The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 01, 2017
Filed:
Jun. 26, 2008
Markus Ring, Haan-Gruiten, DE;
Gerd Kloster, Mülheim/a.d. Ruhr, DE;
Oliver Sommerkamp, Essen, DE;
Caroline Rott, Düsseldorf, DE;
Marion Erdelen-peppler, Willich, DE;
Markus Ring, Haan-Gruiten, DE;
Gerd Kloster, Mülheim/a.d. Ruhr, DE;
Oliver Sommerkamp, Essen, DE;
Caroline Rott, Düsseldorf, DE;
Marion Erdelen-Peppler, Willich, DE;
VALLOUREC DEUTSCHLAND GMBH, Düsseldorf, DE;
Abstract
The invention relates to a method for the production of hot-finished, particularly hot-rolled, seamless pipes having optimized fatigue properties in the welded state, having an outside diameter of up to 711 mm and a nominal wall thickness of up to 100 mm, made of metal, in particular steel. After hot or finish rolling, a defined pipe cross-section is produced on at least one pipe end across a predetermined length, having tight tolerances for inside and outside diameters, wherein the cross-section can then be welded to the pipe end of another pipe. According to the invention, in a region a wall thickness is created in a first step at the pipe end in question, the thickness being bigger than on the remaining pipe body, wherein the outside diameter is increased and/or the inside diameter is reduced. In a second step, the required pipe cross-section is produced in said region by mechanical treatment, and the transition from the treated to the untreated region of the pipe is produced with low surface roughness and almost notch-free, and the residual wall thickness remaining in the treatment region is within the required tolerances.