Abstract: A mold set for manufacturing a case is provided. The mold set comprises an upper mold having a fluid channel; a lower mold facing the upper mold; and a drawing mold disposed between the upper mold and the lower mold, wherein the mold set has a case forming space formed among the upper mold, the lower mold and the drawing mold, and the mold set has a sharp-edge forming space communicating with the case forming space, and formed between the drawing mold and the lower mold.

Abstract: A mold set for manufacturing a case is provided. The mold set comprises an upper mold having a fluid channel; a lower mold facing the upper mold; and a drawing mold disposed between the upper mold and the lower mold, wherein the mold set has a case forming space formed among the upper mold, the lower mold and the drawing mold, and the mold set has a sharp-edge forming space communicating with the case forming space, and formed between the drawing mold and the lower mold.

Abstract: A method for forming an U-shaped metal frame includes a preparing means: bend forming a straight tube in a continuous curve shape to be a billet including a spaced section and a first and a second side segments twisted toward opposite directions individually; a forming means: placing the billet into a cavity of a forming mold, closing two ends of the billet, and feeding a high-pressure fluid into the billet; a cutting means: cutting the billet into the first and the second pipes, the first pipe including a first connecting portion formed in a first cut position thereof, the second pipe including a second connecting portion formed in a second cut position thereof; a connecting means: twisting the first side segment and the second side segment toward the same direction, and connecting the first connecting portion and the second connecting portion together to obtain the U-shaped metal frame.