Weld performance class(CP) • It is performance requirements of the welded joint as defined by the stress category and the safety category of the welded joint. • Note: The weld performance class is abbreviated by “CP” (class of performance).
Weld performance class(CP)It is performance requirements of the
welded joint as defined by the stress category and the safety
category of the welded joint.Note:The weld performance class is
abbreviated by CP (class of performance).
Weld performance classes
CP A (*) - Weld performance class CP A is a special class which
applies only for welds with full penetration and full accessibility
for inspection in production and maintenance
Stress categoriesSafetyHighMediumLowHighCP A (*)CP BCP
C2MediumCP B bCP C2CP C3LowCP C1 dCP C3CP D
Weld inspection class(CT):defines the inspections to be carried
out for a given weld with respect to the weld performance
class.NOTEThe weld inspection class is abbreviated by CT (class of
testing).
Correspondence between weld performance classes and inspection
classes
Stress category:category determined by the stress factorStress
factor: It is ratio of the calculated fatigue stress to the
admissible fatigue stress of the joint type, adjusted by the
appropriate safety factor
Safety categoriesThe safety category defines the consequences of
failure of the single welded joint in respect to the effects on
persons, facilities and the environment. The safety categories are
differentiated as follows:
Low:Failure of the welded joint does not lead to any direct
impairment of the overall function.Consequential events with
personal injuries are unlikely.
Medium: Failure of the welded joint leads to an impairment of
the overall function or can lead to consequential events with
personal injuries.
High:Failure of the welded joint leads to consequential events
with personal injuries and breakdown of the overall function
Relationship between
Stress category. Safety category.Weld performance class.Quality
levels for imperfections.Inspection class and testing.
Given In Next Slide.
Stress categorySafety categoryWeld performance classQuality
levels for imperfections EN ISO 5817Inspection classVolumetric
testsRT or UTSurface testsMT or PTVisual examinationVTHighHighCP
Asee Table 5 orTable 6CT 1100%100 %100 %HighMediumCP BBCT 210%10
%100 %HighLowCP C2CCT 3Not requiredNot required100 %
