Understanding Torch Mounts
There are two types of mounting options available for welding jobs: over-arm and through-arm mounts.
The more common set-up today for robots today is the through-arm solid mount. This provides for a much "cleaner" end of the torch and provides for clearance in tight areas when reaching down inside of fixtures. Brackets and fittings are also eliminated, providing for a reduction in overall hardware. Programming headaches are less frequent as through-arm technology has proved to be more modern.
Through-arm torches can use collision mounts or solid mounts.
Collision mounts enable early and quick detection of a collision and will shut the torch off if the swanneck contacts any fixtures, persons, or other materials. This provides a reduction in damage if an accident would occur.
You could also choose a solid mount and install collision software that will offer the same processes through an external controller. When the controller senses a brief rise of motor amperage outside of the expected range, the robot will then pre-emptively shut down as a protective measure.
The final evaluation of a solid mount includes understanding how strong and repeatable it is by looking at the dowel pins, the dowel pin size versus position, the material of the sold mount, and the material thickness of the flange going onto the robot.
Over-arm torches were the pioneers of robotic welding.
This set-up can put the torch at obscure angles in tight places that could not be accomplished with a through-arm. However, the process requires a bit of modification and time.
Over-arm mounts do provide easy maintenance as the entire torch package is outside of the arm and parts can be maintained and fixed quicker than through-arm. Furthermore, over-arm mounts use a series of dowels and form the basis of a shock sensor which can take a direct impact in the Z direction.
They use a solid mount or collision mount. Just like through-arm, it is important to make sure the robot has on-board collision sensing.
Then, it is important to look at and understand the mount patterns, torch angle, and clearance. A good mount will be the strong point in the event of a crash as it is less time-consuming to replace a damaged torch neck than torch mount.
If you choose a breakaway style for a torch mount, the effectiveness relies on proper installation. It is important to choose the correct adapter plates and proper spring pressure for the torch/equipment weight.
Torch Mount Best Practices
It is important to really study and understand the repeatability, ease of installation, and how the mount arm clamps to the collision sensor with your robotic system.
Evaluating the mounting accuracy will provide a better and more consistent product. Reliable robot welding torch mounts will have consistent repeatability to minimize any necessary reworking and ultimately keeps the productivity high.
Regardless, the set-up of both styles should evaluate solid machine surfaces and a minimum number of bolt up components as this will lead to a more solid and repeatable mounting structure.
For more information on torch mounts, contact the representatives at RobotWorx online or at 740-251-4312.