16 types of metal stamping and stretching processing using stamping equipment:

01. Cylinder stretching processing

Stretching of flanged cylindrical products. The flange and bottom are both flat in shape, and the cylindrical side wall is axisymmetric. The deformation is evenly distributed on the same circumference, and the blank on the flange undergoes deep drawing deformation.

02. Elliptical stretching processing

The deformation of the blank on the flange is tensile deformation, but the deformation amount and deformation ratio change correspondingly along the contour shape. The larger the curvature of the local area, the greater the plastic deformation of the blank; On the contrary, the smaller the curvature of the local area, the smaller the plastic deformation of the blank.

03. Rectangular stretching processing

A low rectangular component formed by one-time stretching. When stretching, the tensile resistance at the rounded corners of the flange deformation zone is greater than that at the straight edges, and the deformation level at the rounded corners is greater than that at the straight edges.

04. Yamagata stretching processing

When the side wall of the stamped part is inclined, the side wall is suspended during the stamping process and does not adhere to the mold until it is formed. The deformation characteristics of different parts of the sidewall during forming are incomplete and identical.

05. Hill shaped stretching processing

The blank deformation of the dome shaped cover plate during the forming process is not simply tensile deformation, but a composite forming process where tensile and bulging deformation coexist. The deformation of the blank on the pressing surface is tensile deformation (radial is tensile stress, tangential is compressive stress), while the deformation of the blank inside the contour (especially in the central area) is bulging deformation (both radial and tangential are tensile stress).

06. Semi spherical stretching processing with flange

When the spherical part is stretched, the top part of the spherical part of the blank and the convex mold come into contact, while the other large parts are in a free and unconstrained state of suspension. Therefore, the main process problem of stretching such spherical parts lies in severe thinning of the contact area or instability and wrinkling of the curved surface.

07. Flange stretching processing

Stop the shallow stretching process on the flange of the stretched product locally. Its stress-strain condition is similar to that of a tight flange. Due to tangential compressive stress, it is prone to wrinkling, so forming is mainly limited by compression wrinkling.

08. Edge stretching processing

Stop the angular stretching process on the flange part of the stretched product in the previous process, and this processing request has good plasticity.

09. Deep stretching processing

Stretching products that go beyond stretching processing require two or more repeated stretches to be completed. Products that have undergone stretching processing in the depth direction at the front workstation are stopped for further stretching processing in the depth direction. The wide flange stretching part is stretched to the required flange diameter during the first stretching, and the flange diameter remains unchanged during subsequent stretching.

10. Cone stretching processing

For deep conical parts with h/d>0.8 and α=10 °~30 °, due to their large depth, the deformation level of the billet is relatively high. Relying solely on the contact area between the billet and the punch to transmit forming force can easily cause the billet to become excessively thin and break, requiring multiple transitions to gradually form. The step stretching method is to first stretch the billet into a step shaped transition piece, whose step shape is tangent to the inner shape of the conical part, and finally form a conical shape. The stretching frequency and process of the stepped transition piece are the same as those of the stepped cylindrical piece.

11. Rectangular stretch processing

The deformation of high rectangular parts formed by repeated stretching is not only different from that of deep cylindrical parts, but also significantly different from that of low box shaped parts. The picture shows the changes in the shape and size of the workpiece with the stretching height during the repeated stretching process when the multi station automatic conveying press stops processing high rectangular box parts.

12. Surface Forming Processing

Curved surface stretching forming is a stamping method for hollow products with non straight walls and non flat bottoms, which reduces the outer flange of the metal flat billet locally and elongates the inner flange locally.

13. Step stretching processing

Stop the initial stretching process on the left side and shape it into a stepped bottom on the right side. Deeper areas undergo deformation in the early stages of stretching, while shallower areas undergo deformation in the later stages of stretching. The local sidewall changes in the steps can easily induce shear stress and deformation.

14. Reverse stretching processing

Stopping reverse stretching of workpieces processed by stretching in the previous process is a form of re stretching. The reverse stretching method can increase radial tensile stress and achieve good results in avoiding wrinkling. It is also possible to improve the stretching coefficient of re stretching.

15. Thinning and stretching processing

Unlike regular stretching, thinning stretching mainly involves changing the thickness of the stretching tube wall during the stretching process. The gap between the convex and concave molds is smaller than the thickness of the blank. When the straight wall of the blank passes through the gap, it is under a larger average compressive stress. During the stretching process, the wall thickness becomes thinner while eliminating the deviation of the container wall thickness, increasing the lubrication of the container surface, and improving accuracy and strength.

16. Panel stretching processing

Panel products are sheet metal stamping parts with complex appearances. In the stretching process, the deformation of the blank is complex, and its forming properties are no longer simple stretching forming, but a composite forming that involves both deep drawing and bulging.