Founded in 1978 as a contract snow and ice removal company, Arctic Snow & Ice Control, Inc. has developed a unique, patented sectional snow plow that automatically adjusts when plowing over obstacles up to nine inches high. This feature allows the company's plows to clear snow and ice in one pass, while reducing damage to pavement, obstacles and the snow removal equipment.
Demand for the company's innovative, efficient snow plows, which it sells under the trademarked “Sno-Plows” name, has snowballed in the cold, icy Midwest.
During the snow season — mid-November through mid-April — Arctic Snow & Ice Control employs nearly 500 people. Year-round, the manufacturing side of the business employs 20 full-time workers in its 67,000 sq. ft. plant in Bradley, Ill.
Operating 16 hours a day, six days a week, Arctic Snow & Ice Control could weld enough moldboard — snow blade — sections and frames to produce only five or six finished snow plows a day, or two to three per shift, and wanted to double that capacity while operating one 10-hour shift five days a week.
The company's goal was to produce about 50 to 60 moldboards per day — enough for 10 to 12 snowplows. A variety of snow plow sizes are available with three to eight moldboards sections in each, but the most popular models are comprised of four to six sections.
The company needed a way to increase its productivity in an area of the country where skilled manual welders are scarce and expensive.
“Implementing robots has improved our productivity six to seven times over our previous manual welding process. Our business is growing as a result and we are planning to hire more workers to help keep up with the robotic welding cells,” said Jeff Sexton, director of manufacturing, said. Sexton has been with Arctic Snow & Ice since 2003.
Sexton had been interested in robotics since he was a teenager. He and the company's founder and owner, Randy Strait, realized that robotic automation offered a clear path to reach their goals.
In 2007, they went to the Fabtech/AWS Welding Show in Chicago to see what robotic welding had to offer.
They wanted a one-stop solution from a company that would provide robotic systems integration and a full range of training and support services — not just robots. From the start, they said one robotics company impressed them with its professionalism, technical expertise and range of robotic solutions.
In October 2008, Arctic Snow & Ice installed the first of two Motoman robotic welding solutions — one for welding large or small moldboards and a second to weld snow plow frames.
Moldboard Welding Cell
Made of 0.125 in., A36 mild steel, large moldboards are approximately 32 in. wide × 42 in. high, and weigh 110 lbs. Small moldboards are 30 in. wide × 30 in high, and weigh 80 lbs. Depending on the model, each moldboard requires approximately 65 welds that range from 3 in. to 4 in. in length. Manually welding the large moldboards requires 40 to 45 minutes, while the smaller models require 30 to 35 minutes.
“We knew from experience that welding the rolled steel moldboard parts requires shorter welds performed in a specific sequence to avoid part distortion,” Sexton said.
“Shorter welds are stronger, and won't fracture in the field, despite the cold environment and constant stress the snowplows undergo as they perform snow and ice removal,” he added.
The high-productivity, three robot cell the company implemented to weld moldboards is a standard, pre-engineered Motoman ArcWorld III 6300XHD welding cell that has custom-designed fixtures.
The welding cell consists of three Motoman SSA2000 Super Speed Arc welding robots, the newest and fastest models in Motoman's application-specific Expert Arc series. The robots feature a 3 kg (6.6 lb.) payload, 1,390 mm (54.7 in.) reach, and ±0.08 mm (±0.003 in.) repeatability.
The streamlined design of the SSA2000 robots is designed to improve torch access into tight places, and integrated upper arm cabling is designed to eliminate cable flip and reduce harness wear and maintenance downtime while preventing interference between the robot arms, fixtures, positioner, and other equipment.
All three robots are programmed using a single teach pendant and an NX100 TRC (triple robot) controller. Advanced features in the Motoman NX100 controller are designed to simplify programming of the three robots, and to allow them to work in close proximity without collision.
The robots are equipped with Miller Auto-Axcess 450-amp welding power sources and water-cooled Motoman Tough-Gun torches. The torches use 0.045 in. steel wire that is fed automatically from 1,000-lb spools. Shielding gas is a 75/25 mix of argon/CO2. Three reamer/sprayer nozzle cleaning stations with automatic wire cutters are included in the cell, as is Motoman's high-speed ComArc touch-sensing weld function.
The ArcWorld cell includes an AC servo-driven Motoman MRM2-900M1X dual headstock/tailstock trunnion positioner with a 900 kg (1,984.2-lb) payload capacity per side and 6.5-sec. sweep. The span between the headstocks and tailstocks is 3 m (9.8 ft).
Motoman provided two sets of custom fixture frames — one per side of the positioner — with two fixtures per frame. The system can be run with the same size moldboards in both sets of positioner fixtures or with a pair of small moldboards fixtured on one side and a pair of large moldboards on the other. Minor, manual changeover of fixture details is required to allow each fixture to hold pairs of large or small parts.
The welding cell includes cell guarding that meets the ANSI/RIA 15.06-1999 safety standard, including 8-ft. high safety fencing with arc flash protection curtains, a personnel access gate with positive-break safety switch and dual-channel hardware; light curtains at the positioner load/unload stations, and a three-color status beacon.
“We had the new ArcWorld cell up and running moldboard production within two days of getting it on our floor,” Sexton said.
“Motoman's application technician did the initial programming of both sizes of moldboards for us initially. I've taken training at the Motoman Technical Center and currently do most of any robot programming and maintenance. Motoman's training is good and we plan to send another one of our guys soon,” Sexton said.
The second cell is a modified Motoman FabWorld welding cell that Arctic Snow & Ice Control uses to weld various models of light-duty and heavy-duty snow plow frames made of A36 mild steel.
Light-duty plows are available in 8 ft., 10 ft., 12 ft., and 14ft. lengths and heavy-duty plows come in 12 ft., 14 ft., 16 ft., 19 ft. and 22 ft. lengths. Longer frame lengths are not welded in the robot cell. These frames each require 175 to 200 welds. Most are single-pass welds that are 101.6 mm to 127 mm (4 in. to 5 in.) in length, and some require two passes and/or weaving.
The frame welding cell consists of two, extended-reach Motoman HP50-20 robots controlled by an NX100 DRC — dual robot controller — that is programmed using a single teach pendant.
This cell uses the same kind of welding equipment, peripherals and shielding gas as the first cell, and has two AC servo-controlled Motoman MHT-1600 headstock/tailstock positioners. The positioners feature a 3,000 kg (6,613.8-lb) rated load, 3.28-sec., 180-degree sweep, and 10.6 rpm headstock speed.
Drop pins or screw-down clamping bolts are used respectively to lock the positioner head- and tailstocks in place along manually adjustable mobile sub-bases (linear slides).
One pair of sub-bases is used for part lengths from 8 ft. to 19 ft., and the other pair is used for part lengths from 8 ft. to 22 ft.
Pin and bolt positions for each part length are numbered and color-coded for ease of operator use. This flexible approach permits the centerline of each part to be maintained in the same position, regardless of frame length. It also facilitates programming by allowing points to be taught on one side of the positioner and then shifted to the other side, as a mirror image, with only minor touch-up required.
Motoman also provided two sets of fixture receivers per headstock/tailstock positioner for a total of four bolt-on fixture adapters. Each positioner has one set for light-duty frames and another for heavy-duty frames. The operator bolts fixture adapters to parts off-line and uses an overhead crane to lift them into the headstock/tailstock fixture receivers.
Cell guarding also meets the ANSI/RIA 15.06-1999 safety standard, and includes 2.4 m. (8 ft.) safety fencing, one personnel gate, four sliding doors — two at each positioner load/unload station; arc flash protection curtains, and a three-color status beacon.
“We can weld about three frames a day manually and we wanted to make 10 per day on a 10-hour shift. The robot cell surpasses our goal. For example, it can weld 12-ft frames in 42 min. to 45 min. That's 25 percent to 30 percent faster than our requirement, with similar results for other frame sizes,” Sexton said.
“Weld quality with the robots in both cells is absolutely excellent. Now we have consistent high-quality, good-looking welds with the proper penetration every time. Consistent welding has led to better fit-up, too,” Sexton said.
“At first, our guys were afraid that robots were coming in to take their jobs, but they quickly realized that they were going to produce a lot more work. Now they are all vying for the chance to work with the robots,” Sexton said.
“Finding skilled manual welders isn't easy these days. We've had to bring in greenhorns that have never worked with iron before and train them in how to weld and do our process. Their welds don't all look the same. Now, with the Motoman robots, we get consistent welds that all look the same every time. It makes things a whole lot better.” Sexton said.
“Our guys have been working up to 16 hours a day, six days a week. Now that we can make moldboards and frames so much faster, we hope to get to one 10-hour shift per day, five days a week,” Sexton said.