CN1454730A - Diagonal wedge continuous-rolling shaping method - Google Patents

Abstract

The invention provides a wedge continuous rolling forming method. It is characterized in that: a pair of rolls with the same pass shape rotate at the same speed in the same direction, and the angle θ between the roll axis in space is 2 to 8 degrees. The determined deformation direction of the material is opposite to the feeding direction of the rolled piece. The forming area of the roll is 360-1080 degrees. The roll produces one product per revolution. When the rolling is completed, both ends of the rolled piece are cut off at the same time; the advantages of the present invention are: The rolling forming process has a relatively simple roll design, a large complex coefficient of the rolled product, and a greatly improved product precision. It is suitable for thermoplastic forming of shaft parts with a relatively short length and diameter.

Description

A kind of oblique wedge continuous rolling forming method

Technical field:

The invention belongs to the technical field of metal plastic forming, and in particular provides a wedge continuous rolling forming method. It involves continuous plastic forming of shaft parts, especially the thermoplastic forming of shaft parts with shorter aspect ratio (length-to-diameter ratio refers to the ratio of length to diameter).

technical background:

Part rolling technology (cross-wedge rolling and cross-wedge rolling) is an advanced technology for plastic forming of shaft parts, and the cross-rolling process is more suitable for shaft parts with relatively short aspect ratios. Cross-rolling technology needs to accurately calculate the volume of the product material contained in each section of the mold cavity when designing the mold. Due to the complex spatial relationship, this will be a very difficult thing, especially when trying to accurately form products with complex shapes. difficulty. In addition, the skew rolling process cannot control the axial force inside the rolled piece during rolling, and in some cases it is easy to produce porosity or holes in the center of the product.

Contents of the invention

The purpose of the present invention is to provide a method for continuous forming of wedges, which solves the problem of accurately forming complex-shaped products with relatively short length and diameter, makes the mold design relatively simple, and can produce complex-shaped products in large quantities, high efficiency, high precision, and continuously .

The structure of the present invention is: a pair of rollers with the same pass shape rotate in the same direction and at the same speed. The intersecting angle θ of the roll axis in space is 2-8 degrees. The roll pass consists of classic cross-rolled ribs and forming wedges. The material deformation direction determined by the forming wedge is opposite to the feeding direction of the rolled piece. The forming area of the roll is between 360 and 1080 degrees, and the roll produces one product per revolution. When the rolling is completed, both ends of the rolled piece are cut off at the same time. The specific process is as follows:

As shown in Figure 1, two rolls 1 and 3 with the same helical wedge pass, their axes intersect each other in the vertical plane projection of the two rolls (see Figure 2), the two rolls turn in the same direction, and the raw material 2 reverses under the action of the rolls. Rotate in the opposite direction, and move axially along the center line of the projected intersection angle of the two rolls, and form a rotary part product 8 every time the roll rotates.

The surface of the roll consists of the basic pass and basic pitch corresponding to the shape of the product, the forming wedge 4, 7 whose width direction is opposite to the feeding direction of the rolled piece, the front and rear cutting ribs 5, 6 of the rolled piece, the guide groove 9, classic cross rolling Composed of 10 ribs.

The forming wedge 4 faces a forming surface with an included angle α between the rolling piece feeding direction and the roll axis, and the included angle α is 15 to 60 degrees. There is a widening angle with an angle β of 2-10 degrees between the forming surface and the basic helical lead of the roll. Under the action of the α forming surface, the metal is sent to the rolled piece and compressed in the opposite direction, and the diameter of the rolled piece reaches the predetermined size, and it is finished and formed under the action of the roll surface 7. This part generally does not need to calculate the volume. If the part includes a part that needs to be further rolled with a classic cross-rolled rib, then only the volume of this part needs to be included in the calculation.

The forming wedge 7 is composed of a helical surface with constant height, which is consistent with the shape of the rolling part.

The classic cross-rolling rib 10 calculates the rib width according to the classic cross-rolling equal-volume theory, and changes the screw pitch on the feeding side of the rib. Classical cross-rolled ribs are generally used when the width of the rolled piece is not large and the reduction in area is large. After the pitch of the rib is changed, the pitch of all the roll grooves on its feed side is changed accordingly.

The front and rear cutting ribs 5 and 6 of the rolled piece are at the exit of the roll, and a pair of thinner cutter ribs are rapidly raised from the front and rear two ribs near the finished rolled piece to cut off the front and rear connecting diameters of the rolled piece at the same time. The connection diameter is generally rolled by the classic skew rolling method.

The width and shape of the guide groove 9 are generally determined by the profile at the largest diameter of the rolled piece. Its function is to bite into a part of the material to balance the reverse force of the α forming surface, and guide the rolled piece to advance along the spiral groove of the roll.

The advantages of the present invention are:

1. The wedge-shaped convex part whose deformation direction of the material is opposite to the feeding direction of the rolled piece is used to replace the classic cross-rolled convex rib, which greatly reduces the volume calculation that must be done when designing the roll, and makes the roll design work easier.

2. Reduce the complex volume calculation, that is, reduce the design error. It makes it possible to roll complex products, and the product precision is greatly improved.

3. Adopting the method of combining forming wedges and classic convex ribs, the rolling process is completed in more than one turn of the roll, and the front and rear ends are cut off at the same time. It can roll complex products with large section reduction rate, and make the two ends of the products smooth and tidy.

4. Changing the angle of the wedge can change the stress-strain state inside the rolled piece, so as to effectively control and improve the internal quality of the product.

5. The rolling process is carried out continuously. When the previous rolled piece is not formed, the next rolled piece has started rolling, and the connection diameter is small, saving materials.

6. As long as the shape and position of the protrusion of the forming wedge 7 and the classic rib 10 are changed, the shape of the product can be changed and different products can be produced.

Description of drawings:

Fig. 1 is a schematic diagram of the forming method of the present invention. Roll 1, 3, raw material 2, forming wedge 4, 7, cutting rib 5, 6, guide groove 9, classic cross-rolling rib 10, and component products 8. β is the angle between the forming surface and the basic helical lead of the roll.

Figure 2 is a schematic diagram of the spatial position of the rolls. The forming wedge 4 faces a forming surface with an angle α between the feeding direction of the rolling piece and the axis of the roll, and θ is the angle at which the axis of the roll intersects in space.

Claims (5)

1. A wedge continuous rolling forming method, characterized in that: a pair of rolls with the same pass shape rotate at the same speed in the same direction, the intersecting angle θ of the axes of the rolls in space is 2 to 8 degrees, and the pass shape of the rolls is changed from the classic inclined Composed of rolling ribs and forming wedges, the material deformation direction determined by the forming wedges is opposite to the feeding direction of the rolled piece. The forming area of the roll is 360-1080 degrees. The roll produces one product per revolution. When the rolling is completed, the rolled piece The two ends are cut off at the same time; the specific rolling forming process is: two rolls (1) and (3) with the same spiral wedge pass, their axes intersect each other in the vertical plane projection of the two rolls, and the two rolls turn to the same direction, The raw material (2) rotates in reverse under the action of the rolls, and moves axially along the center line of the projected intersection angle of the two rolls. The forming area of the rolls is between 360 and 1080 degrees, and the rolls rotate once to form a rotary part product (8). 2. The wedge continuous rolling forming method according to claim 1, characterized in that: the surface of the roll consists of a basic pass and a basic pitch corresponding to the shape of the product, and the forming wedge ( 4, 7), the front and rear cutting ribs (5, 6) of the rolled piece, the guide groove (9), and the classic oblique rolling rib (10); the forming wedge (4) faces the feeding direction of the rolled piece and the axis of the roll There is a forming surface with an included angle α, and the included angle α is 15 to 60 degrees. There is a widening angle with an angle β of 2 to 10 degrees between the forming surface and the basic spiral lead of the roll. Under the action of the α forming surface, the metal direction The rolled piece is compressed in the opposite direction, and the diameter of the rolled piece reaches the predetermined size, and it is finished and formed under the action of the roll surface (7). 3. The wedge continuous rolling forming method according to claim 1 or 2, characterized in that: the top surface (7) of the forming wedge is composed of a helical surface with a constant height, which is consistent with the shape of the rolling part; 4. According to claim 1 or 2, the oblique wedge continuous rolling forming method is characterized in that: the classical oblique rolling rib (10) calculates the rib width according to the classic oblique rolling equal volume theory, and Change the pitch. 5. The oblique wedge continuous rolling forming method according to claim 1 or 2, characterized in that: the front and rear cutting ribs (5, 6) of the rolled piece are at the exit of the roll, and the front and rear two ribs are close to the finished rolled piece side Quickly raise a pair of thinner cutter ribs to cut off the front and rear connecting diameters of the rolled piece at the same time. The connecting diameters are generally rolled by the classic cross-rolling method. 6. The wedge continuous rolling forming method according to claim 1 or 2, characterized in that: the width and shape of the guide groove (9) are determined by the shape of the maximum diameter of the rolled piece, and its function is to bite into a part of the material To balance the reverse force of the α forming surface, guide the rolled piece to advance along the spiral groove of the roll.

Images