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:
Apr. 24, 2001
Filed:
Sep. 28, 1999
Wilheim Nickel, Mülheim, DE;
Theodor Schmitz, Grevenbroich, DE;
Wilfried Schmidt, Erkrath, DE;
Hans-Jürgen Schlüssel, Dormagen, DE;
Mannesmann AG, Düsseldorf, DE;
Abstract
A process for producing a cylinder having at least one longitudinally extending outward bulge and a steel base, for a piston-cylinder unit. The process including the steps of initially machining a round input ingot to size, the ingot having a length, subsequently heating the ingot to a deformation temperature between 1250° C. and 1310° C., descaling an entire surface of the heated ingot with pressurized water, subsequently inserting the ingot into a mold, piercing the ingot in a sharply increasing manner using a mandrel so as to form a pierced piece with a base, applying a lubricant to the mold and the mandrel prior to piercing, subsequently ejecting the pierced piece from the mold, cooling and descaling the ejected pierced piece, and mechanically finish-machining the pierced piece to produce the cylinder.