine-grade aluminum, reducing waste and improving efficiency. The parts are cut with a plasma torch, Trumpf punch or Komo router, then brake formed; it takes an average of 4 hours to cut as many as 80 sheets of parts for each box. The use of SigmaNest also allows Braun to store detailed specifications for each truck in a database for reference in case replacement parts need to be fabricated on short notice. All of the pieces are sent to the welding shop where they are spot welded together by hand, completing the basic box assembly. Then it moves onto paint.
The box moves to final assembly, where lean manufacturing principles are followed. The 110,000 ft2 assembly hall is arranged by "value streams": chassis prep, fabrication and quality. The combined chassis and box-now called an "ambulance"-travel through the assembly process via a "work center" arrangement, defined as specific areas of assembly, such as electrical or upholstery. Parts are kitted by truck number and delivered line-side for each of the work centers; there are up to five work centers per assembly station. Once the kitted parts are placed on the truck, the ambulance is moved to the next station, where another work center is completed. The entire build process, from the first cut of aluminum to the final quality check, takes up to 35 days, with cost ranging from $85,000 to $350,000.
Digital mock-up tools sit nicely between heavy-weight, complex CAD systems and lightweight CAD viewers. Every automotive enter-prise should have one of these tools. And in time, will have one.
General Motors is working with Autodesk on utilizing advanced design software and 3D printing capabilities to develop parts that are not only lighter than those otherwise developed, but which combine what would otherwise be separate parts, thereby reducing manufacturing complexity.
Visualization is an affordable technology for quickly and realistically depicting data visually. Besides being great for marketing, visualization saves prototyping time and expense, and it lets users see physical conditions not obvious in 2D or 2 1/2 D.