North America's largest metal forming, fabricating, welding and finishing event heads to Orange County Convention Center in October 2024. FABTECH provides a convenient "one stop shop" venue where you can meet with world-class suppliers, see the latest industry products and developments, and find the tools to improve productivity, increase profits and discover new solutions to all of your metal forming, fabricating, welding and finishing needs.
North America's Largest Metal Forming, Fabricating, Welding and Finishing Event
Integrators can automate grinding processes to help achieve higher productivity and quality
By Thom Record, KUKA Robotics, Shelby Township, Mich.
Reprinted with permission: The AWS Welding Journal
“One of the things that we learned while we were talking to people on the floor at FABTECH 2019 is that nobody likes to do grinding, and nobody wants to do it,” said KUKA Senior Sales Application Engineer Pat Duda.
Indeed, falling into the three “D’s” of traditional manufacturing jobs — dirty, dull, and potentially dangerous — grinding is a demanding occupation that often presents workers with several ergonomic challenges.
Like other sectors of manufacturing, it is becoming more difficult to find workers with the skills and experience needed to successfully support grinding and finishing applications for welds.
One solution to this problem may be to use robots to automate part of the processes. While robotic welding is fairly established, few system integrators have the experience and knowledge required for success with robotic grinding and finishing applications.
“There are only a select few integrators that have deep expertise in both grinding and automation, and they are too busy to keep up with the market demand,” observed Scott Barnett, robotic application engineering manager, 3M.
Putting the Two Sides Together
Both KUKA and 3M heard from numerous frustrated customers and system integrators that had tried to tackle robotics on their own and found it to be too expensive and laden with a high risk of failure — Fig. 1. So the two companies worked together and developed a solution that could bridge the knowledge gap and better serve end users.
The result of the collaboration is KUKA ready2 grind, a preconfigured robotic grinding system that combines the necessary hardware, software, and assistance to better help system integrators implement their projects in a faster manner while also helping to reduce risk.
The system supports a wide range of fabricated metal parts, from racks and enclosures to trailers and nonsurgical medical devices.
Designed to handle a range of metals with different processing conditions (like stainless and carbon steel), the system works optimally on welds that have been applied robotically and have less variation.
“It’s also able to handle manual welds where there is more variation but the programming becomes more complex,” said Barnett. “Simpler geometries are always easier to work with.”
Greater Than the Sum of Its Parts
The strength of the system is that it blends the expertise and product knowledge of two experienced organizations into one solution, helping to reduce the risk associated with assembling various components together.
The system comes furnished with a KUKA KR 60 robot and preconfigured controller. The six-axis robot provides the high stiffness needed to compensate for process forces over long periods of time, especially at forces required by weld grinding applications.
“If you’re running something like a right angle fiber disc, the robot can run it at a much shallower angle than a person can because it can hold the tool rigidly. This means you will be using a lot bigger part of the abrasive, which can actually improve the life of the disc,” said Barnett.
Robotic weld grinding relies on consistent, long-lasting abrasive performance to meet finish requirements, but few integrators on the automation side have enough experience working with abrasives to choose the correct one for an application. To help them get started, the package includes a choice of starter kits designed for use on either carbon or stainless steel.
As important as each part is to the solution, the 3M™ Active Compliant Tool that attaches to the end of the robot is perhaps the most critical. The active compliance in the tool enables the system to apply a consistent force independent of the orientation of the tool while still maintaining contact with the part.
“It [the tool] adapts for variations in a part and programming, allowing the media to float in and out to adjust to the part. It really makes the programming a lot more forgiving and enables the system to work properly, even when the parts vary up to 10 mm,” said Duda.
The tool comes integrated with a 3M™ Servo Rotary Tool, which is equipped with a servo motor that maintains programmed speeds to optimize abrasive performance. The rotary tool also includes a built-in tool changing function for applications that require multiple abrasives, saving integrators the time of changing them manually.
Electric Tool Enables Maximum Performance
One of the most important parameters for running an optimum abrasive process is ensuring that the abrasive is operating at the right speed for the product.
Most pneumatic tools, under any reasonably applied force level, will reduce in speed. The tools tend to bog down, so their actual speed is typically less than the free running speed of the tool. That is not the case with an appropriately sized servo tool. If a person chooses to run it at 6000 rotations per minute (RPM), it will run at approximately 6000 RPM under typical forces that are applied, whereas a pneumatic tool may only run at half that speed under a reasonably applied force.
“The benefit of a rotary tool is that it is electric, as opposed to pneumatic hand tools, which are most commonly used by manual operators in our market. This means that the servo tool is able to retain speed much more effectively than pneumatic tools, which rely on air. This translates to, not only, longer abrasive life and less consumable cost, but also higher productivity via faster cycle times,” said Barnett.
Intuitive Human-Machine Interface Reduces Complexity
A big concern in any process for both integrators and end users alike is programming complexity. For an application like automated grinding, where there is often little experience, ease of use becomes even more critical to ensuring a successful adoption.
The system’s intuitive user interface was designed to focus on the most important parameters of an abrasive application in a simplified way, enabling the integrator or operator to concentrate on the abrasive process parameters.
“Rather than worrying about [hardware] inputs and outputs or anything that low level, they can turn their attention to things like what force they want to use or what RPM they want the tool to operate at,” said Duda.
From an integrator perspective, they receive feedback as to how the system is performing. If they need to adjust a setting, they have the visible information in the palm of their hand to know what needs to change. For the end user, it provides the peace of mind of knowing that their operators will have the ability to manage the process over time after it’s been implemented.
Saving Time and Minimizing Risk
Given the complications of the process and lack of industry experience in handling both disciplines at once, 3M and KUKA worked together with a number of their integrator partners to develop a community that supports manufacturers that want to implement the system.
As part of the package, integrators receive proof-of-concept engineering support, where they can send parts to 3M’s Customer Abrasive Methods Center in St. Paul, Minn., to obtain recommendations for attaining an optimal abrasive process for their application. This helps save time and expense in finding the right mix of abrasive and process parameters, and provides the confidence of knowing it’s being done right.
“In many cases, people that are less familiar with these processes will simply look to replace a human arm with a robot arm without considering all of the benefits that a robot can bring to the application. When we help a customer, we look less at what they are currently doing and more at what they want to achieve from a results standpoint,” said Barnett.
In addition, customers have access to the integrators that both companies work with, as well as KUKA’s on-call services.
While the collaboration is still in its early stages, the community that both organizations have created with some of their integrators continues to grow. Many integrators took part in the first Robotic Grinding and Finishing Conference hosted by the Robotics Industries Association last year and are looking forward to this year’s event on April 27 and 28 in St. Paul, Minn.
“A lot of the people that come to the event have automation experience and others are more familiar with grinding processes,” concluded Duda. “So, this is the perfect environment for everyone to come together and share ideas as to how we can collaborate.”
Fig. 1 —For system integrators with limited experience in abrasive applications, there can be a lot of trial and error that can potentially waste both time and money.
FABTECH 2024
About the Expo
North America's largest metal forming, fabricating, welding and finishing event heads to Orange County Convention Center in October 2024. FABTECH provides a convenient "one stop shop" venue where you can meet with world-class suppliers, see the latest industry products and developments, and find the tools to improve productivity, increase profits and discover new solutions to all of your metal forming, fabricating, welding and finishing needs.
