Project Details
Foundries are typically automated with OEM equipment on the molding side but are often labor-intensive in the after-mold processes. These activities present challenging safety, environmental, and ergonomic issues.
Technology developed by MESH for post-mold grinding of the parting lines and prefacing can help solve these problems.
In this case study, the customer required a system that could relieve their operators from the manual tasks of grinding parting lines and prefacing their pipe fittings. The customer chose a semi-automated process where the loading of the pipe fittings was done by the operator with the assistance of a hoist, but the grinding, facing, and offloading were performed by a foundry-duty robot, appropriate fixtures, regrip stations, and end-of-arm tooling.
After a thorough process review with the customer and a solid understanding of the finished goods requirements, MESH designed and built two systems that accomplished these tasks.
Fixture Design
Fixture design was an important part of the system due to the large number of parts the customer processed and the short part runs. Pipe fittings ranging from 4” through 16” of various types (90-degree elbows, 45-degree elbows, tees, straight couplings, reducers) had to be accommodated.
- The fixture shown in the gallery had automatic and verifiable clamping, with quick-change size discs being swapped out as needed.
- The quick-change size discs were made from hardened 4140 for extra durability.
- Two fixtures were mounted on a 360-degree servo positioner (controlled by the robot), with one side exposed to the robot and the other in a safe zone for the operator to load raw parts.
- After grinding, the robot placed the part on an outfeed conveyor (not shown).
Grinding and Gripping
Part gripping was one of the most challenging technical aspects. To address these challenges, MESH used a servo-actuated gripper with torque monitoring and special jaws that combined soft compensation and hardened jaw pads. Some pads were swapped out depending on the product.
The MESH-designed grinding station used a diamond wheel for material removal mounted on an industrial grinder with horizontal compensation. This compensation regulated the pressure regardless of the robot’s position on the part.
Robot Selection
Due to the harsh environment and the requirements for reach, load inertia, and tooling weight, MESH chose an ABB IRB6700 foundry-duty robot with SafeMove.
Part Positioning
Typical of robotic machine tending applications, a regrip station was needed for some parts (like tees). The pictures in the gallery show the MESH-designed regrip station.
