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Pressurized piping items in power plants may experience combined torsion andbending moments during operation. Currently, there is a lack of guidance in flaw evaluationprocedures for combined loading modes of pressure, torsion and bending loads. Recently,collapse bending moments for pipes under torsion moments were analysed by finite elementmodelling. Equivalent moments defined as the root of the sum of the squares of the torsion andbending moments are shown to be equal to pure bending moments for various diameter pipescontaining circumferentially part-through cracks. This paper focuses on behaviour of plasticcollapse moments for pipes with circumferential through-wall cracks using finite elementanalysis, and describes the behaviour of the equivalent bending moments for flaw evaluationprocedures, referring part through cracked pipes.