Related Topics:

ALTA Degradation Analysis

Control Panels

Weibull++ Degradation Analysis Folio

Degradation analysis is a technique that uses the performance measurements (degradation measurements) of a product over time to predict the point at which each unit in the sample is expected to fail. This analysis is useful for tests performed on products with very high reliability, where it is not possible to test the products to failure under normal operating conditions.

The Weibull++ degradation analysis folio extrapolates the times at which the amount or level of degradation is serious enough that the unit is considered to be failed. In addition, the folio automatically performs life data analysis on the extrapolated failure times. This allows you to obtain the life characteristics of the product.

The ReliaWiki resources portal has more information on degradation analysis at: http://www.ReliaWiki.org/index.php/Degradation_Data_Analysis.

This topic discusses the following:

Degradation Folio Data Sheet

To add a Weibull++ degradation analysis folio to a project, choose Insert > Folios > Weibull++ Degradation or right-click the Specialized Folios folder in the current project explorer and choose Add Weibull++ Degradation on the shortcut menu.

The following example shows a degradation analysis of two automobile tires, A and B.

 

The data sheet contains the following information:

Control Panel Settings

The Weibull++ degradation folio control panel allows you to configure the analysis settings for the data sheet and view/access the results. It consists of multiple pages, each containing options for performing particular tasks. This topic focuses on the Main page of the Weibull++ degradation folio control panel, which contains the tools you will need to analyze the data set. For more information about control panels in general, see Control Panels.

The Main page includes the following settings:

Tip: If you are not certain which degradation model would provide the best fit for your data, you can use the Degradation Model Wizard to guide you through the selection process.

What's Changed? In previous versions of Weibull++, you used the Associate Specialized Folio tool to transfer the extrapolated data points to a standard folio data sheet in order to perform life data analysis. In the Synthesis version, you can conveniently perform life data analysis calculations within the degradation analysis folio.

When you click the Calculate icon on the control panel, the software extrapolates the points at which the degradation measurements will reach the point of critical degradation. It then performs a separate life data analysis on the extrapolated points based on the settings you have specified in the Life Data Model area.

Note: If the distribution and parameters are associated with a published model, then the model's name will appear as a link at the bottom of the Life Data Results area. Click the link to view the model's properties. For details on how to publish the results as a model, see Publishing Models.

Folio Tools

The folio tools are arranged on the left side of the Main page of the control panel. Use these tools to manage data and experiment with the results of your analysis.

  Calculate extrapolates the points at which the degradation measurements will reach the point of critical degradation (i.e., the times at which the degradation is serious enough that the unit is considered to be failed). The software then performs life data analysis calculations on the extrapolated data points. This tool is also available by choosing Degradation > Analysis > Calculate.

  Plot creates a new sheet in the folio that provides a choice of applicable plot types. This includes the degradation vs. time plot in addition to the life data analysis plots. This tool is also available by choosing Degradation > Analysis > Plot.

  QCP opens the Weibull++ Quick Calculation Pad, which allows you to calculate life data analysis metrics, identical to the calculations you can perform in a Weibull++ standard folio. This tool is also available by choosing Degradation > Analysis > QCP.

  Degradation Model Wizard opens the Degradation Model Wizard, which helps you select the degradation model that best fits your data. This tool is also available by choosing Degradation > Analysis > Model Wizard.

  Distribution Wizard opens the Distribution Wizard, which helps you select the distribution that best fits the data set based on the chosen parameter estimation method (i.e., RRX or RRY). In the degradation folio, the ranking in the Distribution Wizard is based on the life data model. This tool is also available by choosing Degradation > Analysis > Distribution Wizard.

  Change Units opens the Change Units window, which allows you to change the units for the time values in the current data sheet.

 

© 1992-2015. ReliaSoft Corporation. ALL RIGHTS RESERVED.