Robotic Welding: How Robots Can Help Automate Welding Tasks
A welding robot is any automated machine that is operating in a welding application. Robots and welding have a long history. It’s no wonder then that robotic welding applications often have a strong return on investment. There are often many integrators and manufacturers that specialize in robotic welding.
The purpose of this article is to explore the basics of robotic welding and its advantages. This will help you gain a starting point in automating some of your processes.
In this article:
- Industries for robotic welding
- Robotic welding types
- Why automate the welding process?
- Robot types used for welding
- Additional considerations
Industries For Robotic Welding
Ideally, robots can weld in any industry that has welding applications. The most common industries for robotic welders are:
Companies in these industries often find great success with robotic welding. The reason for this is the types of products these companies make lend themselves easily to automation. In a previous article, we discussed the characteristics of tasks that are ideal for robots. You can read more about that topic here: Industrial Robots: The #1 Guide to Robotics for All Industries.
For example, the automotive industry is a heavy user of welding robots. Automotive welding processes have the following characteristics:
- Perform the same weld repeatedly
- Small variation of parts to weld
- Process has inherent dangers
- Requires high levels of repeatability and accuracy
- Needs high throughput
It’s clear why the first robot was used in an automotive welding application!
There are several different types of welding. Naturally, you may wonder which welding types robots can do. Robots can typically perform any type of welding process. This includes:
- Spot welding
- Arc welding
- Resistance welding
- MIG welding
- TIG welding
- Laser welding
- Plasma welding
Spot welding is a type of resistance welding that joins two pieces of metal together at a single spot. Hence, the name “spot welding”. This process uses large amounts of electrical current through the metal to create immense amounts of heat. This heat melts the metal allowing two sheets to join together.
Arc welding is an old yet very common form of welding. As the name suggests, arc welding uses an electrical arc to weld metal together. Like spot welding, electricity is the catalyst for this process. A current passes through a metal stick to the material. The metal stick is referred to as an electrode. The current appears as a bright arc. This arc provides the heat necessary to melt the two pieces of metal together.
Resistance welding is a broader term for several types of welding. This includes any weld where electric current is passed via direct contact through two pieces of metal to weld them together. Spot welding is one type of resistance welding. Other types include projection welding and seam welding.
MIG welding is a type of arc welding. MIG stands for metal inert gas. It is often preferred for its speed and versatility with different kinds of metals. MIG welding is also common for robotic welding applications. An additional component of MIG welding is the use of a shielding gas. This gas protects the welding process from contaminants that may be in the immediate atmosphere.
TIG welding is another type of arc welding. TIG stands for tungsten inert gas. This process uses a tungsten electrode to create its arc. Like MIG welding, this type also utilizes gas for contamination protection. TIG welding is a notoriously difficult type for operators to master. It is also not as fast as other comparable welding types. What it loses in speed it gains in a more focused, often stronger weld.
Laser welding utilizes a high-powered laser beam to create small and focused welds. This style allows for unparalleled control making it useful for both metal and plastic welding. Laser welding systems include fiber, gas, and solid-state types. These systems offer some of the highest speed and accuracy rates achievable for the welding industry. However, you should expect laser welding systems to be some of the most expensive options on the welding market.
Plasma welding is similar to TIG welding and sometimes even uses a tungsten electrode. It differs mostly in the construction of the torch. The torch has a small copper nozzle that ejects the arc at high velocity and temperature. This is where the advantage of plasma welding lies. Standard arc temperatures for plasma welding can be in the 25,000 °C to 30,000 °C range. Comparatively, standard temperatures for other arc welding types can be in the 5,000 °C to 6,000 °C range.
There are plenty of factors that drive companies to automate the welding process. Huge returns are found moving from manual to automated welding. Common reasons include:
- Cycle time improvements
- Labor costs and availability
- Material Efficiency
Cycle time is often an immediate concern for high-volume welding processes. Applications that require high levels of throughput sometimes find operator speed to be the limiting factor in manufacturing. In other words, manual welders have limits in welding speed that can negatively impact manufacturers. Robots can weld at a higher rate than even skilled human welders. This speed is found not only during the welding process itself but also in the time needed to move between positions. Additionally, robots do not need breaks or experience downtime due to shift change. A robotic welder can continue welding as long as the material is available to it. These factors often lead to the most noticeable return on investment for manufacturers.
What could your return look like? Our Investment Calculator can help you estimate savings and identify areas of improvement, and calculate your return on investment.
Labor Costs and Accuracy
Skilled welders are an expensive and limited commodity in today’s labor market. This puts manufacturers in a difficult position to maintain operations. Skill differences lead to noticeable quality differences in welding which has a negative impact on sales. Furthermore, labor costs are a considerable impact on a manufacturer’s bottom line. For this reason, many companies find automating the welding process to be a necessary decision to remain competitive.
Quality control is essential for welding applications. Small imperfections and inconsistencies cause voids, warping, and weaknesses in welds. Issues like these can even make the product unusable. This leads to more scrap and wasted material. Most manufacturers track the amount of wasted material every year. This cost can be recouped with the integration of a welding robot into your process. The consistency of robotics means the same weld quality each time and less scrap compared to manual welding.
For certain applications, extreme precision is required. This level of performance is only achievable through automating the welding process. The high-resolution feedback provided by the servo motors on the robots allows for precision that can’t be matched by human welders. This precision is attainable time and time again since the robot won’t get fatigued like manual welders either.
Robotic welders are more efficient with the use of material. Since they follow a programmed set of instructions, robots will use the same amount of material each time they weld a part. Even skilled welders will make mistakes and have inconsistencies. There are variations in the amount of welding material consumed from part to part in the manual process. These materials include electrodes, plasma, gasses, etc.
The welding process is an inherently dangerous one. These dangers include:
- Electrical shock
- Arc exposure
- Explosive hazards
Any process that includes high-voltage electricity and high temperatures will be dangerous for humans. Manual welders are always exposed to these hazards during the welding process. Potential injuries include:
- Hearing loss
Workplace injuries are expensive. This expense is mitigated with the use of robotic welders. It is important to remember robots do not remove the danger from the process. Robots simply remove a human operator from direct exposure to the process. You should follow proper safety protocols and risk mitigation strategies when integrating a robot welder in your facility.
Technically, any type of stationary robot can be used in a welding application. These robot types include:
Any of these robots can be a welder if a welding tool can be mounted to the end of its arm. However, six-axis types are by far the most common type of welding robots. The reason for this is that they are the most flexible robot type. The six-axis robot can contort itself to weld at angles not achievable by the other robot types. This robot can also scale to have a large range of motion required for many welding applications.
A recent innovation in the robotic welding industry is the inclusion of collaborative six-axis robots for welding. Collaborative robots are easier to teach new processes to than standard industrial robots. The teaching process is often done with a hand-guiding technique. An operator can guide the robot through the process by hand to teach it a new part to weld. This gives robotics a place for medium-volume applications. Standard industrial robots require new code to be written to teach a new part. This might require a specialist to spend several hours to days to develop and test the code. An operator might teach a cobot a new part in a matter of minutes.
An important note here is that collaborative welding robots have limitations. Factors such as size, speed, and payload capacity mean collaborative robots won’t be right for all welding applications. It is important to consider the specific requirements of your application to determine if a collaborative robot is the right solution for your welding robot. An expert can help you make this determination. HowToRobot’s network of independent advisors can help you determine where and how to automate.
There are additional considerations that you must account for with robotic welders. Rarely can a robot be introduced into a process without additional equipment. Robots may also not work in every welding application. For these reasons, it’s important to identify experienced suppliers.
Ask suppliers for solutions here with our RFI tool. They will answer you how they can automate your process quickly and easily.
Additional equipment can include jigs and safety systems. A jig is a mechanical system that holds and presents the parts to be welded to the robot in a predictable way. Jigs can be things like rotary tables or clamping systems depending on the application. Jigs can also be considerably expensive. For this reason, it is important to think about how the part will be presented to the robot for your welding process.
As with any robot, safety equipment must be included in the overall cost of the project. Safety equipment might include:
- Safety cages
- Light curtains
- Safety scanners
- Safety relays
The welding process has additional hazards that make safety even more important to consider. Robots are designed to automatically perform its task repeatedly. Safety systems ensure that if any human operators or obstructions are present the robot will behave in a safe and predictable way.
When Are Welding Robots a Bad Idea?
There are certain scenarios where robots may not be beneficial for your application. Certain processes may vary too much in the product type used. For example, consider a business that produces many custom parts in small volumes. This business may find itself reprogramming a robot many times per year. This added cost and downtime may make a robot inefficient for this process.
Other risks include dependencies on robots in certain applications. If a single robot failure can hold up an entire process you might expose yourself to risk. For this reason, it is important to have preventative maintenance measures and spare parts in place.
You can browse our supplier directory to find companies near you that specialize in your application or brand of robot. Our directory of more than 15,000 suppliers can help you get connected with companies relevant to you quickly and easily.
It is important to remember that robotic welding systems require a hefty up-front investment. This leads to a high barrier of entry to the robotic welding market for some manufacturers. You can use HowToRobot’s RFQ tool to receive quotes and offers from robot suppliers based on your needs to see what your costs could be.