Special Seamless steel pipe factory for ship ,project ,machine part and so on .Materials and standard is API 5L Gr.B /ASTM A106 Gr.B /ASTM A53 Gr.B/ GOST8732 CT20 Special Seamless steel pipe factory
for ship ,project ,machine part and so on .Materials and standard is API 5L Gr.B /ASTM A106 Gr.B /ASTM A53 Gr.B/ GOST8732 CT20