At present, stamping elbows are basically thick-walled or alloy materials, and elbows with ordinary wall thickness are basically made by pushing, but the appearance of stamping elbows is not very beautiful, and they are easy to be crushed or bumped, and a lot of shaping processes are needed.

Caliber forming is, after all, a stamping production process. No matter how precise the fixture is, the caliber will not be as accurate as pushing the elbow. Stamping elbows are basically oval as soon as they are stamped, and generally need straps and bayonets. In the case of large wall thickness, the caliber is basically pressed to the national standard caliber first, and then the ball is processed. After all, bayonets are more difficult than braces.

Stamping forming, after the punching elbow is finished, the two ends of the punching elbow are warped due to stress, and it needs to be punched twice, that is, after the punching-bending ratio, it needs to be punched again, that is, warping. Make it reach the size required by national standards.

Wall reduction treatment, punching elbow is generally thick-walled or alloy, and the thickness of blank is generally about the thickness of orderly punching elbow. Wall reduction is generally the inner wall reduction, so that the offset is less than 3 mm.