Scheduling Operation Activities

In order-based scheduling, the production order is at the core of the planning process. Scheduling occurs at the operation level within each order, considering critical factors such as dates, priorities, sequencing, and resource constraints. This approach is distinct from SFC-based scheduling, which focuses on individual Shop Floor Controls. Order-based scheduling ensures the coordinated execution of operations as part of an integrated order-driven strategy. This chapter covers the principles, options, and advanced features of order-based scheduling in SAP Digital Manufacturing, while SFC-based scheduling will be discussed in the next chapter.

Order-based scheduling in SAP Digital Manufacturing offers a wide range of options to plan and control production orders flexibly and efficiently. These settings help you model both serial and parallel flows, as well as manage workloads and queues.

• Scheduling Modes
  • Infinite: Allows scheduling operations even if multiple overlap on the same resource, permitting intentional overloading.
  • Find Slot (Finite): Schedules an operation into the next available slot with available capacity.
  • Insert: Places an operation between existing ones, shifting others accordingly (unless they are fixed in place).
• Scheduling Directions
  • Forward: Schedules from a chosen starting point into the future.
  • Current: Starts scheduling from the current system time—useful for immediate reallocations after disruptions.
  • Backward/Midpoint: Uses the end date as a reference; predecessors scheduled backward, successors forward.
• Shift Breaks
  • Included: Ensures operations do not run during shift breaks; adjusts operation end times.
  • Excluded: Ignores shift breaks in scheduling.
• Primary Resources: Limit scheduling to specific (preferred) resources or consider all eligible alternatives.

Order-based scheduling combines automated efficiency with manual flexibility to ensure timely and resource-effective execution of orders.

• Automatic Dispatching (Auto-Dispatch): Automatic dispatching uses system-driven algorithms to assign and sequence operations, minimizing manual intervention while optimizing schedules.
  • Heuristic-Based: Primarily works in a forward direction; operates in Infinite or Find Slot mode.
  • Order Prioritization: Schedules released and high-priority orders first; sorts ties by release date.
  • Resource Assignment: Tries the default resource first (as defined in master data), then considers alternates.
  • Load Balancing: Distributes operations across all eligible resources using logic based on resource type or material.
  • Backlog vs. Active: Separates past-due/unprocessed (backlog) from planned/ready (active) orders.
  • Benefits:
    • Highly automated and consistent scheduling.
    • Uniform priority handling.
    • Full transparency through tools like "Last Scheduling Results."

• Manual Dispatching: Manual dispatching enables planners to directly intervene, especially for outliers or exceptions where automation may fall short.
  • Use drag-and-drop in the Gantt chart to assign or reassign operations.
  • Manage urgent/rush orders or reallocation after auto-dispatch.
  • Benefits:
    • Maximum flexibility for responding to changes or disruptions.
    • Faster reactions to last-minute or high-priority needs.

To further optimize production planning, SAP Digital Manufacturing offers advanced features:

• Purpose: Divide an operation’s unconfirmed quantity into multiple sub-operations.
• Benefits: Enables parallel processing on different resources. This is useful for:
  • Balancing material shortages.
  • Overcoming capacity bottlenecks.
  • Continuing work after disruptions.
• Limitations: Only works with forward scheduling in Infinite or Find Slot mode.

• Purpose: Combine split sub-operations back into a single operation (if not yet started).
• Benefit: Restores unified process flow after exceptions.

• Purpose: Allow successor operations to start before predecessors finish, reducing overall lead time.
• How: Configured in the originating order (for example, SAP S/4HANA); effective on initial order download.

Order-based scheduling also provides direct controls for planners.

• Deallocate: Remove operation from a resource and return it to the worklist (not for "Fixed" or "Overloaded" operations).
• Fix/Unfix: Lock or unlock an operation for rescheduling or deallocation.
• Order View: Visualize the entire chain of operations within an order, including predecessors/successors and any overlaps.
• Load Balancing: Adjust how auto-dispatch distributes work across resources.
• Review Results: Access and export the last scheduling outcomes for analysis.

Order-based scheduling in SAP Digital Manufacturing empowers you to handle simple and complex production scenarios with maximum transparency and control. By combining manual and automatic scheduling—and leveraging advanced features like operation split/merge and overlapping—you can ensure on-time delivery, efficient use of resources, and robust production performance under any conditions.

1. To create individual SFC schedules from released orders.
2. Open the Dispatching and Monitoring app and choose SFC Schedule View.
3. Enter the order numbers (separated by spaces, commas, or line breaks) and choose Go to load the Released Orders Worklist.
4. Select the desired orders using the checkboxes and choose Generate SFC Schedules.
5. Optionally, chooseSFC Schedules to review the generated schedules and their details.

After generating SFC schedules, switch to SFC scheduling mode:

1. In the Order Worklist, access Filters and set 'Enable Scheduling to Cluster Operations Based on Routing' according to your requirements:
   • YES: SFC operations are dispatched to resources based on resource type mappings defined in the routing.
   • NO: All SFC operations are dispatched to the primary resource regardless of resource types. This is used when you want simplified scheduling where all operations go to one main resource regardless of routing configuration.
   • Example: Your routing defines that milling operations should go to Work Center A and drilling operations to Work Center B. With "YES", the system respects this and schedules accordingly. With "NO", both operations go to whichever work center the algorithm determines as primary.
2. Choose Switch to SFC Worklist to enter Scheduling Mode: SFC.
3. The Gantt chart will display "Scheduling Mode: SFC" and show SFCs with a light green border for visual differentiation.
4. Schedule SFCs using the same methods available for operations:
   • Manual: Drag and drop SFCs to desired work centers.
   • Automatic: Apply scheduling algorithms for optimal resource assignment.
5. Save the schedule.

• Coexistence: SFC-based schedules can share work centers with order-based schedules in the same Gantt chart view.
• Reverting Schedules: SFC schedules can be deleted at any time by clicking 'Delete SFC Schedules'. This restores the operation-level scheduling, and SFCs will reappear in the Order Worklist.
• Execution Synchronization: The Work Center POD is tightly integrated with Resource Orchestration. When configured accordingly, scheduled SFCs will only appear and can only be executed at their planned resource.

SFC-based Scheduling introduces MVP support for Process Orders within Resource Orchestration:

• Partial Order Release: Process orders received from ERP can be partially released, creating individual SFCs (Charges) for specific batches with varying quantities.
• Independent Charge Scheduling: Each charge can be scheduled independently to different resources based on capacity, load, and other constraints.

In order-based scheduling, all quantities of an operation are treated as a single batch and scheduled together at the operation level. While this approach works well for coordinated, order-driven production, it lacks granularity when individual units need different paths or timing. SFC-based scheduling overcomes these limitations by providing:

• Unit-Level Granularity: Schedule and dispatch individual production units or charges independently, rather than treating entire operation quantities as one batch—enabling true unit-by-unit control.
• Dynamic Routing Flexibility: Each SFC can follow its own optimized path through the factory based on real-time conditions (capacity, material availability, priorities), rather than following a fixed operation sequence for the entire batch.
• Targeted Resource Assignment: Assign specific SFCs to optimal resources independently, avoiding the constraint of scheduling entire operation quantities to the same resource—ideal for make-to-order, high-mix production, and process industry scenarios with varying batch sizes.