Metallic tubular products with enhanced collapse resistance
AssigneeUnited States Steel Corporation
InventorsPeter W. Moore, Bisen Lin
Life of this patent
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Abstract
Metallic tubular products having improved collapse resistance are disclosed. The metallic tubular products are produced by compressive forming processes. The method comprises identifying the types of stress that can be applied in order to change the residual stress profile of metallic tubular products, such as those that have completed a straightening process, and results in a residual stress profile that improves collapse resistance. The metallic tubular products are subjected to radial compression processing to control the residual stress profile and to enhance collapse resistance. The radial compression process may be used after the tubular product has been subjected to a straightening process.
Claims14
A radially compressed metallic hollow tubular product comprising an outer diameter and an inner diameter, wherein the radially compressed metallic hollow tubular product has a compressive residual hoop stress adjacent to an inner surface thereof, and a tensile residual hoop stress adjacent to an outer surface thereof, and wherein the radially compressed metallic hollow tubular product has a collapse resistance that is at least 2 percent greater than a collapse resistance of the metallic hollow tubular product prior to radial compression, and has:
- (a) a substantially reduced compressive residual hoop stress adjacent to an inner surface thereof, or
- (b) a tensile residual hoop stress adjacent to the inner surface thereof,
- the radially compressed metallic hollow tubular product has:
- (a) a substantially reduced tensile residual hoop stress adjacent to an outer surface thereof;
- or
- (b) a compressive residual hoop stress adjacent to the outer surface thereof;
- and
- wherein the radially compressed metallic hollow tubular product has a residual hoop stress adjacent to the inner surface of from −10 to +30 percent of a yield strength of the radially compressed metallic hollow tubular product.
A radially compressed metallic hollow tubular product comprising an outer diameter and an inner diameter, wherein the radially compressed metallic hollow tubular product has a compressive residual hoop stress adjacent to an inner surface thereof, and a tensile residual hoop stress adjacent to an outer surface thereof, and wherein the radially compressed metallic hollow tubular product has a residual hoop stress adjacent to the inner surface of from −10 to +30 percent of a yield strength of the radially compressed metallic hollow tubular product, and has:
- (a) a substantially reduced compressive residual hoop stress adjacent to an inner surface thereof, or
- (b) a tensile residual hoop stress adjacent to the inner surface thereof, and
- the radially compressed metallic hollow tubular product has:
- (a) a substantially reduced tensile residual hoop stress adjacent to an outer surface thereof;
- or
- (b) a compressive residual hoop stress adjacent to the outer surface thereof.
Dependencies are inferred from the claim text.