Class CUIRiskAssessment

java.lang.Object

neqsim.process.mechanicaldesign.designstandards.CUIRiskAssessment

All Implemented Interfaces:

Serializable

public class CUIRiskAssessment
extends Object
implements Serializable

Corrosion Under Insulation (CUI) risk assessment per API 581 / NORSOK M-501.

Provides temperature-based susceptibility screening, material and insulation type compatibility checks, and inspection interval recommendations following industry best practice.

CUI is one of the leading causes of unplanned shutdowns in process plants. The risk depends primarily on operating temperature, insulation type, coating system, and environment.

References:

• API 581: Risk-Based Inspection Methodology (CUI module)
• API 583: Corrosion Under Insulation and Fireproofing
• NORSOK M-501: Surface preparation and protective coating
• EFC Publication 55: CUI Guidelines

Version:

1.0

Author:

esol

See Also:

• Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	CUIRiskAssessment.CUIRisk	CUI risk level enumeration.
static enum	CUIRiskAssessment.InsulationType	Insulation types and their CUI susceptibility.

Field Summary

Fields

Modifier and Type	Field	Description
private static final long	serialVersionUID	Serialization version UID.

Constructor Summary

Constructors

Constructor	Description
CUIRiskAssessment()

Method Summary

Modifier and Type	Method	Description
static CUIRiskAssessment.CUIRisk	assessRisk(double operatingTempC, boolean isStainlessSteel, CUIRiskAssessment.InsulationType insulationType, double coatingAge, boolean isMarineEnvironment)	Assess CUI risk based on operating temperature per API 581 screening criteria.
static double	estimateRemainingLife(double originalThicknessMm, double currentThicknessMm, double yearsInService)	Estimate remaining corrosion allowance based on CUI conditions.
static boolean	isInsulationSuitable(CUIRiskAssessment.InsulationType insulationType, double operatingTempC)	Check whether selected insulation type is appropriate for the operating temperature.
static int	recommendedInspectionIntervalYears(CUIRiskAssessment.CUIRisk risk)	Recommend inspection interval based on CUI risk level.
static List<String>	recommendedInspectionMethods(CUIRiskAssessment.CUIRisk risk)	Return recommended inspection methods for CUI detection.
static double	temperatureRiskScore(double operatingTempC, boolean isStainlessSteel)	Calculate temperature-based risk score per API 581 / API 583 guidance.

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

serialVersionUID

private static final long serialVersionUID

Serialization version UID.

See Also:

• Constant Field Values

Constructor Details

CUIRiskAssessment

public CUIRiskAssessment()

Method Details

assessRisk

public static CUIRiskAssessment.CUIRisk assessRisk(double operatingTempC,
 boolean isStainlessSteel,
 CUIRiskAssessment.InsulationType insulationType,
 double coatingAge,
 boolean isMarineEnvironment)

Assess CUI risk based on operating temperature per API 581 screening criteria.

Carbon steel is most susceptible to CUI in the range -4 C to 175 C (25 F to 350 F). The highest risk zone is 80-120 C where aqueous corrosion and wet-dry cycling are most aggressive.

Parameters:

operatingTempC - operating temperature in Celsius

isStainlessSteel - true if material is austenitic stainless steel (300-series)

insulationType - insulation type

coatingAge - years since last coating application

isMarineEnvironment - true if offshore or coastal

Returns:

CUI risk level

temperatureRiskScore

public static double temperatureRiskScore(double operatingTempC,
 boolean isStainlessSteel)

Calculate temperature-based risk score per API 581 / API 583 guidance.

Parameters:

operatingTempC - operating temperature in Celsius

isStainlessSteel - true if austenitic stainless steel

Returns:

risk score (0 = negligible, 1 = low, 3 = high, 5 = very high)

recommendedInspectionIntervalYears

public static int recommendedInspectionIntervalYears(CUIRiskAssessment.CUIRisk risk)

Recommend inspection interval based on CUI risk level.

Parameters:

risk - CUI risk level

Returns:

recommended inspection interval in years

recommendedInspectionMethods

public static List<String> recommendedInspectionMethods(CUIRiskAssessment.CUIRisk risk)

Return recommended inspection methods for CUI detection.

Parameters:

risk - CUI risk level

Returns:

list of recommended inspection technique names

isInsulationSuitable

public static boolean isInsulationSuitable(CUIRiskAssessment.InsulationType insulationType,
 double operatingTempC)

Check whether selected insulation type is appropriate for the operating temperature.

Parameters:

insulationType - insulation type

operatingTempC - operating temperature in Celsius

Returns:

true if insulation type is suitable for the temperature

estimateRemainingLife

public static double estimateRemainingLife(double originalThicknessMm,
 double currentThicknessMm,
 double yearsInService)

Estimate remaining corrosion allowance based on CUI conditions.

Parameters:

originalThicknessMm - original wall thickness in mm

currentThicknessMm - measured current wall thickness in mm

yearsInService - years in service

Returns:

estimated remaining life in years at current corrosion rate, or Double.MAX_VALUE if no measurable thinning