TML Groups, TMLs, and Measurements

Field	Data Type	Description	Behavior and Usage
Comments	Text	Stores comments.	None
Corrosion Group	Character	Specifies a system level identifier.	The value in this field appears as text following the TML Group ID.
Description	Character	Specifies a short description of the TML Group.	None.
Drawing Number	Character	Specifies a unique ID for the Isometric Drawing, PFD or P&ID.	The value in this field helps the inspector identify where the TML Group is located on an asset.
Line Class	Character	Specifies a class (Class 1, Class 2, Class 3, or Injection Point) that is used to determine inspection intervals based on API 570.	This field is relevant only to Piping assets.
Material Grade	Character	Specifies a Material Grade for the TML Group.	The list of valid values for this field comes from the Materials of Construction family Used for determining Allowable Stress.
Material Specification	Character	Specifies a Material Specification for the TML Group.	The list of valid values for this field comes from the Materials of Construction family Used for determining Allowable Stress.
Material Type	Character	Specifies a Material Type for the TML Group.	The list of valid values for this field comes from the Materials of Construction family Used for determining Allowable Stress.
Operating Pressure	Number	Specifies an Operating Pressure for the TML Group.	The value in this field should be less than the Design Pressure of the component.
Operating Temperature	Number	Specifies an Operating Temperature for the TML Group.	The value in this field should be less than the Design Temperature of the component.
System Type	Character	Specifies a classification for a TML Group (i.e., Floor of a Tank).	None
TML Group ID	Character	Specifies a unique ID for the TML Group.	The value in this field is populated automatically when the TML Group is created.

Thickness Measurement Location records contain various fields that store information to identify a TML. When you create a new TML, you will need to supply information in some of these fields. The values in other fields will be populated or calculated automatically based on other values in the TML and related values.

Field	Data Type	Description	Behavior and Usage
Access	Character	Specifies a special requirement (Man Lift, Ladder, or Scaffold) for how a location must be accessed.	A value should be selected in this field when the TML is created, but can be modified later.
Additional Thickness	Number	Specifies the thickness that is over that which is required to prevent loss of containment plus corrosion allowance.	None.
Allowable Stress	Number	Specifies a value that represents the maximum amount of pressure that can safely be withstood at a given TML.	This field is enabled only if the Override Allowable Stress check box is selected. Otherwise, this field is disabled and populated automatically.
Apex Angle	Number	The angle of any conical section of the asset.	The value in this field is used for conical T-Min calculations.
Code Year (Allowable Stress Lookup)	Character	Specifies the year in which the Design Code was defined or updated.	This field appears as a list retrieved from the Piping Stress, PV Stress or Tank Stress reference table based on the value in the Design Code field. The value in this field is used to populate the Allowable Stress field.
Code Year (T-Min Formula)	Character	Specifies the year in which the Design Code was defined or updated.	The Code Year (T-Min Formula) field is populated with a list of years that exist in Thickness Monitoring Rules Lookup records and correspond to the value in the Design Code field in the TML. The value in the Code Year (T-Min Formula) field is used for determining which formula will be used for calculating the T-Min and Maximum Allowable Working Pressure values.
Component Type	Character	Specifies the type of component being inspected.	The value in this field is used to populate the Allowable Stress field.
Corroded Area Columns	Number	Specifies the number of columns in the corroded area grid.	The number of cells in the corroded area grid, as determined by the number of rows and columns, determines how many measurement values will be recorded for the area.
Corroded Area Length	Number	Specifies a value that indicates the length of the corroded area in inches.	Together, the Corroded Area Length and the Corroded Area Width represent the overall size of the corroded area.
Corroded Area Rows	Number	Specifies the number of rows in the corroded area grid.	The number of cells in the corroded area grid, as determined by the number of rows and columns, determines how many measurement values will be recorded for the area.
Corroded Area Width	Number	Specifies a value that indicates the width of the corroded area in inches.	Together, the Corroded Area Length and the Corroded Area Width represent the overall size of the corroded area.
Corrosion Allowance	Number	Specifies the additional thickness built in by design to allow for a specific expected corrosion rate and usable life of the asset.	The value in this field is used to determine the remaining life of the asset.
Course Height	Number	Specifies the height of each shell course on an AST.	The value in this field allows the user to calculated the static head pressure for each shell course and thus the minimum allowable thickness needed.
Course Number	Number	Specifies the shell course on an AST being inspected or to which the TML is assigned.	For Tanks of the type Welded Shell, the value in this field is used to calculate the value in the Allowable Stress field.
Design Code	Character	Specifies a design code associated with the TML that is used for calculating T-Min.	This field appears as a list that is populated by the DSCD System Code Table. The value in this field is used to filter the list of values that appear in the Code Year (Allowable Stress Lookup) field. It is also used to determine the equipment type of a given Thickness Measurement Location. The MI_ASSET_TYPE System Code Table contains references to System Codes in the DSCD System Code Table.
Design Factor	Number	Specifies a factor used to calculate T-Min.	This field is a consideration of the design metal temperature (based on ambient temperatures), the maximum design temperature, the design specific gravity, the corrosion allowance (if any), and the seismic factor. The value in this field must be between 0 and 1. It will be rounded to 2 decimal places. The value in this field is used as an input for the T-Min Calculator only when Design Code is set to B31.8.
Design Pressure	Number	Specifies the maximum pressure at the TML.	This value is taken from the original design documents for the piece of equipment.
Design Temperature	Number	Specifies the maximum temperature at the TML.	This value is taken from the original design documents for the piece of equipment.
Dish Radius	Number	None.	None.
Distance From the Bottom	Number	Specifies a value that indicates how far the TML is from the bottom of the tank.	This field applies only to TMLs that are linked to assets or TML Groups that represent Tanks.
Excluded From Analysis	Boolean	Indicates whether the TML will be excluded from the Corrosion Analysis.	This field is read-only in the Thickness Measurement Location and displays the value that is defined via the Exclude TMLs window. When this check box is selected, the TML will not be used when performing asset corrosion calculations, and the Scheduled Next Inspection Date, Projected T-Min Date, and Estimated Remaining Life for the TML will be set to null. In addition, the corrosion rates for the excluded TMLs will be calculated for the TML Corrosion Analysis, but will not be used to determine a corrosion rate for the Asset Corrosion Analysis. Only members of the MI Thickness Monitoring Inspector Security Group can exclude TMLs from an analysis.
Fill Height	Number	Specifies the normal operating liquid height in the AST.	The value in this field may be used to calculate T-Min.
Floor Plate has Detection?	Boolean	Indicates whether or not the AST has a means to detect a leak.	The value in this field may be used to extend the recommended inspection intervals.
Floor Plate has Reinforced Lining?	Boolean	Indicates whether or not the AST has a lined and/or reinforced floor.	The value in this field may allow the user to specify a lower T-Min.
Head Diameter	Number	Specifies the diameter of a circular or cylindrical Head.	The value in this field is used for calculating T-Min.
Inside Diameter	Number	Specifies the diameter of a circular or cylindrical asset, measured using the inside wall.	The value in this field is used for calculating T-Min.
Inside Radius	Number	Specifies the radius of a circular or cylindrical asset, measured to the inside wall.	The value in this field is used for calculating T-Min.
Inspection Sequence Number	Number	Specifies a value that indicates the order in which a given TML will be inspected with respect to the other TMLs linked to the same asset or TML Group.	This field is used only to facilitate TML-based inspection workflows, and is not used in any calculations.
Insulated Flag	Boolean	Indicates whether the asset or TML Group is insulated at the TML.	This check box should be selected if the equipment is insulated. This field is for reference only. It does not have any affect on calculations.
Is Corroded Area?	Boolean	Indicates whether the TML represents a corroded area rather than a specific, corroded location.	When this check box is selected, the values in the Corroded Area Columns and Corroded Area Rows fields will create a corroded area "grid" that you will use for recording measurement values. When this check box is selected, measurement values will represent the thickness of the entire area rather than the thickness of a specific location.
ISO Drawing Number	Character	Specifies a unique ID for the Isometric Drawing, PFD or P&ID.	This will help the inspector identify where a TML is located on an asset.
Joint Factor	Number	None.	None.
Knuckle Radius	Number	None.	None.
Location	Character	Specifies the location of the TML on the asset or component.	This field used to provide a description of the location on the asset or component. When creating a new TML, you should type a description that will help you and others locate this TML.
Material Grade	Character	Specifies the grade of material used for the TML.	This field appears as a list that is filtered based on the value in the Material Specification field as specified in the Piping Stress, PV Stress, or Tank Stress reference table. The value in this field is used to populate the Allowable Stress field.
Material Specification	Character	Specifies the industrial specification of the material used for the TML.	This field appears as a list that is filtered based on the value in the Design Code field as specified in the Piping Stress, PV Stress, or Tank Stress reference table. The value in this field is used to populate the Allowable Stress field.
Material Type	Character	Specifies the type of material used for the TML.	This field is used to provide a description of material used at the location on the asset or component.
Maximum Operating Fill Height	Number	Specifies the maximum fill height for the AST.	The value in this field is used for calculating T-Min on an AST.
Mechanical Allowance	Number	None.	None.
Minimum Tensile Strength	Number	None.	None.
Minimum Thickness	Number	Specifies the T-Min value for the TML, which is the minimum wall thickness allowed at the specific location. Typically, you will want to replace an asset or component before any of its TMLs reach the minimum thickness.	The value in this field can be entered manually, or it can be calculated on the T-Min Calculator workspace. If this field does not contain a value, a value of 0 will be used in any calculations that use the T-Min value.
Minimum Thickness Type	Character	Specifies how the T-Min value was obtained. This field is populated with one of the following values: Calculated. Nominal. User Defined.	This field is populated automatically only after the Minimum Thickness field has been populated.
Minimum Yield Strength	Number	None.	None.
Nominal Thickness	Number	Specifies a value that is intended to represent the value of the first measurement recorded for a TML, if the base measurement is recorded from a design specification or other published standard.	The value in this field is populated automatically based on a specified Piping Nominal Diameter value. This value is used to create a Nominal Measurement for a piping asset.
Number of Readings	Number	Specifies the number of values that can be entered in the Readings field in Thickness Measurements that are linked to the TML.	This field accepts only whole number, values between 1 (one) and 26. The data entry grid that is available in the Readings field will have a number of rows based on the value in this field.
Outside Diameter	Number	Specifies the diameter of a circular or cylindrical asset, measured using the outside wall.	The value in this field is used for calculating T-Min. The value in this field is populated automatically based on a specified Piping Nominal Diameter value.
Outside Radius	Number	Specifies the diameter of a circular or cylindrical asset, measured to the outside wall.	The value in this field is used for calculating T-Min.
Override Allowable Stress	Boolean	Indicates that the Allowable Stress field has been modified manually.	When this check box is selected, the Allowable Stress field is enabled and a value can be entered manually.
Piping Formula	Character	Specifies the B31.3 piping formula.	The values in this list are populated from the PIPFMU System Code Table. This field controls which B31.3 formula is used for the T-Min calculator.
Piping Nominal Diameter - DN	Number	Specifies a Nominal Diameter for piping.	DN (Nominal Diameter) data is considered a dimensionless designator, meaning that it does not have an assigned unit of measure and is determined by ASME specifications. The value in this field is used to populate fields for Piping Nominal Diameter. When you select a value for either the Piping Nominal Diameter - NPS or the Piping Nominal Diameter - DN fields: A list of possible values is generated for the Schedule field in the Piping section of the TML datasheet. After a value is selected for the Schedule field, the Pipe Properties reference table populates the Nominal Thickness and the Outside Diameter fields in the Design General section of the TML datasheet.
Piping Nominal Diameter - NPS	Number	Specifies a Nominal Pipe Size for piping.	NPS (Nominal Pipe Size) considered a dimensionless designator, meaning that it does not have an assigned unit of measure and is determined by ASME specifications. The value in this field is used to populate fields for Piping Nominal Diameter. When you select a value for either the Piping Nominal Diameter - NPS or the Piping Nominal Diameter - DN fields: A list of possible values is generated for the Schedule field in the Piping section of the TML datasheet. After a value is selected for the Schedule field, the Pipe Properties reference table populates the Nominal Thickness and the Outside Diameter fields in the Design General section of the TML datasheet.
Plate Thickness	Number	Specifies the thickness of the plates used to construct an AST.	The value in this field is used for determining nominal thickness for an AST.
Renew Historical Sequence Number	Number	Specifies a value that indicates the number of times a given Thickness Measurement Location has been renewed.	This field is read-only and contains no value if the Thickness Measurement Location has never been renewed.
Schedule	Character	Specifies a piping schedule for the TML.	The value in this field, along with the value in either the Piping Nominal Diameter - ND or the Piping Nominal Diameter - NPS field, uses the Pipe Properties reference table to populate the Nominal Thickness and the Outside Diameter fields in the Design General section of the TML datasheet.
Shell Type	Character	Specifies the geometry of the Shell.	The value in this field is used for calculating T-Min.
Specific Gravity	Number	Specifies the molecular weight of the representative fluid in an AST.	The value in this field is used to calculate: T-Min for an AST. Allowable Stress for tanks of the type, Annular Ring.
Status Changed By	Character	Specifies the name of the GE Digital APM Security User who last changed the value in the Status Indicator field.	This field is always disabled. This field is populated automatically whenever the Status Indicator is changed. When a TML is created, this field is populated with the name of the Security User who created it.
Status Changed Date	Date	Specifies the date when the value in the Status Indicator field was last changed.	This field is always disabled. This field is populated automatically whenever the Status Indicator is changed. When a TML is created, this field is populated with the current date.
Status Indicator	Character	Specifies the status of the TML, either Active or Inactive.	This field contains a list of values from the MI STATUS INDICATOR System Code Table. In the baseline GE Digital APM database, the list contains the following values: Active. Inactive. When this value is modified, the Status Changed By and Status Changed Date will be updated automatically. When this field is set to Inactive, values will be deleted from the following fields in the linked TML Corrosion Analysis: Remaining Life. Projected T-min Date. Factor Remaining Life Date. Interval Next Inspection Date. Scheduled Next Inspection Date. Additionally, an inactive TML will not be included in corrosion calculations for an Asset Corrosion Analysis.
Tank Diameter	Number	Specifies the diameter of a tank.	This value is only used for TMLs that are linked to assets or TML Groups that represent tanks or components of a tank. Note: If this field contains a value that is greater than 200, T-Min cannot be calculated for the TML.
Tank Type	Character	Specifies the method of construction for an AST.	The value in this field will be used to calculate T-Min and Allowable Stress.
Temperature Factor	Number	None.	None.
TML Analysis Type	Character	Specifies the type of analysis (UT, RT, or TML). The value used by the Asset Corrosion Analysis to determine how to group the analysis results. A value must be selected in this field when the Thickness Measurement Location is created.	This field is populated with a list of values that are stored in the Inspection Type field in the Corrosion Analysis Settings that are linked to the asset or TML Group to which the TML is linked. In the baseline database, these values are stored as System Codes in the System Code Table CITP (Corrosion Inspection Type). By default, this System Code Table contains three System Codes: UT, RT, and TML. UT (ultrasonic thickness) and RT (radiographic thickness) are provided for customers who want to classify TMLs according to inspection type and then perform calculations on each set. TML is provided for customers who prefer to analyze all TMLs together.
TML Asset ID	Character	Specifies the ID of the Equipment or TML Group record for which the TML is created.	This field is always disabled. This field is populated automatically after the TML is first saved based on the Component ID Field setting for the Equipment or TML Group family.
TML Comment	Character	Stores descriptive information that is not recorded in another field in the TML.	None.
TML ID	Character	Specifies a unique ID for the TML.	The value in this field must be entered when a TML is created, and must be unique.
Vessel Type	Character	Specifies the geometry of the vessel.	The value in this field determines what formula is used when calculating T-Min.

Field	Data Type	Description	Behavior and Usage
Corroded Area Measurement Values	Text	Stores a string of values representing the corroded area thickness measurements.	This field should contain values that have been entered using the corroded area grid only. You should not add or modify values in this field by typing in the field itself.
Historical Sequence Number	Number	Specifies a value that identifies the renewal sequence of the Thickness Measurement.	For example, if a Thickness Measurement Location has three Active Thickness Measurements, when the Thickness Measurement Location is renewed for the first time, the Historical Sequence Number of those three Thickness Measurements will be set to 1 (one). If the Thickness Measurement Location is renewed again, the Historical Sequence Number of any Thickness Measurements that are Active at the time of the renewal will be set to 2 (two).
Instrument Probe	Number	Specifies a value that uniquely identifies the specific probe that was used to collect the measurement value. This field is populated only when a measurement is recorded using a handheld device.	None.
Measurement Comment	Character	Specifies additional information about the measurement.	This field is used to store descriptive information that is not recorded in another field in the Thickness Measurement.
Measurement ID	Character	Specifies the Record ID of the Thickness Measurement.	The value from the Record ID field is copied to the Measurement ID field when the Thickness Measurement is saved. Note that if you modify the ID Template of the Thickness Measurement family and update existing Record IDs, values in the Measurement ID field will not be updated in existing Thickness Measurements until those measurements are saved.
Measurement Status Changed By	Character	Specifies the first and last name of the GE Digital APM Security User who last changed the value in the Measurement Status Indicator field.	This value is updated whenever the value in the Measurement Status Indicator field is changed, either manually or automatically (e.g., when the root Thickness Measurement Location is renewed).
Measurement Status Indicator	Character	Specifies whether the Thickness Measurement is Active or Inactive.	Thickness Measurements that are flagged as Inactive are not used for performing TML Corrosion Analysis calculations.
Measurement Taken By	Character	Specifies the person who recorded the measurement value in the following format: <Last Name>, <First Name> ~ <User ID>	This list in this field contains the names of individual(s) who have been granted the TM Technician role. When you create a Thickness Measurement, if you have been granted the TM Technician role, the value is set by default to your name. You can change the value by selecting another name in the list. The default rule on the Measurement Taken By field specifies that the list is restricted, meaning that you cannot type your own value in the list. If the default rule has been modified to make the list unrestricted, you will be able to type a value in this field, and save it with the Thickness Measurement. The Human Resource records used to populate this field are filtered based on the user's applied sites. If the Human Resource record is not associated with a specific user, the record is included by default.
Measurement Taken Date	Date	Specifies the date that the measurement value was recorded.	This may be the date that the Thickness Measurement was created, or it may be a different date, particularly if the Thickness Measurement was created some time after the measurement was physically recorded.
Measurement Value	Number	Specifies the value, in inches, for a given thickness measurement.	The Measurement Value represents the thickness of the asset or component at the TML on the Measurement Taken Date. The Measurement Value can be a reading that was taken physically or that was recorded based upon a design code or specification. In the baseline TM product, the Measurement Value field is populated automatically with the value in the Uncorrected Measurement field.
Measurement Verified	Character	Specifies whether the Measurement Value has been manually verified.	This field is populated with a list of System Codes in the MI YES System Code Table. After the value in the Verify Measurement field has been set to Yes, this field should be set to Yes to indicate that the measurement data in question has been validated and corrected if needed.
Nominal	Boolean	Indicates whether the measurement was taken physically (the check box is not selected) or recorded from another source, such as a published design specification (the check box is selected).	All Nominal Thickness Measurements will be set automatically to Inactive after two, subsequent Actual Thickness Measurements have been created. Thickness Measurements that are marked as Inactive will not be used for performing TML Corrosion Analysis calculations. This means that after two or more Actual Thickness Measurements exist, Nominal Thickness Measurements will no longer be used in calculations.
Readings	Character	Specifies values that represent the readings that were collected for a given thickness measurement.	The number of values that can be recorded in the Readings field corresponds to the value in the Number of Readings field in the Thickness Measurement Location to which the Thickness Measurement is linked. The Readings field provides access to an editable grid that contains one row per reading value that can be entered. After values have been entered in to the Readings field in a given Thickness Measurement , a calculation will be performed to populate the value in the Uncorrected Measurement field in that same measurement. The calculation that is performed is determined by the Application Settings that have been defined for measurement readings.
Readings Pass/Fail	Character	Specifies a value that indicates whether the values in the Readings field passed or failed evaluation based upon the Reading Tolerance setting.	This field is populated with a list of System Codes in the MI PASS FAIL ONLY System Code Table.
Status Changed Date	Date	Specifies the date that the value in the Status Indicator field was last changed.	This field is updated automatically whenever the value in the Status Indicator field changes.
Temperature	Number	Specifies the temperature at which the measurement value was recorded.	This is an optional field that, by default, stores the value entered by the user. This field is provided so that custom rules can be developed, if desired, to allow for a calculation that will adjust the measurement value based upon the temperature at which the reading was taken.
Uncorrected Measurement	Number	Specifies a value that is the result of the calculation that was performed against values in the Readings field.	The Uncorrected Measurement field is meant to serve as an intermediate storage location between the Readings and Measurement Value fields. If desired, you can create custom rules for the Measurement Value field so that the Uncorrected Measurement value is adjusted based on additional factors and the result of that calculation becomes the value in the Measurement Value field.
Verify Measurement	Character	Specifies a value that indicates whether the value in the Measurement Value field requires manual verification based upon the Allowable Measurement Variance and/or Corrosion Rate Variance validation.	This field is populated with a list of System Codes in the MI YES NO System Code Table.