Viking Plastics of Corry, PA, is a global supplier of engineered, injection-molded and assembled sealing components to many industries. Its products include plastic connectors, closures, clips, brackets, caps and fasteners.

Recently, the company implemented a system that automatically installs rubber seals, called Quad Rings, into plastic caps. The system also detects short-shot caps and verifies the presence of a Quad Ring in a cap. Increased throughput and elimination of visual inspections have considerably improved quality and productivity.

The eight-station system, which was built by Automated Industrial Systems Inc. in Erie, PA, employs a cam-driven rotary indexing table with double-nest fixtures at each station. A stainless steel vibratory feeder bowl with a bulk hopper supplies two feed lines for the caps. At the first processing station, a pick-and-place device transfers two caps to a fixture on the dial.

At the second station, a dual-head lubricating system sprays the inside of the caps with a lubricating mist to facilitate seating of the Quad Rings. Stations 3 and 4 are each equipped with an internal seal installation machine and a stainless steel feeder bowl and gravity track to feed the rings to a nest. There, they are removed by a transfer mandrel, rotated 90 degrees downward, and placed into the caps. Each machine places one ring into one cap.

Station 5 verifies that a Quad Ring has been properly placed in each cap. It also identifies different cap styles to be sorted at the unload stations for good assemblies. At Stations 6 and 7, good cap assemblies are removed and placed into bulk containers. After one container is filled to a predetermined level, the cap assemblies are diverted into a new container. A signal alerts the operator to remove the full container and replace it with an empty one. Station 8 is used as a reject station for bad product. All parts and debris removed here are delivered to a remote location to prevent the possibility of getting mixed with good parts.

The entire system is mounted on a fabricated steel frame. It is controlled by an Allen-Bradley MicroLogix 1500 PLC with a PanelView Plus 600 operator interface touch screen control panel, which displays machine status information. Among other information, the panel shows how many good assemblies have been placed in each container at stations 6 and 7. It also keeps track of the total production per shift. All eight stations are constantly monitored, and critical performance information is displayed to the operator.

For more information on plastic assemblies, call Viking Plastics at 814-664-8671 or visit

For more information on programmable controllers and operator interfaces, call Rockwell Automation at 440-646-3434 or visit

For more information on O-ring and seal installation, call Automated Industrial Systems at 814-838-2270 or visit


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