Patent ID: 6153029
Filing Date: 2000-11-28
Classification: B21C,Y10T

Abstract:
A method for the production of a tapered bent tube, involving:(a) a U-cup with a full opening, that is punched to form from a brass plate in a primary mold, the two ends of said full opening of said U-cup being of different calibers;(b) said U-cup is then subjected to tempering treatment to eliminate its processing stress;(c) said full opening of the U-cup is punched by an assembly forming mold to form a rough shape of tapered bent tube with two ends of different calibers, and between said two different calibers is a flattened part;(d) said flattened part on said rough shape of the tapered bent tube is punched out to form a tapered bent tube; and(e) the seam of said tapered bent tube is welded and smoothed by rollers.