Both multiprocess robotic systems meet all project goals and objectives and improve productivity by automating material handling, plasma cutting and welding operations. Systems achieve aggressive process cycle time of 2 minutes for pipes with 5 holes and 4.5 minutes for pipes with 18 holes. Direct labor was significantly reduced by two to three (hard-to-find) skilled welders per system to part-time tending by an operator from an upstream robotic cell. Robotic systems meet customer’s quality objectives of 99.8% good welds.
Project Challenges
- Fully automate multiple processes. Handle and properly orient individual pipes (10 part numbers). Plasma cut holes into carbon steel irrigation pipes and then weld couplings onto each pipe. Pipes are 13.7-m (45') L and weigh about 204.1 kg (450 lbs.) each. Each pipe requires 5 or 18 holes that are 19.05 mm (0.75") in diameter. Number of holes and spacing varies, depending on part number.
- Process individual pipes with 5 couplings in approximately 2 minutes and pipes with 18 couplings in 4.5 minutes.
- Fully automate handling, hole-cutting and coupler welding processes and improve productivity and quality, while reducing the need for scarce skilled welders.
Motoman Robotics Solution
Motoman Robotics provided two identical five-robot multiprocess systems to plasma cut holes and weld couplings in irrigation pipes, as well as handle pipes between stations. Each custom system includes:
- (3) Motoman HP50-35 robots with NX100 TR3C controller.
- (2) Motoman HP200 robots with NX100 DR2C controller.
- (3) Miller Auto-Axcess 450-Amp weld packages with air-cooled torches.
- (3) Reamer/sprayer nozzle cleaning stations with automatic wire cutters.
- (3) Hypertherm Powermax 1650 100-Amp power supplies and plasma cutting torch packages.
- (3) Individual stations for pipe search/orientation, pipe regrip and welding.
- End stop – locates and orients flange on one end.
- Vibratory bowl feeder - for couplers.
- Coupling conveyor with singulator.
- (3) Custom HP50-35 end-of-arm tools – multifunction grippers.
- (2) Custom HP200 end-of-arm tools for pipe handling/orientation.
- Cell guarding package, including 2.44-m (8') H wire mesh perimeter safety fence, two safety-interlocked access gates, and arc flash protection curtains.
Fixtures/Tooling Details
Motoman Robotics provided custom end-of-arm tooling with clamping fixtures. The two HP200 robots use pneumatic 3-jaw mechanical (I.D.) grippers to handle pipes by their ends. Multifunction grippers on the three HP50-35 robots use two fingers to pick up a plasma cutting torch and cut holes in the pipe. The same fingers also pick up couplers and hold them in place for tack welding by the integrated welding torch. The handling portion of the EOAT pivots out of the way for the finish welding process.
Ref: ACS-119