1. 4/27/2004Extending SP95 for Batch Scheduling Extending ISA SP95 for Batch Scheduling by Steve Morrison, Ph.D. Chem. E. Info@MethodicalMiracles.com

2. 4/27/2004Extending SP95 for Batch Scheduling SP95 in light of the S88 Standard SP95 Product Definition SP95 Production Capability SP95 Production Information Additional Classes for SP95 Role of Materials, Connections and Campaigns History vs. Schedule Objects Extending SP95 Objects for Batch Scheduling

3. 4/27/2004Extending SP95 for Batch Scheduling 1. What’s a Unit? a)A process area: a collection of equipment b)A collection of operations that must run on the same equipment A Test of S88 2. Which recipe makes the actual batches? general b) master c) control 3. What is the lowest granularity of execution a) unit b) operation c) phase d) other 4. What acquires and releases resources?

4. 4/27/2004Extending SP95 for Batch Scheduling S88 Was a great step forward for common batch definitions, but… Overkill for many plants and mills. Do batch plants all need General Recipes and Site Recipes for Control Recipes? Even control recipes were not made for continuous aspects. SOC’s SOP’s, and Product Production Rules are better for many of those. Since We Have S88, Why SP95?

5. 4/27/2004Extending SP95 for Batch Scheduling How many batch plants do not have a single piece of equipment that is continuous? S88 did not specify many things: materials, lots, process segments, tests, equipment classes, work cells, personnel, history, etc. More S88 Shortcomings

6. 4/27/2004Extending SP95 for Batch Scheduling Batch – S88 or other recipes  General – Chemist’s recipe  Master – quantities, resource candidates  Control – all choices and durations. Can be reused, so not exact times Continuous – SOP or SOC SP95 introduces Product Production Rules as an option SP95 Product Definition

7. 4/27/2004Extending SP95 for Batch Scheduling G,M,C Recipe G,M,C Unit G,M,C Operation G,M,C Phase Equipment (unit level) Equipment (non-unit level) Material Personnel Pipes, Manifolds, Connectors SP88 Classes

8. 4/27/2004Extending SP95 for Batch Scheduling Product Production Rule Product Segment Product Segment Execution Order Process Segment Material Sublot Equipment Personnel Pipes, Manifolds, Connectors ( temporary or permanent ) ( all types ) Product Production Rules

9. 4/27/2004Extending SP95 for Batch Scheduling The Enterprise has Sites, containing Areas, which contain Equipment and other items Continuous Production Units, batch Process Cells, and repetitive Production Lines Equipment – dedicated (unit) and non- dedicated (non-Unit) distinction is lost No intermediate objects (non-dedicated pumps, centrifuges, washers, filters, manifold rooms) SP95 has equipment maintenance objects too SP95 Production Capability

10. 4/27/2004Extending SP95 for Batch Scheduling Material – batch centric, not schedule centric. Is an intermediate product a material consumed or a material produced? (pick only one!) - causes problems with global planning Material definition vs. material lot vs. (recursive) material sublots SP95 Materials

11. 4/27/2004Extending SP95 for Batch Scheduling Personnel – positions, not individuals Process segment – Temporary or permanent grouping of equipment, materials, and personnel Other SP95 Production Capabilities

12. 4/27/2004Extending SP95 for Batch Scheduling What is Needed to Schedule Production Requests (in a Schedule) Production Rules (Recipes) Production Capabilities (Site resources) Production Responses (History) Past Current Future Maintenance? actuals requirements specifications -

13. 4/27/2004Extending SP95 for Batch Scheduling Enhancements to SP95 Materials – MRP II typically materials only. Equipment often more important than material in a plant. Need equipment and materials together. Inventory vs. rate, spikes Connections – Requirements and Capabilities – homogeneous vs. heterogeneous

14. 4/27/2004Extending SP95 for Batch Scheduling Production Request Enhancements Campaigns – Campaign lead time, end buffer, setup, startup, and cleanup times. Prior steps, yield and stoichiometry, feed inventory, global planning impact, multiple successor campaigns, and batches within campaigns. Orders for grouping campaigns. i.e. Production Requests need multiple levels of dependencies on other production requests

15. 4/27/2004Extending SP95 for Batch Scheduling

16. 4/27/2004Extending SP95 for Batch Scheduling 1. Instead of tasks, why not just use the SP95 requirement objects? You can, if you make additions and change the intent of some of the classes. 2. Why not just use history objects for scheduling? These could be the same, except that the attributes, states, methods, and lifecycle are different. SP95 was right to separate them. Questions on Proposed Enhancements

17. 4/27/2004Extending SP95 for Batch Scheduling SP95 Production Schedule Objects SP95 has a family of requirement objects for equipment, material produced, material consumed, consumable expected, and personnel, which are all children of the segment requirement Interestingly, only the segment requirement has timing information. Furthermore, the only timing information it has is Earliest Start Time, Latest End Time, and Duration

18. 4/27/2004Extending SP95 for Batch Scheduling Problems Using Segment Requirements 1.The timing information only being in the segment requirements is probably fine for process segments (in recipes) and segment responses (in history), but is not sufficient for a robust schedule. 2. The only timing information is Earliest start time and Latest end time. Also required is Planned start and end time, and (depending on the architecture) Actual start and end time.

19. 4/27/2004Extending SP95 for Batch Scheduling Problem with Time Only in the Segment Does the segment start if one resource it requires is not yet available? Are the other resources free for others to use while waiting for the latest segment? It might be time for the segment to run, except that it is in a waiting for resource state. Different resources might be assigned to the segment at different times, even though everything in the segment only runs at the same time.

20. 4/27/2004Extending SP95 for Batch Scheduling Enhancing Requirements (Tasks) resource ClassResource specification ResourceSegment Requirement DescriptionUID (primary key) QuantityPredicted StartTime Quantity Unit of MeasurePredicted Duration … the following for materialsPlanned StartTime Material LotPlanned Duration Material SublotConstraints absolute/relative Start, Delay Location

21. 4/27/2004Extending SP95 for Batch Scheduling The Shortcoming of Data Historians They all run out of data!

22. 4/27/2004Extending SP95 for Batch Scheduling History objects show what has happened, and what is happening (in cases like batches that have started but not ended yet.) Schedule objects show what is happening, what will happen. Some future events are too near the present to change. Other future events are changeable and need to be scheduled in detail. Farther in the future events need to be seen and scheduled, but CANNOT be optimally scheduled in detail History vs. Schedule Objects

23. 4/27/2004Extending SP95 for Batch Scheduling Schedule changeable horizon, short-term scheduling horizon, vs. long term scheduling horizon Planned vs. Actual: Comparison of the values, as well as what is anchored. Heavy-weight schedule objects vs. lightweight history objects What-if scheduling: Multiple similar copies of the same future batch information. Archival: Only past history need for last five years or more. Why Not Combine History & Schedule?

24. 4/27/2004Extending SP95 for Batch Scheduling (Control) Product ProductionRuleProduct Production Rule NonOptimal DeltaTime StartTime (can be blank)Start Time End Time (can be blank)Source for Start Time Planned DurationEnd Time (can be blank) ArtificialCostForTheBatchSource for End Time BatchStartDelay (implicit) DelayComments (implicit) IsFeasible Batch Example : Schedule vs. History

25. 4/27/2004Extending SP95 for Batch Scheduling (Actual or hypothetical) [Control] ProcessSegment (Actual) SegmentResponse NonOptimal DeltaTimeStartTime StartTime (can be blank)Source for StartTime EndTime (can be blank) PlannedDurationSource for End Time ActDuration = End – Start Anchor -duration, start, end(implicit) Corrector (implicit) Anchor comments ArtificialCostPerMinute ArtificialCostToUse AvailableSlackTime (implicit) IsFeasible Equipment Schedule vs. History

26. 4/27/2004Extending SP95 for Batch Scheduling Planned vs. Actual: Multiple plans Long term What-if: order changes, re- prioritizing campaigns, fulfilling production at different sites, and buying new equipment. Short term What-if: Simulate the best options when a batch is delayed or equipment breaks down. This helps to quickly view alternatives and minimize scheduling mistakes. Scheduling Distinctives

27. 4/27/2004Extending SP95 for Batch Scheduling Cross-Batch Comparisons: For the same material, why do some batches take longer than others? Plant Comparisons: Even with somewhat similar equipment, why are some plants better than others at making the same product? More Scheduling Distinctives

28. 4/27/2004Extending SP95 for Batch Scheduling SP95 is a good starting point for scheduling, because scheduling was considered in the standard. However, a number of scheduling objects need to be added, because SP95 history objects are no replacement for scheduling objects. For many types of scheduling SP95 also needs to be enhanced in the areas of Materials, Connections and Campaigns Summary of SP95 Enhancements

29. 4/27/2004Extending SP95 for Batch Scheduling If you have questions later, feel free to contact me at: Info@MethodicalMiracles.com Questions?