All inputs that appear in this input section are required unless otherwise specified.

Analysis Code

Select whether to use the code rules from API 579-1/ASME FFS-1 or ASME B31G as the basis for the analysis.

MAWP or MFH Approach

Select whether to manually enter the maximum allowable working pressure (MAWP) or have the program calculate it. Additional inputs will be required to calculate the MAWP. For atmospheric storage tanks maximum fill height (MFH) will be used in place of MAWP. This input only appears for assessments to the API-579 code.

Component Geometry

Select geometry based on the type and shape of the component. This input will automatically be set to piping for assessments to the B31G code.

Basis for Dimensions

Select whether to use nominal or corroded dimensions as the basis for data entry. Nominal dimensions are the original design dimensions; this option should be selected if input is based on original design documentation. Corroded dimensions are the dimensions in the current, corroded state; this option should be selected if input is based on recent measurements.

Damaged region is in the center section of the head

Check this box if the local metal loss is located within the center portion of the head. For elliptical heads this is a section within 0.8D centered on the head centerline. For torispherical heads this is the section in the spherical portion of the head, beyond the knuckle radius. This input will appear only for elliptical and torispherical head geometries.

Elliptical Head Ratio, Rell

Enter the elliptical head ratio, i.e. the ratio of the major to minor axis of an elliptical head. This input will appear only for elliptical heads.

Crown Radius, Cr

Enter the inside radius of the spherical portion of the torispherical head. This input will appear only for torispherical heads.

Corrosion Location

Select whether corrosion is located on the inside or outside. The assessment is not valid when corrosion is present on both the inside and outside diameter.

Internal Design Pressure

Enter the internal design pressure for the component. This input will appear only for pressurized components assessed to the API-579 code.

Maximum Allowable Working Pressure, MAWP

Enter the maximum allowable working pressure (MAWP) of the component. The MAWP should account for any prior uniform metal loss (LOSS) and future corrosion allowance (FCA). This input will appear only for pressurized components assessed to the API-579 code.

Design Fill Height, H

Enter the design fill height (H) of the component. This input will appear only for atmospheric storage tanks assessed to the API-579 code.

Maximum Fill Height, MFH

Enter the maximum fill height (MFH) of the component. The MFH should account for any prior uniform metal loss (LOSS) and future corrosion allowance (FCA). This input will appear only for atmospheric storage tanks assessed to the API-579 code.

Nominal Thickness, tnom

Enter the original component thickness in requested units. This input will appear only if Nominal Dimensions are selected as the Basis for Dimensions.

Prior Uniform Metal Loss Remote from Damaged Region, LOSS

Enter the amount of uniform metal loss away from the local metal loss location at the time of the assessment. This input will appear only if Nominal Dimensions are selected as the Basis for Dimensions.

Nominal Inside Diameter, D

Enter the original inside diameter of the component in requested units. This input will appear only if Nominal Dimensions are selected as the Basis for Dimensions.

Uniform Corroded Thickness Away from LTAs, trd

Enter the current thickness (i.e. corrected for LOSS) of the component away from the localized thinning. This input will appear only if Corroded Dimensions are selected as the Basis for Dimensions.

Uniform Corroded Inside Diameter Away from LTAs, D

Enter the current inside diameter of the component in the area adjacent to the location of metal loss (i.e. corrected for LOSS but not including localized thinning). This input will appear only if Corroded Dimensions are selected as the Basis for Dimensions.

Future Corrosion Allowance Away from Metal Loss, FCA

Enter the allowable future corrosion in the component away from the localized thinning.

Future Corrosion Allowance Local to Metal Loss, FCAml

Enter the allowable future corrosion in the component in the area of localized thinning.

Longitudinal Weld Joint Efficiency, EL

Enter the weld joint efficiency for the longitudinal welds of the component. Enter 1 for components with no longitudinal welds (e.g. seamless pipe). This input will appear only for assessments to the API-579 code on cylindrical components.

Circumferential Weld Joint Efficiency, EC

Enter the weld joint efficiency for the circumferential welds of the component. This input will appear only for assessments to the API-579 code.

Allowable Remaining Strength Factor, RSFa

Enter the allowable remaining strength factor for the component. The recommended value for RSFa per API-579 Part 2 paragraph 2.4.2.2.d is 0.9. Refer to API-579 Annex 2F for guidance on establishing alternative values for RSFa.

Flow Stress Correlation Selection

Select the formula for flow stress from the drop-down list to be used in the assessment. This input will appear only for B31G assessments. Refer to Section 1.7 of B31G for further detail.

Safety Factor

Enter the safety factor for the piping. This input will appear only for B31G assessments.

Current Maximum Operating Pressure, PO

Enter the maximum possible operating pressure for the piping. This input will appear only for B31G assessments. This input is optional. The program calculates the maximum permissible pressure; the program also returns a statement indicating whether or not the component is fit for service if this input is entered.

Specified Minimum Yield Strength at Ambient Conditions, SMYS

Enter the minimum yield strength of the material at ambient conditions per the material specification. This input will appear only for B31G assessments.

Ultimate Tensile Strength of Material at Design Temperature, SUT

Enter the ultimate tensile strength of the material at the design temperature per the material specification. This input will appear only for B31G assessments.

Yield Strength of Material at Design Temperature, SY

Enter the yield strength of the material at the design temperature per the material specification. This input will appear only for B31G assessments or if the “Consider External Pressure” option is selected.