How Robotic Welding Supervisors Can Improve the Operation

Gaining a good return on investment (ROI) from a robotic welding system doesn’t happen by chance. It’s a matter of optimizing the robot and the robotic welding cell to operate at peak efficiency. And while this task is a team effort, it is led by the robotic welding supervisor.

So, what can the supervisor do to guide the way, while looking at more advanced considerations? Pay close attention and collaborate.

Find opportunities for improvement

Even if a robotic welding system is meeting production and quality requirements, it’s important that robotic welding supervisors commit to a continuous improvement process. Regularly looking for ways to increase efficiencies could provide the ability to produce more parts. It can also help identify issues within the robotic welding cell before they become problematic and cause downtime.

Robotic supervisors should pay close attention to details such as cable and consumable management, parts handling and workflow to pinpoint areas that could be streamlined. The goal is to avoid settling for less than optimal work practices to realize the full potential of the system. Doing so can provide companies with higher productivity and profitability and can set them apart from their competitors.

Rely on available resources

While the robotic welding supervisor may oversee the overall health of a robotic welding cell, the robot operator works hands on with the system daily to load and unload parts. For this reason, they are an excellent resource to rely on for insight into potential or existing problems, such as:

• Excessive spatter
• Poor joint configurations, or
• The need for tooling adjustments

Quality technicians are another internal resource to help the robotic welding supervisor identify any issues and drive performance improvements. In conjunction with welding engineers, they can help rectify issues like overwelding or part distortion.

External sources, such as a robotic welding integrator or equipment manufacturer, can help troubleshoot and offer advice to gain efficiencies. In many cases, they can also offer ongoing training that helps everyone improve their interaction with the robotic welding cell.

This article is the second in a two-part series focused on key information welding supervisors should know to help ensure robotic welding success. Read article one, Best Practices for Robotic Welding Supervisors. 

Best Practices for Robotic Welding Supervisors

With careful planning and attention to detail, companies that invest in a robotic welding system can gain advantages, such as:

• Increased productivity
• High weld quality
• Cost saving
• Parts consistency

The welding supervisor managing the robotic welding cell plays a key role in achieving these results — and with some best practices in mind, can help ensure long-term success. There are some basics that provide a good starting point.

Understand the robotic welding system
To maximize uptime in a robotic welding system, welding supervisors need to look beyond the administrative and operational duties often involved with this position and consider the actual components in the system. Maintenance personnel can often help.

It’s important for welding supervisors to understand how to quickly troubleshoot issues and how to adjust the weld programs, as needed.

Having a solid understanding of the functions of the robotic welding gun, welding consumables, power cables, and their impact on quality and productivity is also important. It makes it easier to identify problems and provide the best solution.

Establish documentation and maintenance 
Keeping an accurate, detailed log of all activities in a robotic welding cell can help welding supervisors maintain control over changes that could impact performance of the robotic welding system. Information to document includes:

• The names of all employees who enter the weld cell, when they entered and why
• Parts that have been cleaned
• Consumable changes
• Drive roll tension adjustments
• Installation of a new welding wire drum

This documentation provides insight into changes in the robotic weld cell, making it easier for maintenance staff to troubleshoot any issues. It can also help the welding supervisor and maintenance personnel determine the appropriate frequency for a preventive maintenance schedule, which helps reduce unexpected downtime.

This article is the first in a two-part series focused on key information welding supervisors should know to help ensure robotic welding success. Read article two, How Robotic Welding Supervisors Can Improve the Operation.

Understanding Fixed Automatic Welding Guns

When it comes to automating the welding process, many companies opt for robotic welding systems due to the flexibility they provide and their ability to reach and weld multiple joints. These systems provide the advantages of speed and accuracy and can be reprogrammed to manage new projects.

But these robotic systems aren’t right for every application. In industries such as oil and gas, railcar, structural steel fabrication and shipbuilding, joint configurations are often less complex, consisting of a single part to be welded as opposed to full assemblies. In this case, fixed automation welding is generally preferred.

About fixed automation welding

Fixed automation welding, sometimes called hard automation welding, is commonly used for welding pipes, structural beams, tanks and vessels in a shop environment prior to them being moved to the jobsite where they will be placed into service. It can also be used for welding steel plates for the general fabrication industry or in the manufacturing of hot water heaters and propane tanks.

One common factor in these applications is the need for either longitudinal or circular (inside or outside diameter) welds that require repeatability as opposed to versatility. Other factors that make applications suitable for fixed automation welding include:

1. A high volume of similar parts with low variety
2. Large parts with very long welds or several similar welds
3. Large parts that would be difficult to weld manually

In some cases, fixed automation welding can help companies meet high production goals at relatively low cost. And it is easy for a single operator to oversee and load parts, making it desirable from a labor perspective — particularly given the shortage of skilled welders the industry is facing.

A fixed automation welding cell can be set up in two ways. The first option requires tooling that holds the part in place, while a fixed automatic gun moves along the weld joint by way of a mechanized seam welder or a track and carriage that holds the gun in place. This option would be viable for a long structural beam, for example.

In the second scenario, the welding gun may be fixed in a single place by tooling while the part, such as a pipe, rotates on a lathe or circumferential fixture during the welding process. In today’s marketplace, there is equipment that can rotate parts in a wide range of diameters and weights.

Tooling for fixed automation welding offers minimal flexibility and can be expensive to adjust for new parts. This is true particularly in comparison to a robotic welding system that can be reprogrammed to articulate and weld in different positions along the X, Y and Z axes.

When investing in the tooling for fixed automation welding, it’s important for companies to determine upfront what their long-term applications will be. Will they continue to weld parts that are straight or circular for the foreseeable future?

Avoiding pitfalls in the process

One very important part of the fixed automation welding system is the welding gun. It is not uncommon for companies to take a do-it-yourself (DIY) approach to this piece of equipment, fixturing a semi-automatic gun in place with various components to mimic the performance of a fixed automatic gun. Sometimes this is done out of convenience, due to the shop having an abundance of semi-automatic guns, or because of a perceived cost savings.

Unfortunately, a DIY gun assembly for this process can be time-consuming to set up and maintain, which adversely affects productivity. It also is not optimized for fixed automation welding. Quality may suffer due to off-seam welds or other inconsistencies, leading to rework that further reduces throughput and increases costs. Also, if replacement parts are needed there could be variations in the assembly since it is not set up for this process. Again, this can lead to quality issues.

Instead, it is important to invest in a fixed automatic gun that is designed for the process. These guns have consistent components that can be sourced from manufacturers so that the welds are repeatable. And the gun manufacturers can provide service and technical support.

Looking at the choices

Guns need to be specified or customized for the application according to the available space, taking into account the distance between the gun and the part and also how far away the wire feeder is. These factors impact neck length and bend or angle, as well as cable choices.

Necks are typically available in the marketplace in varying lengths, from approximately 4 to 12 inches, and with either a straight neck or 22-, 45- and 60-degree bends. Companies need to determine the reach required to meet the weld joint, as well as the necessary angle for completing a sound weld.

Cable lengths vary from as short as 3 feet to as long as 25 feet. Longer cables are ideal for reaching a wire feeder placed further away from the part, including on a boom. In other situations, a company may mount the feeder directly on the tooling or nearby, in which case a cableless gun is an option for air-cooled operations. These guns plug directly into the wire feeder via a power pin and do not require a cable. Amperage and duty cycle also need to be factored into the selection of a fixed automatic gun, and both depend on the thickness of the material being welded and the amount of arc-on time required.

Air-cooled fixed automatic guns are typically available from 300 to 500 amperage models, offering either 60% or 100% duty cycle. Duty cycle is defined by the amount of time within a 10-minute cycle the gun can weld without becoming overly heated.

The necks on these guns are particularly durable since they have fewer internal channels than a water-cooled gun and rely on the ambient air to cool them. They are also more resistant to bending, and replacement parts are less expensive.

For higher-amperage fixed automation welding applications that require longer periods of welding on thicker material, a water-cooled gun may be a better choice. These models are typically available in amperages ranging from 450 to 600 amps and offering 100% duty cycle.

Hybrid water-cooled guns are another option. These fixed automatic guns have a sturdy neck similar to an air-cooled model with water channels running external to it. These channels make the guns easier to maintain than water-cooled guns.

Additional considerations

Along with selecting the appropriate components for a fixed automatic gun, it’s also essential to choose high-quality consumables — nozzles, contact tips and gas diffusers. This helps minimize downtime for frequent changeovers and supports production goals. They can also reduce quality issues that could require rework later in the welding operation.

Consumables are available that can be used across different types of welding guns, including semi-automatic ones and fixed automatic guns. This compatibility can be beneficial to simplifying inventory and preventing errors when installing new consumables on either type of gun.