Joining two coaxial tubes in a cylinder barrel casing of a combustion engine of an automobile, comprises welding the tubes when inserted one into the other, and deforming outer wall of outer tube during the welding

摘要

The method for joining two coaxial tubes including an internal tube (1) made of cast iron and an outer tube (2) based on aluminum or its alloy, comprises welding the tubes when inserted one into the other, where an outer wall of the inner tube has a given initial profile prior to fastening, and deforming an outer wall of the outer tube during the welding according to the shape of the given initial profile. The outer tube has an average thickness of 0.5-2 mm. The initial profile of the outer wall has recessed patterns in the form of grooves of continuous or discontinuous indentations. The method for joining two coaxial tubes including an internal tube (1) made of cast iron and an outer tube (2) based on aluminum or its alloy, comprises welding the tubes when inserted one into the other, where an outer wall of the inner tube has a given initial profile prior to fastening, and deforming an outer wall of the outer tube during the welding according to the shape of the given initial profile. The outer tube has an average thickness of 0.5-2 mm. The internal tube has an average thickness of 6-10 mm. The initial profile of the outer wall of the internal tube has recessed patterns in the form of grooves of continuous or discontinuous indentations. The grooves have depth of 0.2-2 mm. The initial profile of the outer wall is obtained during the manufacturing of the internal tube by shell molding and after the manufacturing the internal tube by threading or mechanical machining. The outer wall of the outer tube is deformed during the welding according to the initial profile given to present a profile of similar shape and equal or lesser average depth. Independent claims are included for: (1) a cylinder barrel casing; and (2) a method of casting a cylinder barrel casing.