TMLs
About Thickness Measurement Locations (TMLs)
A TML is a specific location on an asset where Thickness Measurement readings are taken and for which various values, including minimum thickness, are calculated. Each asset or TML Group can have multiple TMLs associated with it, which stores identifying information. Thickness Measurements are linked to TMLs, which store readings taken at that location.
About Renewing Thickness Measurement Locations (TMLs)
Renewing TMLs provides a mechanism for optionally recording a new base measurement for a TML and setting all existing Thickness Measurements to Inactive. Additionally, the value that was the Controlling Corrosion Rate for the TML prior to the renewal replaces the Minimum Corrosion Rate value in the associated Corrosion Analysis Settings after the renewal. You can renew Thickness Measurement Locations without adding new measurements.
Details
Generally, you will want to renew TMLs when you replace an asset. For example, if an asset representing a tank is linked to one or more TMLs that have Thickness Measurements, when you replace the tank, you can renew the TMLs to retain the measurement data recorded for the old tank while creating a new base measurement for the new tank. When you do this, you can begin calculating Corrosion Analyses for the new tank.
When you renew a TML:
- In linked Thickness Measurements, if the Measurement Status Indicator field was set to Active prior to the renewal, it will be set to Inactive. In addition, the value in the Measurement Status Indicator Basis will be populated.
- The value in the Historical Sequence Number field in linked Thickness Measurements that were used during that life cycle will be incremented. For example, if the Historical Sequence Number field previously contained no value, indicating that the associated TML had never been renewed, it will now be 1, indicating that the associated Thickness Measurement Location record has been renewed one time.
- The value in the Renew Historical Sequence Number field of the TML will be populated with the largest Historical Sequence Number in the associated Thickness Measurements that were used during that life cycle. For example, assume there are two associated Thickness Measurements that were used during the life cycle. If the Historical Sequence Number of the first measurement is 1 and that of the second measurement is 2, the Renew Historical Sequence Number field in the TML is populated with the value 2. This will keep track of the life cycle for that TML.
- The value in the Minimum Corrosion Rate field in the Corrosion Analysis Settings for the TML is replaced with the current value in the Controlling Corrosion Rate field in the TML.
- The value in the Status Changed By field in the TML will update to reflect the User ID of the Security User who renewed the TML.
- The value in the Status Changed Date field in the TML will change to the current date.
About Moving Thickness Measurement Locations (TMLs)
Under some circumstances, it may be necessary to move TMLs from one asset or TML Group to another. There are two scenarios in which you might perform this task.
Moving TMLs from one Corrosion Analysis to another
You may determine that a TML that was originally linked to one asset or TML Group actually belongs to a different asset or TML Group that is included in a different Corrosion Analysis. In this case, rather than creating a new TML for the correct asset or TML Group, you can relocate the TML.
In this case, you will use Relocate TMLs to select the TML that you want to move and the asset or TML Group to which it will be linked.
Moving TMLs from one TML Group to another in the same Corrosion Analysis
You may determine that a particular subset of existing TMLs actually belong in their own TML Group. If so, you would create a TML Group for the asset, and then move the TMLs to the new TML Group.
In this case, you will use Organize TMLs to move the TMLs from one TML Group to another.
Details
When you move a TML from one asset or TML Group to another:
- The TML ID of the TML you want to relocate cannot be the same as that of a TML that is already linked to the target asset or TML Group.
- The TML that you relocate will now be linked only to the target asset or TML Group that you select via the Has Datapoints relationship.
- The value in the TML Asset ID field of any relocated TML will be updated to reflect the target asset or TML Group.
- Any Thickness Measurements, TML Corrosion Analyses, and Corrosion Analysis Settings that are linked to a TML will remain linked after the TML is relocated.
- The Corrosion Analysis Settings for the relocated TML will inherit the values in the Corrosion Analysis Settings that are linked to the target asset or TML Group, with the exception of the following fields:
- Allowable Measured Variance
- Corrosion Rate Variance
- Default Inspection Interval
- Minimum CR
- You can select TMLs from multiple source assets or TML Groups for a single relocate operation, but you can select only a single target. If you want to relocate TMLs to more than one target asset or TML Group, you will need to perform the relocate procedure multiple times.
- After the TMLs are relocated, all calculations will be updated for the Corrosion Analysis that is associated with the source and target asset or TML Groups.
Access a Thickness Measurement Location (TML)
About This Task
This topic describes how to access a TML via the Analysis Overview workspace for an asset or TML Group. You can also access the Analysis Overview workspace directly for a TML.
Procedure
Filter Thickness Measurement Locations (TMLs)
About This Task
Procedure
Create a Thickness Measurement Location (TML)
Procedure
Results
- The new TML is linked to the record selected in step 1.
- TML Corrosion Analysis Settings are created automatically for the new TML. The values in the TML Analysis Settings are inherited from the analysis settings for the asset or TML Group selected in step 1.
- You can modify the TML by accessing the datasheet.
Configure the Thickness Monitoring Location (TML) Section
About This Task
You can configure the table in the TMLs section by adding or removing fields using the Choose Columns window.
Procedure
Results
- The TML table configuration is saved as a user preference in the APM database.
- The fields added via the Choose Columns window also appear in the following areas:
- The Renew TMLs window
- The Exclude TMLs window
- The Organize TMLs window
- The Relocate TMLs workspace
Copy Thickness Measurement Locations (TMLs)
Procedure
Relocate a Thickness Measurement Location (TML)
About This Task
You can relocate TMLs to move TMLs from a source asset or TML Group to a different target asset, or to a TML Group or subcomponent linked to that target asset. If you need to move TMLs to or between subcomponents linked to the same asset, use the Organize TMLs method.
Procedure
Results
Renew Thickness Measurement Locations (TMLs)
Procedure
Organize Thickness Measurement Locations (TMLs)
About This Task
You can organize TMLs to move TMLs to or between TML Groups and subcomponents associated with the same asset. If you want to move TMLs to another asset, or to a subcomponent of that asset, you should relocate those TMLs.
Procedure
Results
Exclude a Thickness Monitoring Location (TML)
Before You Begin
- Only MI Thickness Monitoring Administrator and members of the MI Thickness Monitoring Inspector Security Group can exclude TMLs from an analysis.
Procedure
Access the TM Quick View Page
About This Task
The TM Quick View page displays a list of TMLs in an asset or TML Group, along with details on the corrosion rate, next inspection date, measurements taken in each month, and so on.
Procedure
Modify TMLs in Bulk
Procedure
Access the TML Trends Graph
About This Task
Procedure
Define Allowable Stress
About This Task
This topic describes how to define the Allowable Stress value for a TML manually. You can also have APM populate the value based on values in a few fields in the TML record. This procedure can be performed before or after you have automatically calculated Allowable Stress for a TML.
Procedure
Calculate Allowable Stress
About This Task
This topic describes how to have APM calculate the value in the Allowable Stress field automatically. You can also define a value manually.
Procedure
Make a Thickness Measurement Location (TML) Inactive
Before You Begin
- When you make a Thickness Measurement Location (TML) inactive, it will be excluded from any future corrosion analysis calculations.
Procedure
Delete a Thickness Measurement Location (TML)
Before You Begin
- When you delete a TML, any linked measurements, Corrosion Analysis Settings, and TM Corrosion Analyses are also deleted.