• Click Objects and Containment and create an object called Part1. Uncheck the default image and select an image for Part1. (Brown Dot).
• Create a start process that creates objects of type part1. Add 2 generic processes, “Load Conveyor” and “Unload Conveyor.” Add the End process.
• Connect the flow, Start to load conveyor, load conveyor to unload conveyor, unload conveyor to end.
• Right click on the connection line between load and unload conveyors, and select insert connector. Resize the connector using the connector handles.
• Right click on the connector and select copy. Paste 3 copies of the connector on the canvas and connect them using connection lines.
• Select (using the control key) all connections leading to the unload conveyor except for the last one, right click on any one and open the item properties. Edit the “Behavior: Conveyors, Polling and Carriers.” Check the box for “Belt Conveyor Behavior.” Change the “Connection speed, distance and capacity” settings, and “enable auto-distance calculation based on grid setting.” Make sure to check the “Apply time properties/capacity/cost to all selected connections.”
• Select the last connection, name it “Accumulating conveyor” and modify its “Connection speed, distance and capacity.” Uncheck “Fixed Trasnfer Time”. Change the time units to Time Units and click “Enable Auto-Distance calculation based on grid setting.” Change the line capacity to 15.
• Open the Process/ Object/ Condition Routing for Load Conveyor. Change the Next Process for Default Routing to Unload Conveyor.
• Run the simulation, and examine the behavior on each one of the conveyor segments.

Link to Defining Accumulating Conveyors (PDF)