The Importance of Understanding your Swannecks
Swannecks are an important element to pay attention to in order to provide optimal repeatability and consistent product quality to your production line.To better understand the durability of a robotic torch and swanneck it is important to understand the weak and wear points, construction, tip holders and diffusers, materials, and wire liners.
Keying of the Swanneck
Two keyways located on the front module of the robot torch has ramifications to the torch neck’s repeatability.
For instance, if the soft keyway is on the front module of the robot torch then the integrity of the front module erodes the swannecks durability, and the swanneck will begin to lose its tool center point.
The hard keyways cause rotational movement and wear in the neck and should ideally be built into the torch module.
Picture Credit: The Definitive Guide to Robotic Welding Torches by Abicor Binzel
It is also important to understand the construction of the swanneck when choosing a robot torch. A single piece of construction of the swanneck is going to be sturdier than swannecks manufactured from multiple components.
In order to have higher up-time, throughput, and ROI, it is important that when you remove a swanneck and replace it, you want to maintain a true tool center point (TCP) and not have to continuously touch up your robot to account for TCP variance.
Tip Holders and Diffusers
Tip holders are the interface between the swanneck and the contact tip and are an important piece to understand. Torch makers have different ways to construct tip holders and diffusers.
Some use a single piece construction by combining the diffuser and the tip holder into a single component. This offers better conductivity in the piece and greater shielding gas coverage than with two threaded pieces. Some propose that because it is a single piece construction of a long, copper material there is an increase for bending at the piece, causing misalignment of the contact tip, wire, and joint. However, a shorter contact tip holder won’t experience these problems because the bend-ability is almost nonexistent.
They also can make them into separate pieces and manufacture the gas diffuser as a single piece conductor tube.
The diffuser will perform better in crashes and help maintain the Tool Center Point if there is a collision when it sits inside the swanneck end and is supported against the outer tube of the swanneck. If there are a larger number of big bores then the distribution and resistance to spatter will be higher.
Diffusers and tip holders typically utilize brass or copper as their main build material.
- Copper is a softer metal; it wears quickly but it will achieve good conductivity into the contact tip.
- Brass will resist wearing as it is a harder metal but there will be some sacrifice in conductivity.
Even understanding the type of tip used in relation to the diffuser is important. A contact tip made from silver plate or pure electrolyte copper will provide the most from a brass diffuser; however, a contact tip made from copper zirconium would be best used with a copper diffuser as the current will provide a better transfer to the tip.
A typical wire liner will start from the wire feeder and go all the way up to the contact tip. There are two different popular liners that are used: neck liners and front load liners.
- Neck liners (also known as jump) are easy to use liners that save time and material cost in the replacement and maintenance of liners. These liners start at the torch body and travel all the way to the contact tip. Jump liners are cost saving materials to have on hand because they protect against a liners’ weakest point which is on the torch body itself. Jump liners can be quickly switched enabling production to continue.
- Front load liners use mechanical springs that don’t always perform properly. They are easy to install so they do provide convenience and time savings, but it is important to make sure they are the right length and correctly installed on the spring.
Liner material is another important choice to make. These can be helical versus a flat design and steel or metallic versus plastic in material. Flat liners are not as flexible.
It is extremely important to choose the right diameter as well; an oversized liner can have too much area around your wire and cause bird nesting and mis-feeding. Ensure that the liner size is matched to the wire size for optimal results.
As you can see, there is an abundance of information available on swannecks, diffusers, and tip holders. For any questions or for more information contact the experts at RobotWorx online or at 740-251-4312.