Method for manufacturing an air-gap-insulated exhaust manifold

US6038769A · kind A · utility

Assignee

• Daimlerchrysler AG · US

Inventors

• Pierre Bonny · Hamburg, DE
• Norbert Kreutzig · Hamburg, DE
• Thorsten Sternal · Moisburg, DE

Key dates

• Filing date: Feb 19, 1998
• Grant date: Mar 21, 2000
• Expiry date: Feb 19, 2018

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T29/49398
• WIPO field: Environmental technology
• WIPO sector: Chemistry

Abstract

A method for manufacturing an air-gap-insulated exhaust manifold, including exhaust-conducting inner tube sections and an outer shell divided into an upper shell and a lower shell, with the inner tube sections, of which at least one is designed as a curved tube, being plugged into one another. The inner tube sections plugged into one another are inserted as an assembled component into the lower shell, centered relative to the outer shell that is formed later, with the upper shell then being placed on the lower shell and pressed against the latter. Then the upper and lower shells and the inner tube sections are welded to the outer shell at those points at which they pass through the outer shell. In order in simple fashion always to ensure a sliding fit on the inner tube sections as well as the formation of a uniform air gap insulation of the inner tube sections following completion of the manufacture of the exhaust manifold, it is proposed to connect the inner tube sections with each other forcewise before they are inserted into the lower shell by means of a connecting element in each case made of a heat-volatile material, with the connecting elements being dissolved under the influ…