In the first installment of this article, we explored some of the reasons shop owners may want to consider automation, including growing shortages of skilled labor, increasing pressure for
consistent weld quality and competitive pressures from both overseas and domestic rivals. This second installment delves into how collaborative robots, in particular, can solve some of these challenges. The meteoric rise in collaborative robot sales proves that a growing number of owners are already onto the benefits they provide.
Collaborative robots, better known as cobots, are a game changer for manufacturing automation. For the high-mix, low-volume machining and welding job shop, cobots will frequently prove to be the automation solution of choice.
Cobots vs. industrial robots
So, what’s all the fuss about? Robots entered the factory floor more than 50 years ago. A modern automotive assembly line consists of scores or even hundreds of hulking robotic arms, some weighing tons and capable of lifting as much as 5,000 lbs. The cost of a fully equipped automated weld cell might range from around $100,000 to much higher, including the cost of a newly minted robot, end effectors, digital control systems, safety enclosures and more.
Job setup for an industrial system requires complex programming, precisely mapping every movement the robot will need to make to accomplish a specific task. Certainly, for many applications, an industrial robot system will be the only option due to factors such as payload and reach requirements for welding larger assemblies. In the right situation, particularly one where a standard part is welded day in and day out, such expense can be easily justified.
However, there are many drawbacks to the use of industrial robots beyond cost, safety and fixed space utilization. By far, the most important drawback – especially in high-mix, low-volume environments – is a lack of flexibility. Reprogramming is often not feasible to support a fast-changing order flow.
Cobots, however, are designed to address that challenge with pad-based setup capabilities that require neither programmers nor trained welders. Much of the accumulated knowledge of the welding trade is built into the software. Setting up a job can be as easy as inputting the start points, the characteristics of the material to be welded and the appropriate welding wire for the job. Instruct the system to weld a line (or arc) between the points and the software does the rest.
While this may not always be efficient for an order size of one, the savings quickly multiply with the job size. Once the job is programmed and fixtured, the cobot will weld each part identically. Those coming offline at 3:30 p.m. will be identical to the fresh welds at 9:30 a.m. And the cobot doesn’t need bio breaks nor will it arrive at work Monday morning groggy from watching the Sunday night game with its buddies.
Far from replacing skilled welders, a cobot’s best role is as a people extender. It works safely in proximity to humans. More important, the cobot is happy to take the hot, dirty and dangerous job, freeing the best welders to focus on the more complex, difficult and often more profitable jobs while the cobot addresses routine production in the corner.
Getting started with cobots
Stu Shepherd has led the U.S. operations of some of the global players in robotic automation. Shepherd joined Universal Robots (UR) in 2018 and is currently vertical development director for the Americas, focusing on the automation of precision metalworking. Since Shepherd joined UR, the company has experienced phenomenal growth, most recently reporting a 50 percent increase in sales for the first three quarters of 2021 versus 2020. The transformation of welding through cobot automation plays a big role in achieving these results.
“Collaborative welding robots are the first truly disruptive technology to hit robotic arc welding in decades,” Shepherd says.
UR has designed its product to be simple enough for a smart manufacturing team to deploy its first cobot out of the box. At Fabtech 2021 in Chicago, the UR booth provided hands-on proof; prospective customers who’d never touched a robot were handed a controller and within minutes were programming their first welding operation on the floor.
Over the past few years, Shepherd has worked to develop UR’s network of more than 60 automation distributors and integrators to support customers. These firms offer perspective not just on the how-to of automation, but can also provide perspective on the possibilities presented by the rapidly expanding capabilities and ease-of-use now being offered.
Shepherd’s advice is to work with one of these welding automation specialists to leverage their experience and speed solution implementation, saying “you don’t need to figure it all out at the beginning. Get started and find a simple task that can readily benefit from automation. Cobots are best when they are replacing humans in the dull, hot, dangerous and dirty jobs that humans don’t want. Then, begin to work with your automation partner to find other places within the shop that can benefit from automation.”
This advice is made easier by the recent trend toward cobots as a service and short-term rental as options for deployment. If a shop isn’t sure that automation is going to work, a three-month test-run cobot deployment won’t break the bank.
It’s not just cobots
Tom Richardson, technical specialist with Arc Systems, an integrator focused on welding automation, works with a variety of manufacturers that incorporate welding in their operations.
Arc Systems is based in Houston where many of its customers weld big iron for industries like drilling and petrochemicals and the projects call for industrial robots suited for larger scale projects.
Richardson’s customers are finding an increasing need for automation. He points out that advances in welding software have made industrial robot automation far more accessible to industries that previously relied exclusively on human welders.
For a shop just getting started in automation, Richardson says, “most integrators will be open to an introductory call to explore a prospect’s needs. Having worked on numerous automation projects in a variety of industries, an experienced integrator can point out opportunities for automation that the shop owner may not be aware are possible.”
Many processes that a robot couldn’t have handled 10 years ago can now be automated. Grinding is a good example. Moreover, once programmed for each weld, the robot will produce its best work hour by hour and day after day.
Whether it’s an industrial robot or a cobot, Richardson points out that welding efficiency is limited by physics. The robot may not be able to put down material faster than a human welder. But the robot can do the repetitive jobs, leaving the tough welds to the humans.
Recently, Arc Systems was approached by a barbecue pit manufacturer that hoped to automate a task that turned out to be too complex for a robot due to the geometries involved. In reviewing the project, Arc Systems noted some simpler tasks that could be readily automated. This freed up the experienced welders to focus on the harder welds, dramatically improving overall productivity with more product consistency.
What to automate?
UR’s Shepherd indicates that welding automation can reduce operating costs by enabling skilled welders to set up orders and tend to multiple welding jobs rather than just doing repetitive welding tasks. Skilled labor productivity and equipment arc-on times can be increased by 50 percent or more. With only a few minutes of training, many cobot welding jobs may be tended by general labor, which further frees up skilled welders and reduces costs.
For skilled and general labor, use of cobot welding is new and fun plus it reduces work-related fatigue and exposure to heat and fumes, which may reduce turnover and extend employee longevity. With the right products selected, automation can enable second (or even third) shift lights-out production or minimal staffing operations for more standard products, taking equipment utilization from 30 to 60 percent or even more. This leaves the more complex tasks to the primary daytime shifts preferred by humans. Such increases in equipment utilization are more and more critical for shops faced with overseas competitors operating 24/7.
Joe Crawford is vice president of engineering at H3 Mfg. Group LLC, which has three plants in Illinois where workforce efficiency is critical. Prior to joining H3, Crawford spent 10 years assisting customers with implementing shop automation projects. He emphasizes the need to start with a holistic look at the automation puzzle with the goal of maximizing overall equipment uptime. Crawford suggests starting with a hard look at the parts being produced. Look for opportunities to automate 50 or 60 parts, not just five or six.
Crawford suggests that a good automation customer needs to be open minded. They shouldn’t start by looking at automation equipment, but with the processes and parts to look for commonalities where repetitive tasks apply to multiple parts. Once the automation opportunity has been identified, they can pick the best equipment to address the problem. Sometimes the solution requires a rethinking of the process, perhaps redesigning the fixturing to support an automated approach versus the former human-driven approach. Sometimes the appropriate automation solution won’t even be a robot.
Arc Systems’ Richardson adds that for the best results, the automation customer should be able to define their expectations from the process. If AS9100 compliance is mission critical, will process automation aid that goal by guaranteeing consistent quality over tens of thousands of welds? Customers should apply the 80/20 rule. If 80 percent of what they do is subject to automation, they should focus there and leave the 20 percent for skilled and experienced welders. The welders will appreciate the opportunity to step up their personal game and the customer will benefit from the improved margins and the higher revenue the robots make possible.
