Robotic Water-Cooled Welding Torches - Problems and Solutions

Robotic MIG welding requires a choice when it comes to which welding torch to use for your operation. Your facility will need to weigh the options for using a water-cooled or air-cooled welding torch based on research you have done regarding both. Each torch type has its benefits and downfalls that can alter productivity. Is your torch providing the amperage ratings and duty cycle you’re looking for while staying within your budget? These factors are essential to consider, along with understanding common problems you will run into with your new equipment.

When leaning toward a water-cooled torch, you are looking at incorporating more equipment to keep the torch running smoothly. Beyond the torch itself, you will need a water cooler, coolant, and all the necessary hoses and fittings. More equipment doesn’t always lead to more hassle. Water-cooled torches actually extend the life of your consumables, meaning less changes and money spent on new parts. Higher amperage welding, for longer periods of time, is the key to water-cooled torches. In my experience, water-cooled robotic torches running at 100% can get back to a cooled state in as little as 30 seconds or as long as 2 minutes depending on the amperage load. Water-cooled torch systems can achieve such a quick cooling state because of the external cooling system.

Let’s take a look at two common problems you will likely run into with your robotic water-cooled MIG gun.

When The Problem Is A Leak…

Much like a leaking roof, the location of the noticed water leak may not always be the start of your problem. Identifying the source will be your biggest task, as the leak could be anywhere from the cooler or water lines to the torch or neck.

If leaking originates in the cooler, a simple repair or replacement is needed. If the water lines are leaking, things will start to get more difficult. Water lines, which lead up to the torch itself, can become damaged due to an external factor or internal condition. Whichever it is, a replacement is necessary. Connecting coolant lines correctly is essential for flow direction, meaning the “cool” line leads to the torch. If the connected lines are reversed, it could cause dislodged debris or particulate to form inside of the system and be forced into the smaller passageways of the neck, causing poor flow and overheating.

If the leak originates in the torch cable, much like the water lines, you will need to determine cause. If the torch bundle moves excessively or whips during the normal weld cycle, this action may cause premature wear. A cable support may be considered to minimize excessive cable motion.

If the water line in the torch cable is melting, then the focus should be on the cooling system. Insufficient volume of cooling fluid could be a factor. Is sufficient fluid in the cooler reservoir? If there is adequate fluid volume, the cooler system as a whole may be insufficient to cool the welding application. Coolers with larger reservoir volume, or even a chiller, may need to be considered as an addition to your process. These considerations would be for extreme welding circumstances.

When The Problem Is Overheating…

Overheating of torch front end parts is another major water-cooled welding gun issue. This potential problem is not exclusive to water-cooled torches, but rather welding guns as a whole. Heat is a major part of determining whether or not your torch will be successful. If the front-end parts of the neck are showing evidence of being overheated, resulting in the life of your parts being shortened, there has to be an underlying reason. Further, overheating can lead to weld porosity and wire burn back. If the life of your consumable parts has suddenly changed, here’s what to start looking for…

• Double check welding parameters
• Are they within specification/duty cycle?

The cable rating should always be sufficient for the welding process, including duty cycle.

However, an oversized cable is not going to transfer current any better than a properly sized cable. It may also be possible to use a higher amp rated neck, larger mass contact tip, or different contact tip material to address the overheating concern.

Next, check all front-end parts (nozzle, tip, tip holder) to see that they are attached securely. Loose parts will lead to overheating and possible weld failure.

If parameters and parts do not reveal the source of overheating, the cooler or circulator should be examined. Is the fluid clean? As a part of normal maintenance, coolers should be back flushed periodically to remove any debris. Air flow through the cooling fins or cooler must be adequate. Further, dust accumulation can reduce cooling efficiency. Periodic maintenance is necessary to clean the radiator or cooling surfaces to prevent the insulating effect of dust accumulation.

Coolers should have a flow switch installed. A flow switch will prevent the torch from working, if insufficient flow or pressure isn't reaching the torch. Inadequate coolant flow or pressure would lead to the torch overheating, resulting in reduced consumable life.

In Conclusion

Robotic water-cooled welding torches have a number of operational benefits to consider when deciding if this torch type is right for you. The question is, do those benefits outweigh the downsides? As you determine some of the major pain points, you can help understand your equipment to get the most out of the torch, resulting in higher productivity.

No equipment is going to be perfect. There is always something that goes wrong, but being prepared and knowing how to handle the issue is what can set your operation apart from others.

Interested in learning more information about robotic welding torches? Check out our Definitive Guide to Robotic Welding Torches by clicking the button below.