Define the Dynamic Sampling Size for an Inspection Definition

Dynamic Sampling Size for an Inspection Definition is used to adjust the number of units inspected based on real-time quality performance and production conditions. In cases where the quality performance deteriorates or during critical production phases, you can tighten, that is, increase the number of units inspected. If the quality performance is stable and within acceptable limits, you can continue with a normal sampling size. If the quality performance is consistently high, the process is stable, and the risk of defects is low, you can reduce the sampling size, that is, decrease the number of units inspected.

Dynamic Sampling Guideline defines the sample size to be used for different inspection scenarios of Normal, Tightened, and Reduced inspections. Switching Rules Guideline defines the rules that must be followed during the inspection for switching between the different inspection scenarios. You can assign these guidelines to an entire Control Plan or to an individual Inspection Definition. When you assign Dynamic Sampling Guideline and Switching Rules Guideline to a Control Plan, and submit the Control Plan to the Assign Guidelines to the Control Plan structure workflow, the same guideline is set for each individual Inspection Definition of the Control Plan. You can also define Dynamic Sampling Guideline and Switching Rules Guideline for each Inspection Definition separately.

Generally, the lot size is defined for a part during the actual production, and it varies while executing the production. If you define a lot size value for a Control Plan, and the Inspection Definition is assigned Dynamic Sampling Guideline and Switching Rules Guideline, then the Dynamic Sample Size values are automatically calculated and displayed in the Overview tab of the Inspection Definition.

Note

By default, the following guidelines are available:

• Dynamic Sampling Guideline: Inspection Sampling: ISO 2859-1

• Switching Rules Guideline: Switching Rule: ISO 2859-1

Procedure

1. To create a Dynamic Sampling Guideline, do the following:

In Explorer, navigate to the folder where you want to create the Dynamic Sampling Guideline.

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New Add.

In the Add panel, from the Type list, select Dynamic Sampling Guideline.

Specify a name and description for Dynamic Sampling Guideline, and click Add.

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Edit  > Start Edit .

In the Dynamic Sampling for Inspection Scenarios section, click Add .

Create a row with values for Minimum Lot Size, Maximum Lot Size, Normal, Tightened, and Reduced.

You can define the minimum and maximum lot size, and the sample size for a normal, tightened, and reduced inspection. Example If you have a lot size of 75, it comes in the range of 50 as the minimum lot size and 100 as the maximum lot size. So, for a lot size of 75, the sample size can be 20 for a normal inspection, 25 for a tightened inspection, and 8 for a reduced inspection.

Click Add to create additional rows and complete the Dynamic Sampling Guideline.

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Edit Save Edits .

2. To create a Switching Rules Guideline, do the following:

In Explorer, navigate to the folder where you want to create the Switching Rules Guideline.

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New Add.

In the Add panel, from the Type list, select Switching Rules Guideline.

Specify a name and description for Switching Rules Guideline, and click Add.

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Edit  > Start Edit .

In the Switching Rules for Inspection Scenarios section, click Add .

Create a row with values for Rule No, Inspection Type, Accepted Lots, Changed to Rule Number, Not Accepted Lots, and Changed to Rule Number.

You can define which rule must be applied when you find acceptable and unacceptable lots in the inspection process. Example For a normal inspection, if you find 30 acceptable lots, then switch to rule 3: Reduced inspection. If you find 2 rejected lots, then switch to rule 2: Tightened inspection. For a tightened inspection, if you find 5 acceptable lots, then switch to rule 1: Normal inspection. If you find 5 rejected lots, then switch to rule 4: Discontinue inspection.

Click Add to create additional rows and complete the Switching Rules Guideline.

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Edit Save Edits .

3. To assign Dynamic Sampling Size to all Inspection Definitions of the Control Plan, do the following:

In the folder where you created the Control Plan, select and open the Control Plan that you want to edit.

Click Edit , and select a dynamic sampling guideline from the Dynamic Sampling Guideline list.

From the Switching Rules Guideline list, select a switching rule guideline.

Type the lot size for the Control Plan in the Lot Size box, and click Save .

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Manage > Submit to Workflow.

In the Submit to Workflow panel, from the Template list, select the Assign Guidelines to the Control Plan structure workflow.

Accept the default workflow Name or type your own.

Enter a Description for the new workflow.

Click Submit.

A notification is displayed in the Alerts panel when Dynamic Sampling Size is calculated and assigned to all Inspection Definitions in the Control Plan. You can also edit the individual Inspection Definitions to use different values for Dynamic Sampling Guideline and Switching Rules Guideline, and calculate the Dynamic Sampling Size for the new values.