Welding Automation Delivers Benefits to Manufacturers Large and Small

There is a global shortage of skilled welders, and that gap is only going to increase.  Welding is difficult work, often repetitive and dull, with constant exposure to fumes and arc flash.  Awkward postures and repetitive motions carry the risk of injuries, and the need to maintain a constant focus on the weld bead wears down even the most experienced welders.

It’s no wonder recruiting younger generations into welding is a challenge, throughout the Americas, Europe and Asia.  Projections call for an additional 1,000,000+ welders in the next 25 years, and the immediate shortages in the US alone are 85,000.  And the shortage will only accelerate in the coming years, as the average welder is within 10 years of retirement.

The shortage of skilled welders has an immediate impact on shops of all sizes, the most obvious being production bottlenecks.  Fab shops are struggling to keep up with the production needs of their current customers, putting those relationships at risk.  In many cases, the end customer has no choice but to bring on a second supplier to ensure a steady supply of weldments.  For in-house welding production, total production volumes of finished products can be impacted, limiting top line sales.  And for shops struggling to keep up with demand from their current customers, internal or external, there is no welding capacity to bring on new customers and grow the business.

A common response to the welder shortage is to schedule more overtime to increase production volumes.  While this approach can be effective in the short term, it is very difficult to sustain over weeks and months.  This topic was first studied in 1947 by the US Department of Labor investigating defense production at the end of WWII.  They found a drop in productivity as overtime hours increased, from an 8% drop at 50 hours to a 22% drop at 70 hours.  In a 2020 study, John Pencavel from Stanford University found a 10% increase in OT hours dropped overall productivity by 2.4%, and at hours over 55 per week, the productivity drop was 24%.  This was futher confirmed in a study by J. Nevision from OAK Associates, who found a 25% drop in productivity at 60 hours per week.

The reductions in productivity are just the tip of the iceberg, as mental health, family stability, worker safety, job satisfaction and turnover all suffered at higher levels of overtime.  The total cost in this competitive labor market is significant.

Higher Productivity Please

With no immediate solution to the welder shortage in sight, the challenge is to boost productivity and output with the existing manufacturing team.  And that’s where robotic welding comes in.

Automation investments to boost productivity are not new – arc welding robots have been on the market since the late 1970’s.  But the traditional robot approach to automated welding has very real limitations, including

• Floor space – safety guarding required by traditional automation consumes large chunks of manufacturing floor space.
• Complexity – traditional robots are difficult to program, operate and maintain.  Small shops just don’t have the skilled resources to dedicate to traditional automation, and large shops don’t want the expense.
• Lead times – traditional automation lead times are typically 3-5 months, an eternity for a shop fighting labor challenges day to day.
• Limited flexibility – traditional robots are difficult to move to a new location, and to re-program for new parts, limiting the overall efficiency.
• Total cost – given all the above points, traditional robot welding is an expensive investment that is difficult to justify.

Which brings us to collaborative robot welding, which first hit the market in late 2018.  Cobot welding has significant advantages over traditional robotic welding:

• Floor space is not an issue.  With a proper risk assessment and operator PPE, cobot welders can be deployed throughout manual weld lines with no safety fences, interlock or barriers.  Quite often cobot welders can utilize existing tooling and fixturing.
• UR based cobot welding solutions can be programmed and operated by welders, not robot engineers.
• Long lead times are in the past.  UR cobot welding solutions can be in production in weeks, not months.  PO to Production in 3 or 4 weeks is common.
• Simple programming delivers maximum flexibility.  The old adage “I can weld it before you can program it” is no more.  New parts can be programmed in minutes, maximizing flexibility.
• Total cost is typically 1/3 to ½ that of traditional automation.  And with short lead times, UR cobot welding solutions deliver ROI in record time.

Boosting productivity with cobot welding is all about leveraging the skilled welders on staff.  The most common configuration is 1 experienced welder operating 1 cobot welding system.  The experienced welder programs the cobot and welding variables, fixtures up components in station 1 while the cobot welding system is arc-on in station 2, and ensures quality welds after the cycle.  Arc on time is maximized, and the skilled welder is removed from the fumes and arc flash.  This configuration can effectively double the output of a skilled welder, and with the proper set up with multiple fixtures, welding can continue at breaks, lunch and end of shift for even larger gains.

Depending on the part mix and weld specifications, one skilled welder can operate 2 or 3 cobot welding systems.  And for larger weldments, the cobot and the skilled welder can work on same part, although this configuration requires a careful risk assessment and proper PPE.

Cobot dexterity can also contribute to increase productivity.  Manual welding requires line-of-sight to the weld path, and manual repositioning of the part (or the skilled welder), reducing arc-on time and in many cases effectively doubling cycle times.  Automated welding can reach around, over and through to bring the torch to the weld path, shrinking part cycle times and increasing throughput.

Cobot welding systems can also deliver faster cycle times simply based on their ability to precisely follow a path as speeds faster than a manual welding can maintain.  In the case of MIG or TIG welding, the cobot speed may allow weld process adjustments to reduce cycle times.  In the case of laser welding, the cobot may be the enabler, allowing higher power output and shorter cycle times on thin gauge metals.

Improved Quality = Higher Productivity

Productivity is measured net of scrap and rework, so improving quality directly impacts the overall throughput of the shop.  The rigid control of weld parameters and torch angle and location will reduce scrap and rejects.  The addition of vision, laser and through-the-arc sensing can even maintain control on parts with inconsistent or poor fit-up.  While cobot welding solutions will improve quality on any parts, it is surprisingly effective with small, higher volume repetitive parts.  Shop managers have reported a fall off in quality late in a shift, as even skilled welders lose focus and concentration after welding hundreds of simple parts.  In many cases, the small, simple repetitive parts are the best starting point for a cobot welding solution, and can be loaded and unloaded by a machine operator rather than a welder.  As an added benefit, automating the repetitive parts frees up the skilled welder to work on more complex, higher value parts.

More on Labor

Part of the labor challenge in welding is not just hiring – it is also critical to increase job satisfaction for current employees.  Automating the Dull Dirty and Dangerous increases safety, reduces insurance compensation claims and increases employee job satisfaction.  When those very same benefits are recognized by prospective employees, the hiring process is far easier.

Low risk, rapid deployment cobot welding solutions from Universal Robots and our partners – download our Guide to Cobot Welding today to see how we can solve your business challenges.