When you think of welding automation, cable assemblies are probably not the highest priority when evaluating options. But you may be overlooking a critical part of the torch as you go through all the different robot torch options out there. Without question, the quality of your cable assembly plays a key role in maximizing the efficiency of your automated welding processes.
Think of what the torch's cable assembly does for the torch itself: the cable assembly provides all the power from your wire feeder, to your contact tip, all the way to your filler metal. When utilizing automated welding processes, it is ideal to have a very limited amount of downtime between welds. To do this you're going to need a very good cable assembly. A better cable assembly allows for more production, creates a higher quality product, and increases the profitability out of your welding cell.
To find a good quality cable assembly you're going to need to know what separates a good robot welding cable from a not so good one. There are very clear physical and spec characteristics in a robot cable that are telling signs on the cables' quality and it's fit for your welding automation. First, it's important to make sure you are using the proper cable assembly for your needs. This speaks to the cable rating.
The cable rating should always match up with the welding process that you need to perform. You also need to know what current is going to be running through your cable, how long the duty cycle is. An oversized cable is not going to transfer current any better than a properly sized cable. It is a waste of money and resources to use a cable rated higher than your needs. If you only need 300 amp to get a quality weld output out of your materials, a 600 amp cable isn't going to weld any faster or any better. If your machine is only designed to provide an amperage output of 350 amp, a 600 amp cable is only going to weld at 350 amp.
Physically speaking, a good quality cable assembly is going to have good quality wear protection. Things such as insulation and cable covers that are rigid enough to protect the cable from the elements, but not too rigid that it restricts the cable's flexibility.
A worn cable will have decreased current transfer, increased resistance, and hot spots in different sections of the cable, which is an obvious safety hazard and can put your robot down, which can have a really adverse effect on production.
When looking at options for cable assemblies, check over the entire cable to inspect the build quality. Things to look out for are :
For over-arm cable assemblies, another thing to consider is proper cable length to fully extend your robot arm and reach certain welds. A cable assembly that is slacked and pulled frequently will wear much faster.
A poorly made, or bad quality cable will break much quicker under the additional stress. Some cables may even have wire feeding problems from the cable being bent and twisted repeatedly.
Finding the right balance of slack that doesn't limit the arm's capabilities, but also doesn't put too much wear on the cable is imperative to getting the most out of your cable assembly.
Through-arm assemblies still require a cable and this cable performs the same functions as an over-arm system. The biggest difference and most important part of a through-arm system is cable length, this is critical as there is little room to go beyond the specification for the cable length.
Most specifications for through-arm cable length are plus or minus a few millimeters. This is far different from an over-arm system, as plus or minus six inches or even a foot will be okay.
Another option for robot welding cables are the water-cooled cable assemblies. Water-cooled cables are great because they dissipate the heat created during current transfer. A 500A, air-cooled cable is nearly 3/4" in diameter, while a 500A, water-cooled cable is about 3/8". In a water-cooled assembly, the neck is water-cooled as well. This means that the water will go down to the tip holder to help dissipate current transfer heat and reflective heat from the contact tip. If a water-cooled assembly is out of your price range, than you might want to look into hybrid cable assemblies.
In a hybrid cable assembly, the cable itself is air-cooled, while your front end parts (neck, contact tip holder, etc.) are water-cooled. That means you still get all of the advantages of a water-cooled front end with the cost savings of an air-cooled cable.
Using a hybrid cable assembly might not be best for your specific welding process because there is a possibility for amperage limits, as well as increased wear and tear from using the less durable air-cooled cable.
When choosing a cable assembly for your welding automation processes, be sure to take into account all of the available options and choose the right assembly for your needs and budget, but make sure that you never overlook the importance of a good quality robot welding cable as putting in the extra time and money upfront will pay major dividends when it comes to production up-time.