On Mfg/Feb. 2016

High-Payload Industrial Robot

If you’re looking for a high-payload industrial robot, know that ABB, which has been making industrial robots for about as long as industrial robots have existed, has introduced its highest-payload unit, the IRB 8700.

How strong is it? It can handle up to 800 kg (or 1,000 kg with the wrist down).

But it isn’t just about being able to pick up heavy objects. It is also about being able to move them some distance, too. The IRB 8700 has a reach of 3.5 meters with the 800 kg on the arm.

Or, as John Bubnikovich, vice president, sales and marketing, ABB Robotics North America, puts it, "When designing the IRB 8700, we focused on combining ABB’s largest ever model with an unusually long reach for a robot in the high payload class.”

He adds, “Utilizing ABB’s superior motion control technology at high moments of inertia, the new robot automatically adapts and adjusts its speed to accommodate heavy and wide parts. With a compact footprint, optimized counterweight, parallel linkages, stiff axes and fewer drive motors, the IRB 8700 keeps its momentum down and speed up, providing unmatched agility and performance.”

There is simplicity and reliability designed into the robot. For example, there is one motor and one gear per axis rather than two, as can be found in other robots of this size. Counterbalancing is achieved through a counterweight and mechanical springs rather than gas springs.

ABB claims that the robot is 25 percent faster than robots in this heavy-weight category. There are two configurations of the IRB 8700, one with the 800-kg payload/3.5-meter reach and another with a 550-kg payload but a 4.2-meter reach. Either way, there is a high moment of inertia of 725 kgm². 

Both types are available with a dressing package called “LeanID” that ABB says means easier programming, reduced wear and a smaller footprint. abb.com/robotics

Improving Milling Operations

Sandvik Coromant has added new tools to its CoroMill lineup.  The Plura HFS—that’s as in “high feed side milling”—end mills are specifically tailored for machining steel and stainless steel—but can even be applied to difficult-to-machine materials like titanium, should the need arise. An interesting aspect of the tool is that it was designed taking modern milling strategies in mind. That is, many operations are using trochoidal milling approaches, which means that there is a constant maximum chip thickness and a short arc of contact, which results in high feed rates, minimal vibration, and long tool life. So the CoroMill Plura HFS is designed so that the complete cutting length of the end mill is used, thereby achieving a higher metal removal rate with smaller diameters compared to indexable milling. The tool has an unequal helix flue design, an asymmetrical chip-breaker profile, and a conical core shape with a smaller core diameter at the face and a larger core diameter at depth of cut maximum, all of which contribute to better machining (as in chatter reduction, increased material removal, and chip evacuation). The grade used is GC1740, which is formulated to resist bending forces during machining.

In addition to which, Sandvik has developed an eight-edge finishing tool for face milling, the CoroMill 425.  It is said to be ideal for applications including cylinder blocks, axle housings, brake carriers, and crankcases made from a variety of materials including compacted graphite iron. The tool can be used for dry milling—with GC1010 PVD inserts—or wet milling—with K20W grade inserts. There is a patented setting system for precise, reliable insert positioning to make tool setup simple.
sandvik.coromant.com/en-us/industrysolutions/automotive

Flexible Gear Shaping Machine

The model 100-SZ CNC Gear Shaping Machine available from Koepfer America is said to have the kind of flexibility and versatility that makes it well suited to job-shop applications. It features a compact design to minimize floor space. The machine handles workpiece diameters up to 120 mm external and 150 mm internal. It operates at up to 2,000 strokes per minute and offers a 100-mm stroke length. It has a 17-kW cutter spindle motor. There is a direct-drive torque motor work table. A cast iron shaping head and column provide superior vibration damping characteristics. The gear shaping machine includes a standard movable saddle, which means that combined with the comparatively long stroke, a wide range of fixturing solutions are possible. The machine is equipped with a Fanuc 31i CNC. 
koepferamerica.com