About the Types of Corrosion Analyses

In addition to assets, Asset Corrosion Analyses are also created and linked automatically to any TML Group that is included in the Corrosion Analysis for an asset.

An Asset Corrosion Analysis represents a summary of the calculations that are stored in the TML Corrosion Analysis for each TML linked to a single asset or TML Group. Using an Asset Corrosion Analysis, you can determine the overall corrosion of an asset and make decisions about the actions that should be taken based upon the analysis results.

An Asset Corrosion Analysis represents:

• An Equipment record or TML Group.

• All the TMLs of a given TML Analysis Type (UT, RT, or TML) that are linked to the Equipment record or TML Group.

• All the Thickness Measurements that are linked to the TMLs.

• All the calculations that are performed based upon the values in the TMLs and Thickness Measurements.

Because baseline Thickness Monitoring supports the use of three TML Analysis Types (UT, RT, and TML), each Equipment record or TML Group can have up to three Asset Corrosion Analyses linked to it.

The TML Analysis Types UT and RT are provided for customers who want to classify TMLs according to measurement-collection method (ultrasonic thickness or radiographic thickness), and then perform calculations on each set of TMLs.

The TML Analysis Type TML is provided for customers who do not want to classify TMLs according to measurement-collection method, and instead prefer to analyze all TMLs together. Typically, you will use either both UT and RT, or only TML. Most customers will not use all three. Therefore, Equipment records and TML Groups will usually have either one or two Asset Corrosion Analyses linked to them.

Each TML Corrosion Analysis stores summary information and calculation results that are determined using the Thickness Measurements linked to TMLs.

When TMLs are linked to an asset or TML Group, the TML Corrosion Analyses linked to the TMLs will provide the information to the Asset Corrosion Analysis, which serves as an overview of the corrosion information gathered for each TML.

While the Asset Corrosion Analysis provides a useful summary of the corrosion status of a given asset, if you want to get a more detailed perspective of the corrosion of the equipment, you will need to examine the individual TML Corrosion Analyses. Because values in the Asset Corrosion Analysis are determined using values stored in individual TML Corrosion Analyses, you may need to review the TML Corrosion Analyses in order to interpret the data in a Corrosion Analysis Summary.

In most cases, the values stored in the Asset Corrosion Analysis represent calculations that are performed for TMLs using values in the TML Corrosion Analyses, which have been summarized based on settings defined for the analysis. For example, in the Corrosion Analysis Settings, you can specify whether you want the Asset Controlling Corrosion Rate to be the maximum corrosion rate for all TMLs, or an average of the corrosion rates that have been calculated for the TMLs. In other words, Asset Corrosion Analysis values are typically not unique to the Asset Corrosion Analysis itself.

In Corrosion Analyses that include both assets and TML Groups, the Asset Corrosion Analysis will contain information that is derived from the information stored in the Asset Corrosion Analyses for the assets and the TML Group.

For example, consider a piping circuit that contains three piping lines where the information for the piping circuit is stored in four records:

• Equipment A - Piping Circuit

• TML Group 1 - Piping Line 1
• TML Group 2 - Piping Line 2
• TML Group 3 - Piping Line 3

Additionally, assume that TMLs exist for each TML Group, and each of those TMLs has its own TML Corrosion Analysis. In this situation, each TML Group will have its own Asset Corrosion Analysis that stores summary information about the calculations stored in the corresponding TML Corrosion Analyses. The asset will also be linked to its own Asset Corrosion Analysis that stores summary information that is derived from the information in the analyses that are linked to each TML Group.