Vol.29 SuppL.1 李长荣等：高级管线钢生产适宜洁净度的研究 ·13· high-grade pipeline steel in its production were carried out too.The results show that the linear relationship be- tween the increased steel quality and its improved cleanliness does not exist.The steel cleanliness should not be excessively pursued.It is more beneficial for reducing production cost and enhancing steel quality when the dis- tribution of inclusions is uniform,fine and dispersing when the reasonable steel cleanliness is attained. KEY WORDS linepipe steel:cleanness steel:steel cleanliness;assessmentVol.29 Suppl.1 李长荣等：高级管线钢生产适宜洁净度的研究 • 13 • high-grade pipeline steel in its production were carried out too. The results show that the linear relationship be￾tween the increased steel quality and its improved cleanliness does not exist. The steel cleanliness should not be excessively pursued. It is more beneficial for reducing production cost and enhancing steel quality when the dis￾tribution of inclusions is uniform, fine and dispersing when the reasonable steel cleanliness is attained. KEY WORDS linepipe steel; cleanness steel; steel cleanliness; assessment