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3091-2015 implementation of standard certificate (Handan)

3091-2015 implementation of standard certificate (Qian'an)

SGS

Product hygiene license approval No. 1

Product hygiene license approval No. 2

Welded pipe for low pressure fluid delivery - Certificate of

Certificate of qualification

Steel pipe for petroleum and natural gas pipeline system - C

Spiral pipe API certificate

Product standard

Product standard

Special equipment permit