The market for automated welding is steadily growing across the world, and Europe has an excellent tradition both in terms of construction and integration of automation systems in production plants. The sectors that absorb the most production and use of industrial robots are: automotive, electronics, metals, and plastics.  The inclusion of automated islands in the industrial context has changed the production cycle of many companies, increasing the quality of products and the speed of processing, thereby cutting costs and reducing safety risks for operators.

Welding and Automation : how are we doing?

The Metal sector has shown considerable interest in technological innovation in terms of increasing production and use of automation. This has led to a dynamic trend in all markets, with a high percentage of robot sales and automated systems. Indeed, annuel root consumption increases by 12~22% compared to the previous year.

It is recognized that automated welding produces high quality and repeatable joints while reducing heat production, slags and, wastes during the process. The use of a welding robot avoids oversized joints, since the systems are programmed with parameters that allow to joint production with precise dimensional characteristics, avoiding expansion or contraction processes in the surrounding metal during heating and cooling cycles.

Automated systems guarantee high reproducibility and shorter cycle times in welding processes, reducing the consumption of resources and electricity compared to manual processes, thus meeting the growing need for energy efficiency. The speed of the machines is about five times higher than the average man, not to mention that the robot can move quickly from one joint to the next, allowing the execution of several operations in series.

Automation reduces labour costs and compensates for the shortage of skilled welders, as less practice is required. Therefore, the welder becomes a process monitoring operator.

Flexibility also extends to the variety of process types and joints that can be manufactured based on a variety of materials and components. Generally speaking, the robotic stations are equipped with a repository with various welding programs that can be used on different materials and thicknesses, for example MIG, MAG and TIG. Here it is possible to install standard robots, hollow wrist robots, robots with push-pull torch or with master-slave system.

Cobotized welding

In particular, it is worth mentioning how welding benefits considerably from the use of collaborative robots (cobots), which carry out the tasks alongside the operators in the assembly lines. Cobots estimates indicate average annual growth of more than 50% until 2026. While large companies are mainly interested in installing fast-working robots in their production lines in order to maximize productivity, the cobots are more suited to the needs of small and medium-sized companies. They are slower and more flexible since they have to learn, repeat, and save movements to be carried out from the operator. In essence, the robotic arm is able to replicate, the work that a highly qualified welder would do with greater quality and in less time, implying additional health and safety benefits.

Welding requires repetitive and precise torch movements. As such, the welder’s fatigue is not an inconsiderable problem. This physical condition can lead to musculoskeletal disorders. By placing a robotic arm next to the human, fatigue is drastically reduced as the torch is manipulated by the cobot. The welders are only required to monitor the process and guide the torch where necessary. The ergonomics of the working environment is considerably improved, since the use of robots allows to avoid welding in forced positions. This prevents stress to the operator’s body and limbs experienced during manual work and risky for their health.

Carrying out the operation with the help of a robot protects the operators’ health, preventing them from being exposed to the UV/IR light generated by arc welding, which can cause visual disorders, as well as long-term carcinogenic pathologies generated by continuous exposure to smoke and toxic gases. In particular, the use of collaborative robots allows better control of emissions, thereby reducing the environmental impact.

There are considerable benefits in terms of joint quality, since the use of a robotic arm guarantees a defect rate of less than 3%, avoiding additional work processes. It is not necessary for the operator to act manually to file or roughen the beads released from the welding material or to repeat the work, using a gas torch if any defects have to be eliminated. The cobots’ precision combined with optimized welding power avoids the use of additional welding wire which causes energy and material waste. By reducing the quantity of defects and using adequate power, the use of a cobot allows to considerably reduce the consumption of gas to maintain the flame active. CO2 emissions into the environment are lower. In this regard, it should be noted that welding accounts for 4.5% of the European Union’s gross energy consumption, and arc welding produces 9.82 grams of CO2 per second.