Investigation of the MV Kurdistan casualty

Brittle fracture in structural steels: perspectives at different size-scales

“…The standard test piece has width W, thickness B = W/2, and a crack length a, which has to meet the criterion 0.45 < (a/W) < 0.55. For 'validity', all dimensions are incorporated in the limit set on B: B > 2.5(K 1c /σ Y ) 2 . Taking as an example nuclear reactor pressure vessel (RPV) steel, of yield strength, 400 MPa and fracture toughness 200 MPa m 0.5 , B is calculated as 625 mm.…”

“…If the crack length increases, owing to subcritical crack growth, both K r and L r increase, because K app increases and L GY decreases: the assessment point moves closer to the failure locus. A worked example of how a critical defect size can be deduced by carrying out a series of assessments for different postulated defect sizes (for a defect in the stress field of a large nozzle) is given in reference [7], and an example of the use of an FAD analysis based on CTOD data is to be found in reference [2], describing the failure analysis of MV Kurdistan. In service, a number of possible changes in material properties may occur and affect the position of P. At high temperature, material could become softened, increasing L r .…”

“…The King's Bridge in Melbourne, Australia suffered a brittle fracture in 1962. Brittle failures in ships continue: three such are the World Concord in 1954, MV Kurdistan in 1979 [2] and the Selendang Ayu in 2004. Brittle fractures have also occurred in boilers and pressure vessels, even in the 'proof test' when 20% over-pressure is applied before the vessel enters service.…”

Interacting Cracks Analysis Using Finite Element Method

“…Crack interaction that induced from MRSP has caused many catastrophic failures , for example in aircraft fuselage (Hu, Liu, & Barter, 2009), F-18 Hornet bulkhead (Andersson et al, 2009), rotor fault (Sekhtar, 2008), gigantic storage tanks (Chang & Lin, 2006), oil tankers (Garwood, 2001), polypropylene tank ) and the most recent is the fail of helicopter longerons (J. A.…”

“…Brittle failure of Oil Tanker structures at welded joints (Garwood, 2001) Array of edge cracks Failure of heat-checked gun tubes and rapidly cooled pressure vessels (Parker, 1999) Semi-elliptical surface cracks…”