Discussion on Fitting Uniform Elongation into Technical Specification of Steel Linepipe

The requirement for the tensile test as specified under Article 10.2.4 of API Spec 5L—2012 is not strict，while the conversion equation for Oliver elongation rate is not applicable to the high grade steel linepipe. Addressing the problems，here in the essay the advantages as possibly to be brought about by fitting the uniform elongation rate（i.e.，themaximum force general elongation rate）into the technical specification for the steel linepipe are analyzed.As a result，the conclusion ismade as follows.The uniform elongation rate has nothing to do with the shape and size of the specimen.And if the uniform elongation rate is taken as a technical target，and specified under app licable technical specification for the steel linepipe，it is possible to avoid any trouble caused by conversion of the elongation rate as resulting from breaking of tensile test specimenswith different sizes.Therefore it is suggested to fit the uniform elongation rate into applicable technical specification for the steel linepipe.