1. Cylindrical drawing processing: drawing cylindrical products with flanges. Both the flange and the bottom are flat, the cylinder side wall is symmetrical, and the deformation is evenly distributed on the same circumference, and the blank on the flange is deformed by drawing.
2. Elliptical drawing processing: the deformation of the blank on the flange is tensile deformation, but the deformation amount and deformation rate change correspondingly along the contour shape. The greater the curvature, the greater the plastic deformation of the blank; Conversely, the smaller the curvature, the smaller the plastic deformation of the blank.
3. Rectangular drawing processing is used to process low rectangular parts formed by one drawing. During stretching, the tensile resistance at the fillet of flange deformation zone is greater than that at the straight edge, and the deformation degree at the fillet is greater than that at the straight edge.
4. Mountain-shaped drawing process: When the side wall of the stamping part is inclined, the side wall is suspended during the stamping process and will not stick to the die until the end of forming. In the forming process, the deformation characteristics of different parts of the sidewall are not exactly the same.
5. Deep processing of mountain-shaped drawing: The blank deformation of mountain-shaped cover plate is not a simple drawing deformation, but a composite forming in which drawing and bulging deformation coexist. The deformation of the blank on the blank pressing surface is tensile deformation (radial tensile stress and tangential compressive stress), while the deformation of the blank inside the profile (especially in the central area) is bulging deformation (radial and tangential tensile stress).
6. Semi-spherical drawing with flange: When the spherical part is drawn, the blank part is in contact with the spherical top of the punch, and most of the rest is in a free state of suspension without constraint. Therefore, the main technological problem of drawing this kind of spherical parts lies in the serious thinning of local contact parts or the instability and wrinkling of curved surfaces.
7. Flange stretching: shallow stretching the flange part of the stretched product. Its stress and strain are similar to compression flanging. Due to tangential compressive stress, it is easy to wrinkle, so the forming limit is mainly limited by compression wrinkling.
8. Edge-drawing: The flange of the product drawn in the previous procedure is subjected to angular edge-drawing, and the material is required to have good plasticity.
9. Deep drawing: products exceeding the limit of deep drawing need to be stretched for more than two times to complete. Products that have been stretched in the depth direction of the previous station are re-stretched in the depth direction. Wide flange drawing parts are drawn to the required flange diameter in the first drawing, and the flange diameter remains unchanged in subsequent drawings.
10, cone drawing processing: h/d >; For deep conical parts with a depth of 0.8, α =10 ~ 30, the deformation of the blank is large, and the forming force is only transferred from the local area where the blank contacts with the punch, which easily leads to excessive local thinning or even fracture of the blank, and it takes many transitions to gradually form. The step drawing method is to draw the blank into a step transition piece, the step shape of which is tangent to the internal shape of the conical part, and finally expand to form a cone. The stretching times and process of the stepped transition section are the same as those of the stepped cylindrical part.
1 1, rectangular deep drawing: the deformation of high rectangular parts formed by repeated drawing is not only different from that of deep cylindrical parts, but also very different from that of low box parts. Figure 1-46 shows that the shape and size of the product change with the drawing height during multiple drawing when the multi-station automatic conveying press processes a high rectangular box.
12. Curved surface forming: the stretching forming of curved surface makes the outer flange part of the metal blank shrink and the inner flange part extend, and becomes a hollow product with curved surface shape without straight wall and flat bottom.
13. Step drawing processing: the initial drawing product on the left side is drawn again to form the step bottom on the right side. The deep part is deformed at the initial stage of drawing, and the shallow part is deformed at the later stage of drawing. The sidewall of the step change part is easy to induce shear stress deformation.
14. Reverse stretching: reverse stretching the workpiece stretched in the previous process is a re-stretching. The reverse stretching method can increase the radial tensile stress and achieve good anti-wrinkle effect. It can also improve the tensile coefficient of re-stretching.
15. Thinning drawing: Different from ordinary drawing, thinning drawing mainly changes the wall thickness of the drawing part during the drawing process. The gap between the punch and the die is smaller than the thickness of the blank, and the straight wall of the blank is subjected to greater uniform compressive stress when passing through the gap. While the wall thickness becomes thinner in the drawing process, the deviation of the container wall thickness is eliminated, the smoothness of the container surface is increased, and the precision and strength are improved.
16, panel drawing processing: panel products are sheet stamping parts with complex surface shapes. In the process of deep drawing, the deformation of blank is complex, and its forming nature is not simple deep drawing, but compound forming with both deep drawing and bulging.