CN109201830B - A method of preventing flange defect occur without bottomless drum shape part spinning process - Google Patents

Abstract

The invention provides a method for preventing flanging defects in the spinning process of the cylindrical part. During the process of spinning the blank of the cylindrical part, a part of the blank is reserved at the mouth of the cylindrical part and does not participate in the deformation. Aiming at the problem that flanging defects are prone to occur at the mouth of the part during the spinning process of the cylindrical part, the invention proposes a method in which a small amount of the blank of the cylindrical part at the mouth does not participate in the deformation, so that the area participating in the spinning deformation is affected by both sides. Axial restraint to avoid flanging defects.

Description

A method for preventing flanging defects in the spinning process of cylindrical parts without bottoms

technical field

The invention relates to the technical field of metal plastic forming, in particular to a method for preventing flanging defects from occurring during the spinning process of a cylindrical part without a bottom.

Background technique

Spinning is a metal plastic forming method for forming thin-walled hollow rotary parts. It is formed by applying pressure to the rotating blank with the help of a rotary wheel and other tools to produce continuous local plastic deformation. Usually, the metal flat blank or prefabricated blank is clamped on the mandrel of the spinning machine, and the mandrel and blank are rotated by the spindle, and then the rotary wheel applies pressure to the blank at a certain trajectory and moving speed, so that the blank produces continuous, Point-by-point plastic deformation to obtain hollow rotating body parts with various busbar shapes. Among them, strong spinning is a forming method that not only changes the shape and size of the blank, but also significantly reduces its wall thickness during the forming process. Power spinning is often used for shear spinning of sheet blanks, forward spinning of cylindrical blanks with a bottom, and flow spinning of cylindrical blanks without a bottom.

In order to obtain high-performance large-scale thin-walled cylinder parts, reverse spinning technology is used instead of coil welding process. As shown in Figure 1, for cylindrical parts without bottom, reverse spinning can be used to complete the high-precision machining of the cylinder. Not limited by the length of the mold, the cylinder can be rotated with the main shaft by the simple method of using the unloading ring, so the cylinder without bottom usually adopts the reverse spinning method. During the reverse spinning process, since the material at the mouth of the part is only constrained by the undeformed area, the other end lacks restraint, which makes the mouth easy to flaring and flanging. As the spinning continues, the subsequent blanks are subject to the simultaneous constraints of the undeformed area and the deformed area, and the forming process is stable and controllable.

Flanging is an inevitable problem in the spinning process of thin-walled cylindrical parts. Flanging causes the size of the mouth of the part to be out of tolerance. Usually, enough machining allowance is left to cut off the out-of-tolerance part, and flanging is a process of instability. , the influence of each part flanging on the dimensional accuracy is inconsistent, so it is necessary to increase the size of the machining allowance, which reduces the material utilization rate of spinning.

After multiple passes of spinning, the material is repeatedly rolled under the condition of lack of constraints, resulting in serious flanging or even flanging, which affects the subsequent spinning forming. It is necessary to remove the flanging part before continuing spinning. Reduced forming efficiency. For materials with poor plasticity, the appearance of flanging defects is easy to cause cracks in the mouth, resulting in the scrap of the part.

SUMMARY OF THE INVENTION

Aiming at the problem that flanging defects are prone to occur at the mouth of the part during the spinning process of the cylindrical part without a bottom, the present invention proposes a method for preventing flanging defects from occurring in the spinning process of the cylindrical part without a bottom. A small amount of blanks do not participate in the deformation, so that the area participating in the spinning deformation is subject to the axial restraint force on both sides to avoid flanging defects.

The invention provides a method for preventing flanging defects in the process of spinning a cylindrical piece without a bottom. A part of the blank is reserved not to participate in the deformation.

Further, a reinforcing rib is arranged on the part of the blank where the mouth of the cylindrical member without bottom does not participate in the deformation.

Further, during reverse spinning forming, the specific steps are: adjusting the position of the rotary wheel, so that the radial position of the rotary wheel is greater than the maximum radius of the blank; Move a set distance; start the main shaft, the blank rotates circumferentially with the main shaft, the rotary wheel feeds radially to the set pressure feed amount; the rotary wheel performs axial feed for spinning forming.

Further, in the process of multi-pass spinning, starting from the middle pass, a part of the blank is reserved at the mouth of the cylindrical piece without the bottom and does not participate in the deformation.

Aiming at the problem that flanging defects are prone to occur at the mouth of the part during the spinning process of a cylindrical part without a bottom, the invention proposes a method in which a small amount of blanks at the mouth do not participate in the deformation, so that the area participating in the spinning deformation is affected by the shafts on both sides. to the binding force to avoid flanging defects.

Additional aspects and advantages of the present invention will be set forth, in part, from the following description, and in part will be apparent from the following description, or may be learned by practice of the invention.

Description of drawings

1 is a schematic diagram of the equipment and processing state of the prior art of the present invention;

2 is a schematic diagram of the equipment state of step S10 of a method for preventing flanging defects in a spinning process of a cylindrical part according to an embodiment of the present invention;

3 is a schematic diagram of the equipment state of step S20 of a method for preventing flanging defects in a spinning process of a cylindrical part according to an embodiment of the present invention;

4 is a schematic diagram of the equipment state of step S30 of a method for preventing flanging defects in a spinning process of a cylindrical part according to an embodiment of the present invention;

5 is a schematic diagram of the equipment state of step S40 of a method for preventing flanging defects in a spinning process of a cylindrical part according to an embodiment of the present invention;

6 is a schematic structural diagram of a blank with reinforcing ribs according to an embodiment of the present invention;

7 is a schematic diagram of the equipment state of another method for preventing flanging defects during the spinning process of a cylindrical part according to an embodiment of the present invention;

FIG. 8 is a flow chart of a method for preventing flanging defects during the spinning process of a cylindrical part according to an embodiment of the present invention.

Detailed ways

The following describes in detail the embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary, and are intended to explain the present invention and should not be construed as limiting the present invention.

The invention provides a method for preventing flanging defects in the process of spinning a cylindrical piece without a bottom. A part of the blank is reserved not to participate in the deformation. During reverse spinning, as shown in Figure 8, the specific steps are:

In step S10, the position of the rotary wheel is adjusted so that the rotary wheel is placed outside the maximum radius of the blank. At this time, the schematic diagram of the equipment state is shown in FIG. 2 .

In step S20, the rotary wheel performs axial feeding, and moves forward a set distance from the processing starting end of the blank. At this time, the schematic diagram of the equipment state is shown in FIG. 3 . Since the thickness of the blank is thinner, the flanging defect is more likely to occur. At the same time, as the diameter of the blank increases, the self-binding force of the blank becomes worse. The implementation of this patent can refer to Table 1 to set the distance that the rotary wheel moves forward from the starting end. When the diameter of the blank is small and the wall thickness is large, the downward movement of the rotary wheel can be reduced or even cancelled. Table 1 shows the corresponding relationship between the value of the forward movement distance of the rotary wheel from the starting end and the diameter of the blank and the wall thickness of the blank.

Table 1 The value of the distance that the rotary wheel moves forward from the starting end Unit: mm

Note: "/" in the table means that the rotary wheel does not need to move forward.

In step S30, the blank rotates circumferentially with the main shaft, and the rotary wheel is fed radially to the set pressing feed amount. At this time, the schematic diagram of the equipment state is shown in FIG. 4 .

In step S40, the rotary wheel is fed axially, and spinning is performed. At this time, the schematic diagram of the equipment state is shown in FIG. 5 .

In one aspect of the embodiment of the present invention, as shown in FIG. 6 , a reinforcing rib is provided on the part of the blank where the mouth of the cylindrical member without bottom does not participate in the deformation. During the billet making process, a reinforcing rib is reserved at the open end of the billet. The thickness of the reinforcing rib can refer to Table 1. The outer diameter of the reinforcing rib can be the maximum diameter after rough machining of the ring-rolled billet. The arrangement of the reinforcing ribs can further prevent the occurrence of flanging during the processing of the cylindrical part without the bottom. The invention is suitable for preventing the occurrence of flanging during the spinning forming process of single-rotation wheel, double-rotation wheel, triple-rotation wheel and multi-rotation wheel. to reduce the thickness of the reinforcing ribs.

In one aspect of the embodiment of the present invention, in the process of multi-pass spinning, starting from the middle pass, a portion of the blank is reserved at the mouth of the cylindrical member without the bottom and does not participate in the deformation. Especially in the multi-pass spinning forming process with thick billet wall thickness, the rotary wheel can not move forward or the moving distance can be reduced during the first few passes, which is beneficial to improve the utilization of materials. Rate.

As shown in Fig. 7, the present invention can also be applied to the forward spinning process of cylindrical parts, and the spinning as shown in Fig. 7(a) and Fig. 7(b) are completed as in the conventional forward spinning process. The stable spinning shown; in the final spinning of the forward spinning, instead of forming all the blanks of the cylinder section, some blanks are reserved at the mouth of the cylinder so as not to participate in the deformation, as shown in Figure 7(c). to prevent the blank from flanging.

Aiming at the problem that flanging defects are prone to occur at the mouth of the part during the spinning process of the cylindrical part, the invention proposes a method in which a small amount of blanks at the mouth do not participate in the deformation, so that the area participating in the spinning deformation is subject to the axial restraint force on both sides , to avoid flanging defects.

Although the embodiments of the present invention have been shown and described above, it should be understood that the above-mentioned embodiments are exemplary and should not be construed as limiting the present invention. Embodiments are subject to variations, modifications, substitutions and variations.

Claims (3)

1. a kind of prevent the method for flange defect occur without bottomless drum shape part spinning process, which is characterized in that without bottom cylinder During the blank of shape part carries out reversed spinning, part blank is reserved in the oral area without bottomless drum shape part and is not involved in deformation；

Wherein, in reversed mould pressing, specific steps are as follows:

The position for adjusting spinning roller, is placed in spinning roller except the maximum radius of blank；

Spinning roller carries out axial feed, and the distance of one section of setting is moved forward from the processing starting point of blank；

Start main shaft, blank is circumferentially rotated with main shaft, and spinning roller radial feed presses to the amount of feeding to setting；

Spinning roller carries out axial feed, carries out mould pressing.

2. a kind of as described in claim 1 prevent the method for flange defect, feature occur without bottomless drum shape part spinning process It is, reinforcing rib is set on the part blank that the oral area without bottomless drum shape part is not involved in deformation.

3. a kind of as described in claim 1 prevent the method for flange defect, feature occur without bottomless drum shape part spinning process It is, during multi-pass spinning forming, since intermediate a time, reserves part without the oral area of bottomless drum shape part Blank is not involved in deformation.