It is important to verify that the pipe materials are impact tested and exhibit a sufficient high Charpy toughness. The low alloy steel pipe of ASTM A333 Gr.6 with a low CDBTT can be used at temperatures down to -45☌. The critical ductile-to-brittle transition temperature (CDBTT) for any steel is the temperature above which the steel behaves in a predominantly ductile manner and below which it behaves in a predominantly brittle manner. Steel is normally considered to be a ductile material, however, it may shatter just as glass at certain low temperatures. Toughness, or ductility, is the ability of a material to resist impact, to withstand repeated reversals of stress, or to absorb energy when stressed beyond the elastic limit. *Tensile requirements for ASTM A333 Gr.6 at room temperature. Mechanical Properties at Room Temperature Manganese, as well as the addition of small traces of nickel, vanadium, copper and niobium, can significantly reduce the critical brittle-ductile transition temperature and refine the grain, therefore, improve the impact toughness. Their amount shall be reduced to the smallest. In terms of the influence on low temperature impact toughness, phosphorus (P) is the most detrimental element among C, Si, P, Si and N to the Charpy toughness of ASTM A333 Gr.6. *For each reduction of 0.01% carbon below 0.30%, an increase of 0.05% manganese above 1.06% would be permitted to maximum of 1.35% manganese. They can also be used for the fabrication of cryogenic equipment as well as refrigeration houses. They may be involved in the scrubber, purification, desulfurization and degreasing processes in oil & gas, petrochemical, coal and pharmaceutical industries. Seamless pipes made from ASTM A333 Gr.6 are primarily used for the construction of pipelines in the production of ethylene, propylene, urea, ammonia, and N-P-K compound fertilizer. They are often connected with flanges of ASTM A350 LF2 and butt-weld pipe fittings of ASTM A420 WPL6. They are usually furnished in nominal pipe size (NPS) and nominal wall thickness with schedule numbers in accordance with ASME B36.10M. The ASTM A333 Grade 6 low alloy steel seamless pipes are intended for low temperature services with minimum design temperature -45☌ requiring notch toughness. The cone-type piercing mill for the production of ASTM A333 Gr.6 seamless pipes, courtesy of BAOSTEEL.
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