Special applications of steel pipes for hydraulic cylinders require high strength and good toughness. Cold drawn and stress-relieved tubes are commonly produced with tolerances suitable for subsequent machining processes such as honing or skiving and burnishing. Traditional manufacturing cycles offer materials with high-tensile properties but do not guarantee good transversal toughness at low temperatures. This could cause problems in case of hydraulic cylinders operating in external adverse conditions. In this context, Tenaris has developed a new product with both high toughness and high strength. This paper presents the main issues in the devel opment of this material, which guarantees yield greater than 690 MPa and impact toughness in the transverse direction higher than 27 J, at temperatures at least down to -40℃. The paper ends with an experimental analysis of the effects of this improvement on the burst behavior at low temperature.
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