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:
Nov. 20, 1984
Filed:
Sep. 28, 1982
Applicant:
Inventors:
Gerald R Trudell, Pinconning, MI (US);
Theodore F Kraska, Pinconning, MI (US);
Dennis W Barber, Kawkawlin, MI (US);
Assignee:
APX Group, Inc., Toledo, OH (US);
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B23P / ; B23P / ;
U.S. Cl.
CPC ...
29523 ; 29525 ;
Abstract
Double walled tubing, a method and apparatus for producing the same are disclosed. First and second metal tubes of substantially identical diameters are selected. One end of the second tube is expanded, and the first tube is pushed into the second tube. By mounting the first tube on a mandrel having a mandrel ball with an outer diameter which approximates the inner diameter of the first tube, any creases in the first tube caused by the insertion will be removed by the mandrel ball upon withdrawing the mandrel from the first tube.