Forming device and method for large thin-walled part with curved surface

A forming device for a large thin-walled part with a curved surface, comprising a punch, a blank holder, a die, a lower die plate, a first annular sleeve and second annular sleeves, wherein the punch and the blank holder can be connected with a press, and the press can drive the punch and the blank holder to move up and down;

• the blank holder is arranged at a top of the die, the lower die plate is arranged at a bottom of the die, and the first annular sleeve is arranged in a cavity of the die;
• the first annular sleeve is connected with first driving oil cylinders, and the first driving oil cylinders can drive the first annular sleeve to move up and down;
• an inner diameter of the die is greater than an outer diameter of the punch;
• the first annular sleeve is wholly arranged in a gap between a first side of the punch and a first side of the die, the first side extends in an axial direction of the punch, and the first side of the die side is a wall of the cavity of the die and extends in a height direction of the die;
• the second annular sleeves are arranged below the punch;
• the first annular sleeve is arranged outside the second annular sleeves;
• each of the second annular sleeve is connected with second driving oil cylinders, and the second driving oil cylinders can drive the second annular sleeves to move up and down;
• the first driving oil cylinders and the second driving oil cylinders are connected with a hydraulic system;
• one surface of the first annular sleeve and one surface of each of the second annular sleeves towards the punch are arc-shaped;
• wherein the large thin-walled part with a curved surface has a diameter of more than 3000 mm and a thickness of 10 mm;
• and
• wherein the second annular sleeves comprise three second annular sleeves, and the three second annular sleeves have a common axis and have different radii.