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              Geological drilling pipe

              Geological drilling pipe

              "standard

              YB/T 5052 China Metallurgical Industry Standard

              "use

              For geological drilling

              》Production specifications and materials

              Specifications: 25--356×4--70

              Material: DZ40, DZ50, DZ55, DZ60, DZ65,

              》Steel pipe manufacturing method:

              Hot rolled or cold drawn (rolled)

              "delivery status:

              Pipes with a yield point of less than or equal to 60 kgf/mm2 shall be delivered at normal temperature; pipes with a yield point greater than 60 kgf/mm2 shall be delivered with normalizing and tempering. Hot-rolled steel tubes can be used to control normal finishing temperatures instead of normalizing.