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Punch/Plasma Machine Enhances Quality at Bombardier by Jerry Cook, Editor, Metalworking Production & Purchasing | |
"We purchased the machine right after we got a contract from New York City for 680 subway cars," says Bruno Légaré, CAM analyst-technical services, Mass Transit-North America, with Bombardier. Continues Légaré, "To be able to produce all of these cars in the (required) period of time, we knew that we would need additional equipment." The machine is manufactured by W.A. Whitney Co., Rockford, IL. Bombardier's facility in La Pocatière produces subway and rail cars primarily for the North American transportation market. The facility, which is 503,000 sq. ft., has approximately 700 employees. Initially, Bombardier conducted a study that looked at a variety of different machines. "The study looked at price as well as the different characteristics offered by the machines. "We already had one ATC machine that had been installed in 1990. The new machine is smaller than the first machine but it involves the same concept," he says. "We already had a good idea what the Whitney machines can do because the first Whitney machine has been working fine since the day we installed it. "When we finished the study, we were convinced that Whitney offered superior equipment and we are still convinced of that," he adds. Légaré cited several reasons for Bombardier's decision to install another machine from Whitney. For one thing, the 3700 ATC is very versatile. "We came back to Whitney because of the versatility of their equipment.We often work in higher thicknesses of material, where we go up to 3/4 in. in both stainless and mild steel. We found that the Whitney machine was much more versatile and tougher for the kind of job that we are doing," he notes While the machine is capable of punching steel up to 5/8 in. thick, Bombardier is typically punching material up to 1/2 in. thick. In addition to mild and stainless steel, the company also cuts copper and aluminum on the machine. "Using the Whitney machine we can punch and do some very good holes and achieve very good quality with the punching. "We also have the capacity to cut those parts with the plasma which is also a very good process for cutting the kinds of parts that we are doing here," says Légaré. In particular, Légaré was impressed with the quality of the plasma cut delivered by the machine's Hypertherm torch. "The first machine didn't have a Hypertherm torch on it when it was installed but we have since switched it to a Hypertherm torch," he says. The 3700 ATC machine features a positioning area of 60 in. x 120 in.; a maximum plate size of 60 in. x 120 in.; a weight capacity of 1,000 lbs.; and a punching capacity of 40 tons hydraulic. The machine is capable of a maximum material thickness of 5/8 in. for punching; a maximum material thickness of 3/4 in. for plasma cutting; axis speed of 2,000 inches per minute; and punching speeds of 180 hits per minute on 1 in. centers. Other features include a maximum hole capacity of 5 in. diameter; a tool changer with 42 tool stations; a nine second tool change time; bridge frame design; water quench slag removal; and a maximum work clamp spread of 53.75 in. "The machine is used for cutting our primary parts and we punch various holes into those parts. "As well, sometimes when we are dealing with a high thickness of material, we will use the plasma to do cut-outs inside the part. Instead of using the punch and nibbling with the punch," he explains. The 3700 ATC also features an automatic sheet loading system as well as an unloading and a conveyor system for the finished part. The loading system employs 10 vacuum cups and is integrated to a carrier which moves to the pallet and lifts up a sheet and places it in the clamps on the table ready to be punched and plasma cut. The loading system then moves back to the pallet to pick up another sheet. "There is a trap under the table which allows us to move the part on a conveyor right after the part has been plasma cut. The trap then closes and we can restart the machine to cut the next part." The trap or parts door is approximately 18 in. x 24 in. Larger parts that are plasma cut on the machine have to be manually unloaded. When the skeleton is ready to be unloaded, another carrier with two clamps moves into position and the clamps grab the sheet while the carrier moves back carrying the skeleton which will be placed on another pallet. "From the machine, the part will move on and sometimes has to undergo deburring, but not very often, and then it will be set up on the pallet for the next step in the operation," says Légaré. Approximately 90% of the parts will then move on to either a machining center or a press brake, he adds. "Because we are welding the parts, we have to send the parts to machining centers to machine a chamfer on the parts for better welding," says Légaré. Depending on the type and thickness of material being punched and cut and the number and type of holes required, it can take between 20 to 45 minutes to finish a sheet. "All the parts that we do here are made day-by-day if not minute-by-minute. For example, we might make two parts for Item A and then 100 parts for Item B. It changes every day. As a result, we don't have nesting programs prepared (that far ahead of time)," Légaré explains. Bombardier is using OptiPunch nesting software from Optimation with the 3700 ATC machine. One item that Bombardier asked Whitney to change on the machine was the control package, he points out. "Initially, Whitney had the Fanuc 16P control on the machine, but we wanted a control with an open architecture. As a result, Whitney installed a Fanuc 160i CNC open architecture control on the machine." The open architecture control offers a variety of benefits in areas such as network transferring. "We are programming the part outside of the machine and also nesting with a different software. Because each sheet involves a different nest and the nest is used only once, we are doing a lot of transferring on the network. The open architecture control is very reliable and very fast in transferring the programs. As a result, we don't have any downtime with respect to transferring programs," says Légaré. The 3700 ATC machine is more than meeting the company's expectations for performance. "Whitney worked with us and gave us the service and support we needed." (Used with permission from Metalworking Production & Purchasing, April 2000.) Home | All Applications | Punch/Plasma Machines | 3700 Series Applications |
