Understanding Repetitive Manufacturing Setup
Repetitive or rate-based manufacturing of discrete products uses manufacturing techniques that are associated with achieving just-in-time or flow line production. Repetitive manufacturing aims to achieve the continuous production of a mix of similar items on a specialized flow line rather than the traditional work order with its fixed quantity and due date of a single item. It is usually the preferred method with families of products that have minor variations among products with a constant, high-volume demand, such as cameras and electronics.
Repetitive manufacturing dedicates entire production lines to a family of products. These product families share similar components and routing instructions. Generally, these products are manufactured in a continuous process, which requires less inventory movement to and from the production line. Work center setup and changeover times among related products are minimized.
Equipment and work centers are designed to manufacture a family of products and enable quick setup changes. Repetitive environments define production in terms of units per hour. The capacity for the line is determined by one constraining operation. You define the constraining operation as the slowest cell in the line. Scheduling this line requires the tools to schedule, sequence, and balance production. Balancing the line so that the workload is distributed evenly along the production line is very important and you can produce a mix of products with different constraining operations. This product mix, when properly sequenced, enables the production line to operate consistently and efficiently.
The product mix is typically not a large batch of one item. Instead, the mix is the integration of different variances within the product family members through the production line in an order that optimizes the production line. For example, when manufacturing cameras, the cast body remains the same while certain components vary, such as top and bottom covers. The production line can be mixed by ordering the production of cameras: 3 black, 2 silver, 1 black with silver trim, 3 black, 2 silver, 1 black with silver trim, and so on. This product mix meets production demand.
To supply the product line, inventory can be pulled from stock or another work center and delivered as needed to the consuming operation or delivered directly to the line by external suppliers. While requirements for material are driven by demand, movement is controlled by visual cues called kanbans. The kanban authorization to produce is generated by actual demand.
Repetitive manufacturing:
Decreases work-in-process inventory.
Increases responsiveness to the customer's requirements.
Reduces leadtime.
Ties inventory consumption to production completion.
Ties frequent supplier deliveries to actual production demand.
Minimizes non-value-added activities.
Note: All items that are produced in a repetitive manufacturing environment must have an Order Policy Code value of 5, defined in the Item Master program (P4101) or Item Branch program (P41026). This value defines the item as a rate scheduled item.