Creating Nonconformance Groups and Codes

In the bicycle manufacturing example, we have a three-step manufacturing process. During assembly, the operator documents minor defects, such as scratches on the surface of the bicycle frame, by assigning a nonconformance (NC) code. The quality assurance team can then use a report to get an overview of these minor defects and implement appropriate countermeasures if necessary.

The manufacturing process ends with a thorough in-process quality inspection. If the inspection reveals any issues, the operator can record the specific deviation as a nonconformance. In our example, the shop floor operator has identified that the tire pressure is too low. Therefore, it is necessary to halt the production process for the corresponding bicycle until the root cause of this defect is determined. When logging the NC code for the bicycle, the operator can provide additional information such as comments, pictures, immediate actions, and so on. They can then decide what should be done next with the bicycle, such as performing a local repair or routing it to other specialized analysis-repair stations. Once the analysis and repair are completed, the bicycle can return to its original manufacturing routing and the assembly process can resume.

The nonconformance functionality in SAP Manufacturing Execution offers a mechanism to log, track, and handle failed or defective parts or assemblies. It enables you to:

• Document the nonconformance management process using a closed loop system.
• Speed up the disposition of nonconforming parts or material.
• Ensure that designated resources receive nonconformance work tasks and provide traceability.

During a test or inspection, it is possible to find a nonconformance for a product. It is important to detect and track the nonconformance to maintain the quality of the product high and minimize costs associated with quality and rework.

The initial detection of a nonconformance may not identify the cause of the failure. For instance, when testing the bicycle breaks, the shop floor operator identifies that the wheels are not stopping as expected. The initial detection of the nonconformance would identify that the breaks aren't working, but not the reason for this.

Once the nonconformance has been detected, it can be further analyzed to understand what the actual defect is to resolve the incident.

Additional analysis may be necessary to determine the reason for the nonconformance. For instance, in the previous example, if a the bicycle wheels aren't breaking as expected, a technician can conduct a more thorough examination and discover that there is a disconnected wiring in the breaking system. The follow up nonconformance should be logged against the original nonconformance incident, indicating the potential root cause of the original failure.

Once the technician determines the root cause, they can now perform the necessary actions to correct the defect. For example, the technician would choose to reconnect the disconnected wiring . This repair action would then be logged as part of the chain of nonconformances to track the successful resolution and close the loop on the nonconformance. The repair action allows the unit to be recognized as work in process of good quality.

During bicycle manufacturing, it is common to identify nonconformances related to paint, such as chipping, peeling, and discoloration. For the shop floor operator, it is useful that when logging a nonconformance related to paint, they can find all these nonconformances grouped in a central place.

To begin, you need to define nonconformance groups. These groups help organize the master data by assigning nonconformance (NC) codes to them. By assigning an NC code to a group, you can easily select it during the NC logging process.

In the Manage Nonconformance Groups application, you have the ability to create and configure NC groups.

An NC group and its assigned NC codes are available in all operation activities by default. To restrict their availability to specific operation activities, you can manually assign these operation activities to the NC group. For example, you can choose to assign the NC group only to certain operation activities.

In our example, to manage these nonconformances, you can create an NC group called "PAINT" and assign the corresponding NC codes to it. By assigning the operation activity "PAINT_INSPECTION" to this NC group, the production operator can browse the available NC codes within the PAINT group and choose the appropriate codes to log the nonconformance.

The Production Operator Dashboard (POD) allows users to view the available NC groups and their assigned NC codes. This can be done by using the NC Selection plugin. By doing so, the production operator can easily locate and select the desired NC codes when recording nonconformances.

When a production operator determines that a material being produced does not meet the applicable manufacturing standards, they may choose to assign one or more nonconformance (NC) codes to it. In this process, an NC code can be used to identify the observable symptom that caused the failure. Nonconformance usually includes defects, symptoms, repairs, or root causes.

A nonconformance (NC) code is a set of characters that represents a failure, defect, or repair code indicating that the shop floor control (SFC) does not meet the approved product quality definition. Depending on the system setup or business process, one or multiple NC codes may be used. Assigning an NC code to an SFC usually indicates the following:

• The SFC has minor quality issues and does not comply with quality standards, for example, scratches.
• The SFC has major or critical quality issues, such as a failure, and further analysis is required before the SFC can continue the regular manufacturing process.
• The SFC must undergo special processing steps, such as rework.

Nonconformance Codes are maintained in the Manage Nonconformance Codes application.

NC codes belong to one of the following categories:

• Failure: The type failure is normally set for a primary NC and describes how the SFC does not comply with quality standards, for example device failure. However, a primary NC does not describe the underlying, real defect, or the root cause of the defect.
• Defect: The type defect is typically set for a secondary NC and corresponds to the diagnosis of the quality defect (confirmed defect).
• Repair: Typically set for a secondary of a secondary that is, a tertiary nonconformance. It signifies the process of fixing the quality defect for a specific SFC number.

If the operator logs an NC and additional data needs to be collected, a corresponding data type can be assigned. In the following lesson, more information about NC data types will be provided.

You can determine whether the NC code can be a primary NC code. If not, the NC code can only serve as a secondary NC code.

When the operator logs this NC code in the production operator dashboard (POD), they can determine whether it automatically closes itself and all its parent NC codes. Other NC codes that aren't in the same NC hierarchy aren't closed.

If you have created specific routings to handle nonconformances, you can assign these routings to NC codes. For example, if you assign an NC code to certain routings, when the production operator logs this NC code against an SFC, they can choose to send or disposition the SFC to one of the assigned routings. You can only assign routings of certain types to NC codes, such as Special Routing, NC Routing, or Disposition Function Routing.

The Secondaries tab allows the assignment of a list of secondary NC codes to the primary code. By adding one or more NC codes to the list of secondary codes, you define the hierarchy of nonconformances that can be logged.

The NC code hierarchy illustrates the relationship between the NC codes that operators have logged into the system. For example, the figure demonstrates various scenarios of different complexities.

• In the simplest scenario, an SFC collects only a failure code as a primary NC code. This business scenario is typically selected to document minor defects during the production process for reporting purposes or compliance reasons.
• In a two level hierarchy scenario, an SFC can have a failure code assigned to it at the primary level. It is possible to assign a secondary NC code to the primary NC code. The primary failure code documents the type of nonconformance, such as a confirmed defect, and the secondary NC code is used to document the immediate repair action that the operator performed during the manufacturing process.
• The most complex scenario involves a three level hierarchy. First, the operator assigns a failure NC code to the SFC at the primary level. This code corresponds to the type of defect that is immediately visible to the operator. However, the underlying "real" defect or root cause may only be detected during a comprehensive analysis, which the operator cannot perform. Therefore, the SFC is sent to a specialized analysis-repair work center, where expert personnel conduct an in-depth analysis and identify the "real" defect as a secondary NC code. If the device can be repaired, a corresponding repair action can be documented as a tertiary NC code before the SFC is sent back to the originating work center.

When a user logs an NC code for an SFC, the system graphically displays this hierarchy in the NC data tree in the production operator dashboard (POD). This allows the operator to easily choose one or more NC codes.

The NC Groups tab allows users to assign NC codes to groups for organizing the master data. It is important to note that one NC code can be assigned to multiple NC groups. You create a hierarchy of your NC codes by making them either primary or secondary codes and associating them with each other. You determine the place of an NC code in the hierarchy at its category and the level of granularity you want.