Definition
Large equipment that cannot be moved into the module, which must be bulked, usually shared resources; curtains are generated by monuments.
In detail
A Monument refers to large shared equipment that cannot be moved into a cell and must be run in batches, such as a large stamping press or heat-treat furnace. It breaks one-piece flow and is a break point in flow within Cellularization. To balance efficiency, inventory buffers, or "curtains," are usually needed before and after it; if the Monument itself is a batch process, the number of curtains must be doubled. Identifying Monuments helps with layout and material flow planning, and the outputs are a clear equipment list and buffer strategy.
Example in practice
When planning a new production line, it is found that a large injection molding machine cannot be moved into the cell due to size and cost, and it must serve multiple products by running in batches. Its cycle time (including the batch) needs to be calculated, and curtain buffers set before and after it following the curtain rules — because it is a batch process, the curtain quantity must be doubled — to ensure single-piece flow within the cell is not affected. Through proper planning, equipment capacity is utilized while maintaining overall flow efficiency.