Setup Matrixes

Several PP/DS master data updates improve setup matrixes, which contain the setup duration (how long it takes to set up a resource, such as a machine) and setup costs involved in changing a single resource from one setup status to another. One update relates to transition times between different products or groups of products. In manufacturing, transitions from A to B or changes from A to C, B to C, or B to A could result in different transition times. Cleaning duration and machine preparation also could affect transition times. The updated setup matrixes provide more accurate scheduling because you can consider dynamic transition times between two consecutive products.

In addition, SAP SCM 5.0 includes a new generation of complex setup matrixes that combine simpler matrixes and characteristics. With this process, you maintain two simple matrixes and then combine them when you want a more complex matrix. For example, using formulas, you could join a matrix for colors with a matrix for sizes to generate a more complex matrix. This way you avoid having to spend a lot of time maintaining the complex matrix because you only have to maintain the simple matrixes that make up the complex matrix.

If you integrate SAP APO with mySAP ERP 2005, you can integrate setup groups (characteristics of a given operation) and setup keys (details about the setup status for a setup group), which was not possible before. This reduces maintenance efforts and decreases errors because you maintain data only in one system.

Also with SAP SCM 5.0, you can now decide how resource usage influences setup duration. Until now, the system did not take resource usage into account when it calculated setup duration. For example, say you have a work center with four people and it usually takes two hours to set up the machine in the work center. One of the people becomes ill, so you are left with just three people. With the old functionality, the system would have increased the setup duration to two-and-a- half hours automatically. However, with the new functionality, you can manually set the system so that it maintains the same setup duration of two hours.

PDS

The second PP/DS change refers to PDS, introduced with previous releases. PDS groups bill of materials (BOM) information and routes it in a similar way to the production process model (PPM). Now you can maintain the APO information in R/3 or mySAP ERP Central Component (ECC) before you send it to the APO system. That means you can maintain all of the data in the R/3 or ECC system. In SAP SCM 5.0, follow menu path Logistics>Central Functions>Core Interface APO> Integration Model>Change Transfer>PDS>Change PDS before you integrate PDS with R/3 or ECC to add or change data in PDS (Figure 1).

Figure 1

New transaction for PDS maintenance

Planning and Scheduling Heuristics

Planning and scheduling heuristics are responsible for getting answers to planning scenarios, and they are the heart of most PP/DS processes. Table 1 shows the number of PP/DS heuristics included with SAP SCM 5.0, compared with previous releases. SAP incorporated 12 new heuristics that provide new capabilities and enhanced many of the old ones. Some examples of these algorithms, or problem-solving techniques, include material requirements planning (MRP) execution, standard lots planning, scheduling of operations, bottom-up or bottom-down scheduling, and determining critical paths. The new heuristics include new explosion, extended backward scheduling, and capacity push.

New Explosion

Follow menu path IMG>SCM>APO>Supply Chain Planning>PP/DS>Heuristics>Maintain Heuristic (Figure 2). This heuristic introduces functionality that allows the planner to decide if component changes that require a new BOM explosion should change or retain the operation dates (using the Retain Mode flag) when you re-explode an order. For instance, when you change a component in the BOM, you must re-explode the order so the system adds the new component to the order components. In the past, this change also implied a rescheduling of the order operations, which could cause the system to lose any manual changes you made. You can control this behavior with this new setting.

Figure 2

New Explosion heuristics

Extended Backward Scheduling

This heuristic provides an alternative to the optimizer tool when you want to obtain a finite result after planning. It provides a feasible finite plan by performing a backward scheduling of operations. It starts to schedule order operations on operation due dates and accounts for free capacity of resources, alternative resources, and order priorities. For example, you can use it to analyze capacity problems after an infinite MRP. It’s not as complex as the optimizer tool and allows the planner to check if the resources are overloaded. Although the solution is not optimal for scheduling, it can give the planner a quick view of the current capacity situation with a first finite solution. Short- term scheduling still is required because extended backward scheduling cannot provide a well-sequenced solution.

Capacity Push

In many cases after scheduling, free time slots exist in the resource capacity, which provide an undesired low-usage level, especially in consumer product companies. You can use the new capacity push heuristic to fill the available gaps to improve resource usage. For example, some companies require that a resource work 100% of the available time. You can use this heuristic to fill the gaps when the resource has a workload of less than 100%. This heuristic covers the gaps either by creating new production orders or changing production order size by extending existing orders forward or backward (Figure 3).

Figure 3

Heuristic setting

Resource Planning Table

The new resource planning table offers an alternative to the Detailed Scheduling Planning Board (DS Planning Board), a graphical scheduling tool in PP/DS based on a Gantt diagram for resource planning. With the resource planning table, you work with buckets (days) in a spreadsheet interface. Access this new tool via menu path APO > Production Planning > Interactive Production Planning > Detailed Scheduling > Resource Planning Table. In the resource planning table, the capacity planner can schedule operations based on the capacity- balancing information included in the Resource Planning Table screen (Figure 4).

Figure 4

New resource planning table

From the selection area on the left side of the screen, the planner can navigate a list of resources, execute a scheduling heuristic, or check changed objects. The information area on the right side of the screen provides a detailed view of the current capacity situation that shows the Resource Utilization and Available Capacity as well as capacity discontinuations such as Fixing Intervals or Downtime. Additionally, icons on the screen facilitate the navigation to other transactions. SAP also added a similar resource pool sub-screen to the DS Planning Board.

Optimization Improvements

Optimization in PP/DS introduces several functionalities, such as order prioritization, compact scheduling of order operations, and the explanation tool added to the available optimizer tool.

Order prioritization: With order priorization, you can give production orders higher priority over planned orders. This is useful when you have a mix of both types of orders and you want to give temporary priority to the production order to meet order requests. The planned order typically has lower priority during scheduling because it is a planning object, whereas the production order is an approved document to start the production process.

Compact scheduling of order operations: In previous versions, optimization provided a sufficient solution for the order operations along finite resources. However, the total lead time or make span (the overall completion time for an order) determined by the rest of operations was not ideal. Compact scheduling reduces the time intervals between the activities, which reduces the lead time and, implicitly, two other important business parameters: storage cost and wait time.

Explanation tool: Traditionally, the optimizer tools have been compared to a “black box,” where mathematical algorithms solve a complex problem sometimes with limited understanding of the final solution. You start with a problem plus guiding parameters and then you get a solution. What happens when the algorithms execute? That’s what the explanation tool tries to answer. When you click on the explanation icon , the Explanation Log screen appears with information about what occurs during the execution (Figure 5).

Figure 5

New explanation tool for SCM optimizers. This is an example of a PP/DS optimizer.

For instance, the planner can refer to an explanation of an unexpected delay and react appropriately based on this information. The Explanation Log screen provides an overview of the different parameters that the optimizer tool considers. In Figure 5, you can see delayed resources or products by clicking on the corresponding tabs. These tabs provide information about the results. Based on this information, planners can execute the optimizer tool with new parameters if the result is unacceptable, or they can change the result manually.

Process Chains

With SAP SCM 5.0, SAP extends process chains to PP/DS. This provides more flexibility when a complex chain of jobs is required. You can create parallel paths or decision points with OR and AND statements, in comparison to a linear path with standard jobs A?B?C. Follow menu path APO>Production Planning>Automated Production Planning and optimization>Maintain Process Chain to access the process chain functionality. As shown in Figure 6, this graphical tool defines steps.

Figure 6

Steps in a process chain definition

PP/DS also includes enhancements that affect other areas, such as block planning with a separate block basis definition transaction, and easier block maintenance — two processes related mainly to the steel industry. I’ll cover this and other enhancements related to specific industries in a future article.

Adolfo Menéndez Fernández

Adolfo Menéndez Fernández is the application architecture manager at Repsol in Madrid. Previously, he worked at SAP Consulting Spain as the logistics consulting manager. He studied at the University of Oviedo, where he earned an electronic engineering degree. He is a certified SAP consultant in supply and demand planning (SNP and DP), order fulfillment (Global Available-to-Promise), production planning and detailed scheduling (PP/DS), as well as procurement and materials management (MM). Adolfo has more than 10 years of SAP implementation experience in the consumer product goods, pharmaceutical, automotive, furniture, textile, chemical, oil & gas, and steel industries using SAP ERP logistic modules (including PP, MM, and sales and distribution [SD]) as well as SAP SCM (DP, SNP, and PP/DS). He is APICS certified in Production and Inventory Management (CPIM).

You may contact the author at asturiasadolfo@yahoo.com.

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