Discussion on Sampling Frequency and Acceptance Criteria of Physico-chemical Tests for Steel Tubes

It is identified by the co-authors that in certain prevailing technical speifications for steel pipes for builting natural gas or crude oil pipelines,the requirements for physico-chemical test sampling frenquency are not well standardized,and some acceptance criteria for physico-chemical properties are not so scientifically reasonable.Taking account of relevant requirements under applicable technical specificatons like API Spec 5L(the 44th edition),and the current circumstances of domestic production of steel plate and tubular products,physico-chemical test sampling frequency and some acceptance target value ranges that are more reasonable for the said kind of steel pipes are proposed,aimming at further assurance of steel pipe quality,and scientifically cutting down production costs.