天津钢管集团股份有限公司,天津大无缝钢管集团,J55,K55,N80Q,37mn5,36mn2v油井管
天津钢管集团股份有限公司,天津大无缝钢管集团,J55,K55,N80Q,37mn5,36mn2v油井管,N80Q石油专用管,p110石油套管,30crmo,35crmo,4140,cfs11,20cr,40cr,s355j2h,s275jr,E355,45mn2,27simn,gcr15精密钢管,P235GH,P265GH,00cr19ni10,2520,304L,sus316L,