Non-magnetic Large-diameter Rod

I. Commonly used materials

1. 0Cr13Mn18Ni2MoN (SMF166): It belongs to low-carbon alloy steel and has good low magnetic permeability, hardness, toughness, and corrosion resistance. It is commonly used in the manufacture of non-magnetic drill collars.

2. 15-15HS Max: It is a high nitrogen strengthened austenitic stainless steel, containing elements such as 16% -19% manganese, 18% -21% chromium, and 3% nickel, with excellent resistance to intergranular corrosion and pitting corrosion.

3. P550 non-magnetic steel: It is a high manganese, high chromium, and high nitrogen nickel non-magnetic steel with a carbon content of ≤ 0.06%, manganese content of 20.5% -21.6%, nickel content of ≥ 1.4%, and chromium content of 18.3% -20.0%. It has the characteristics of high strength and stable structure.

II. Performance characteristics

1. High precision and smoothness: The non-magnetic large-diameter rod has high dimensional accuracy and low surface roughness, with a general roughness of Ra0.8-Ra1.6 μ m. This helps reduce subsequent processing steps, improve the machining accuracy and surface quality of the parts.

2. Good comprehensive mechanical properties: It has high strength, high toughness, and wear resistance, and can withstand various complex loads during oil drilling. The tensile strength of 0Cr13Mn18Ni2MoN (SMF166) is ≥ 827MPa, and the yield strength is ≥ 758MPa.

3. Excellent non-magnetic performance: The non-magnetic large-diameter rod has extremely low magnetic permeability, which can avoid interference with magnetic measuring instruments and ensure the accuracy of drilling parameter measurement.

III. Processing technology

Usually, large-diameter billets are first produced by hot rolling or forging, and then subjected to precision rolling, cold drawing, or turning processes to improve dimensional accuracy and surface smoothness. In order to obtain good performance, heat treatment such as solution treatment and aging treatment may also be required.

IV. Application areas

Non magnetic large-diameter rods are mainly used to manufacture large non-magnetic drill collars, large sheaths for measurement while drilling (MWD) or logging while drilling (LWD) instruments, large rotary directional drilling tools and other petroleum machinery components. These components play a crucial role in oil drilling, and the characteristics of non-magnetic large-diameter rods help improve the efficiency and safety of oil drilling.