Sheet metal fabrication process is called sheet metal processing. Specifically, for example, the use of plates to make chimneys, iron barrels, oil tanks, oil pots, ventilation pipes, large and small ends of elbows, round places, funnel shapes, etc. the main processes include shearing, bending and edge buckle, bending forming, welding, riveting, etc., which requires certain geometric knowledge. Sheet metal parts are sheet metal parts, that is, parts that can be processed by stamping, bending, stretching and other means. A general definition is parts with constant thickness in the processing process. Corresponding to casting parts, forging parts, machined parts, etc.