China 'GB/T 29047-2021
' standard english version:
NATIONAL STANDARD OF THE PEOPLE'S REPUBLIC OF CHINA
GB/T 29047-2021
Prefabricated directly buried insulating pipes and fittings with polyurethane foamed-plastics and high density polyethylene casing pipes 高密度聚乙烯外护管硬质聚氨酯泡沫塑料预制直埋保温管及管件
Issued Date:2021/8/20
Implemented Date:2022/3/1
Issued by:
The Standardization Administration of the People's Republic of China