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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.