forging and forming technology: Design Points of Bending Molding
The forging and forming technology of bending molding is mainly used to process complex shapes with large deformation. In metal forming processing technology, the technology of bending molding has been widely used, and it is an indispensable technology in processing.
This paper is mainly to explain the design points of bent die, including the initial design points, traditional design points and modern design points.
I. Initial Design Point
The initial design point of the bending die is the design of the flow path and the draft angle of the die surface.
1. Flow path design
When designing the flow path of the bending die, the designer should pay attention to the following two points:
(1) The die should be designed with a complete flow path, which is conducive to the forming of the forging blank.
(2) The shape of the forging blank and the shape of the flow path should be symmetrical, so as to ensure the uniform distribution of the plastic flow force in the forging process.
2. Design of the draft angle
When designing the draft angle of the die surface, the designer should pay attention to the following points:
(1) According to the shape of the bending die, the height of the draft angle should be determined, so as to ensure the smooth forming of the pieces in the die.
(2) The height and angle of the draft angle should be determined according to the size of the material being formed. Generally, the smaller the material, the larger the draft angle and the height of the draft angle should be.
(3) The draft angle of each die should be designed in the same direction, so that the pieces can be formed smoothly during the forming process.
II. Traditional Design Point
The traditional bending die design mainly includes the material selection, die structure, thickness design and other content.
1. Material selection
The material of the traditional bending die is mostly made of 40Cr and 55Cr for its excellent wear resistance, impact resistance and plastic properties. Three parts of the die: core shaft, sleeve and die head should be selected from high strength structural steel. The other parts of the bending die are made of cast iron.
2. Die structure
The structure of the traditional bending die is mainly composed of the following parts: die head, core center, sleeve and other parts. The die head is mainly used to fix the parts, and the sleeve is mainly used to fix the core center. The core center is the part that supports the internal structure of the die, and the die surface is formed on the core center.
3. Thickness design
The thickness of the traditional bending die is generally determined according to the forming technology and material. Generally, the thickness of the bending die should be greater than that of the workpiece. According to the forming materials, if it is an ordinary material, the thickness of the bending die should be 1.5 times that of the workpiece; if it is a super plastic material, the thickness of the bending die should be 2 times that of the workpiece.
III. Modern Design Point
The modern design of the bending die includes the selection of materials, the use of die structure and modern manufacturing methods.
1. Material selection
The materials of modern bending dies are mostly made of alloy tool steel or hard alloy steel, which have excellent performance in wear resistance and strength. The core shaft, sleeve and die head of the modern bending die are all made of tool steel with high hardness and strength.
2. Die design
The modern die structure designed with computer simulation, the structure is more reasonable, for the different materials to design different supporting structure size and shape, so that the bending parts of the forming process is more scientific and reasonable, more conducive to the processing of parts.
3. Manufacturing method
The modern manufacturing method of the bending die is the composite machining method, which combines the advantages of machining, forging, casting and other processes. It is a kind of manufacturing method which combines these processes in a reasonable way and has the advantages of high accuracy, good service life and rich variety of structures.
IV. Conclusion
Bending molding technology is a kind of important processing technology in metal forming, and its design is also very important. This paper mainly introduces the design points of the bending die, including the initial design point, traditional design point and modern design point.
The initial design of the bending die should pay attention to the flow path design and draft angle design. The material selection, die structure and thickness design should be considered in the design of the traditional bending die. The modern design point of the bending die includes the selection of materials, the use of die structure and modern manufacturing methods. Through reasonable design, the quality of the parts can be guaranteed, and the safety of the personnel and the processing efficiency of the parts can be avoided.
