Defining formulas

Define generic formulas to establish any calculation that produces a minimum or maximum critical value for an inspection point aspect combination or any calculation with entered monitored data, and then identify where the system executes those formulas. First, define the actual formula, and then define parameters used within the formula. The system calculates formulas with SQL statements defined for the parameters used in the formula.

To define formulas:

  1. Open the Formula IDs form.
  2. Click New Record.
  3. Formula ID—Enter a unique code identifying the formula, and then enter a description of the formula in the adjacent field.
  4. Class—Enter the class of the formula. The system automatically populates Class Org.
  5. Formula—Enter the actual formula using codes to identify parameters. For example, to calculate minimum allowable thickness (MAT) for a cylindrical shell using design pressure (DP), actual outside diameter (OD), and nominal design stress (NDS), enter the following equation:
    $MAT = $DP * $OD/ (2 * $NDS + $DP)
    Note: All parameters must have a dollar sign prefix ($).

    To create parameters immediately, click Verify Parameters. The system verifies that the parameters exist. If they do not exist, the system asks if you want to create a new parameter. Click Yes. The system inserts a new parameter for the formula and updates the Parameters list on the Parameters page.

    To perform a validation of a formula, click Validate Formula.

    Depending on your system configuration, Validate Parameters and Validate Formula may not be displayed. Contact your system administrator for additional information.

  6. Click Save Record.