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. 09, 1988
Filed:
Oct. 01, 1986
George K Snyder, Lockport, NY (US);
General Motors Corporation, Detroit, MI (US);
Abstract
Method and apparatus therefor for forming an inner tube and turbulator for a concentric tube heat exchanger from a stock length of tube comprising the steps of simultaneously mechanically forming a bell-shaped sealing and outer tube attaching section in the ends of the tube while also sealing the ends, applying hydraulic pressure to the interior of the tube to form outwardly projecting turbulator bumps in the tube at places located about and along the length thereof, and increasing the mechanical forming force with increasing hydraforming force so that the latter opposes the former and only their net force acts on the bell-shaped sections to maintain the sealing during the hydraforming to prevent coining of these sections.