Manufacturer increases robotic welding cell productivity with machine vision retrofit

Situation

Schenck Process, a provider of applied measuring and process technology, was having trouble with a robotic welding cell at its Sabetha, Kan., production facility. The main problem was programming. It was time-consuming and tedious, so the company used the cell for only a limited number of parts.

The cell was programmed with a teach pendant. During programming, the operator had to be in the cell, following every robot movement, which meant the cell had to stay idle until programming was completed.

The process for one complex part could take 90 to 120 minutes. For parts like a relief valve with a pipe-in-pipe design, programming for the robotic cell was too complicated, so the valve was welded manually instead.

Resolution

Abagy retrofitted a robotic cell for Schenck Process, installing machine vision and other hardware that is compatible with proprietary software. Setup time for a new product has been reduced to 10 to 15 minutes (a rotor with 18 welds takes about 10 minutes), and the robot can be used for far more products than before—a benefit with Schenck’s high-mix production.

While the robotic cell is used mainly to weld rotors, other product types can be added if necessary. During the first month of the cell’s operation after the retrofit, 50 different technical charts were created. Now, with nearly 100% automatic programming and operation, the relief valve is being produced with robotic welding.

The cell has two working zones. Before the retrofit, it required a separate program for each zone, but now one technical chart created for the product will work for both areas.

Previously, Schenck Process had to measure everything with a ruler when installing each part, as even a small deviation would lead to rework. Now the retrofitted cell tolerates deviations.

Programming now is performed at a desk rather than in the cell, making the process less strenuous for the operator and less prone to error. In addition, the robot can continue to work on a project while the operator sets new tasks for the cell.