Method of tubular blank flange rolling-off

FIELD: process engineering.

SUBSTANCE: invention relates to tube billet flange rolling-off. Blank is subjected to rotary swaging by roller arranged at the angle 25°<β1<30° to blank axis to form truncated cone at its deformable part. Truncated cone section abutting on its base is deformed by forced displacement of the roll located at 8°<β2<12° to blank axis to form preliminary flange. Preliminary flange is deformed to strain-free section of truncated cone by forced displacement of the roller located at 50°<α<70° to blank axis.

EFFECT: expanded performances.

3 dwg, 1 tbl, 1 ex

 

The invention relates to the field of rotary material handling pressure and can be used at the enterprises of machine-building, power engineering, nuclear power engineering, chemical industry and others.

A method of obtaining a stepped shaft [A.S. No. 1773539]. In the way of a cylindrical billet is deformed stationary wedge tool, by moving the workpiece using two drive rollers and its rotation due to contact friction between the wedge surfaces of the tool and the workpiece. The disadvantage of this method is that the structure of the metal clamp remains undeformed and therefore less durable than the rest of the material deformed part. The method has limited technological capabilities in terms of diameter DBclamp diameter DInthe stub part.

A method of obtaining shoulders on the tubular billet rolling, selected as a prototype [Patent RU No. 2304033]. The deformation produced in two stages. The first stage is realized by rotating the landing of the workpiece at an angle of 15°<α1<45° to the axis of the workpiece and receive a truncated cone. In the second stage deform truncated cone movement of the roller at an angle of 45°<α2<75°. In the formation of a truncated cone on its base formed nodules, is characteristic for all processes of rotational deformation of the workpieces. If the elongation of the metal more than 20% (δ≥20%), then flows in the second stage of deformation are eliminated. When the relative elongation of the material is less than 20% (δ<20%), flows are converted into sunsets that lead to the formation of folds and cracks formed on the flanges.

Object of the invention is the expansion of technological possibilities of drifting flanges (shoulders) by providing the possibility of forming flanges on the workpieces from a material with a relative elongation δ<20%.

For solving the problem, a method for rolling flanges of tubular workpieces, including deformation of the workpiece deforming tool by messages of rotation of the workpiece, ensuring synchronous with the workpiece rotation of the deforming tool by contact friction between the deforming tool and the workpiece. Deforming the rotate tool and rotate about the axis of the workpiece, while the deformation of the workpiece is carried out in three stages. The first stage is realized by rotating the landing part of the billet roller angled at 25<β1<30° to the axis of the workpiece, with the formation of the deformable part of a truncated cone. In the second stage deform a section of a truncated cone, adjacent to its base, by means forced displacement of the roll, the location is defined at an angle of 8°< β2<12° to the axis of the workpiece, with the formation of the preliminary flange on the workpiece. In the third stage deform the preliminary flange and the undeformed section of a truncated cone piece by forced displacement of the roller located at an angle of 50°<α<70° to the axis of the workpiece.

The deformation in the second stage at an angle β2prevents the formation of fatal sunset on the basis of a truncated cone. The final formation of the flange is at the third stage roller at an angle α to the axis of the workpiece. Thanks to the corner and there is intense for metal, both in radial and in axial directions. When this radial metal flow provides receiving the radial flange on the median part, and the metal flow in the axial direction leads to the formation of her sleeve. Sequential combined deformation of the workpiece allows to make on the proposed method parts from materials with elongation less than 20%, with flanges at the middle part with respect to the diameter DFflange diameter DBthe stub part detailsDFDB<1,5÷2,0,thus expanding the technological capabilities of a flattening process of shoulders (flanges). The set of distinctive features is necessary and sufficient to solve the task.

At an angle β1between the first deforming roller and the axis of the drive matrix is less than 25° is the deformation in the radial direction, mainly the end part of the workpiece. The angles β1more than 30° leads to the formation, at the base of the truncated cone of the workpiece, the sunsets with a form that cannot be eliminated by subsequent deformation. The use of angles β2between the first deforming roller and the axis of the drive matrix is less than 8° complicates the metal flow in the axial direction. When the angles β2more than 12° sunsets on the surface of the workpiece become a fatal form. The use of angles α between the second deforming roller and the axis of the drive matrix is less than 50° restrict the length of generated stub part ratiolBDF<0,20÷0,22,where lB- the length of the stub part, DF- diameter flange. The use of angles α2more than 70° complicates the metal flow in the radial direction and limits the sizes of flanges formed on the middle portion of the workpiece ratioDF DB<1,2÷1,3.

The device for implementing the method consists of: 1 - deforming roller; 2 - drive matrix; 3 - tubular blank; 4 - ejector; 5 - bearing ejector; 6 - deforming roller (1, 2, 3).

The inventive method is as follows.

The first two stages of preliminary deformation of the workpiece include a message of rotation of the workpiece 3 with providing synchronous with the workpiece rotation deforming roller 1 due to the contact friction between the roller 1 and the workpiece 3 and the local deformation of the workpiece deforming roller 1 mounted for rotation and rotation about the axis of the workpiece (1, 2).

The third stage of the final formation part includes translational movement of the supports of the ejector to the workpiece, rotating the workpiece, ensuring synchronous with the workpiece 3, the rotation of the deforming roller 6 due to contact friction between the roller 6 and the workpiece and the local deformation of the workpiece 3 deforming roller 6 mounted for rotation and rotation about the axis of the workpiece (figure 3).

Deforming roller 1 has a cylindrical shape set at an angle β1to the axis of the workpiece 3. The source of the tubular billet 3 speed is army wear on the rod portion of the ejector 4 and set in the drive matrix 2 on the height of the deformable part. Bearing ejector 5 is supplied to the ejector 4 and is introduced into contact with him to increase the rigidity of the system, the workpiece-tool. Deforming roller 6 is set in the initial position at an angle a to the axis of the workpiece 3. The drive matrix 2 with the workpiece 3 is put into rotation, deforming roller 1 is brought to the workpiece 3, move it under the set angle β1and thus carry out the process of the first stage of the preliminary deformation of the workpiece 3. In the process of deformation of a portion of the exposed area of the tubular billet 3 takes the form of a truncated cone. The shape of a truncated cone creates favorable conditions for the subsequent formation of the flange on the median part.

In the second stage of the deformation of the workpiece, the angle of the deforming roller 1 relative to the axis of the workpiece is changed by the angle β2(figure 2). Deforming roller 1 returned to the formed conical surface of the workpiece 3 at an angle β2deform formed truncated cone and thus carry out the process of the formation of the flange pre-form. The formation of the flange pre-form prevents the formation of sunsets and cracks on the surface made of the flange. In the third stage of the deformation of the workpiece support of the ejector 5 and deformirujuschij roller 6 a is dodat to the workpiece 3 with the flange pre-form, deform the flange pre-form and the undeformed section of a truncated cone. The result is a detail of the required form (figure 3).

An example implementation of the method.

The proposed method has been bushings with flanges, which has dimensions: shown in table 1.

In the table indicated:

β1that β2- the angles between the first deforming roller and the axis of the drive matrix;

α is the angle between the second deforming roller and the axis of the drive matrix;

hF- the height of the flange;

DF- diameter flange;

DB- the outer diameter of the rolled sleeve part;

lIn- the length of the rolled sleeve part;

DNR- inner diameter of the workpiece and details.

Table 1
β1, hailβ2,degα, deghfmmDFmmDBmmlInmmDNRmmDFDB
258506794018251,97
606774020251,92
706754022251,88
10506764019251,90
606754021251,88
70674402325to 1.86
12506754021251,88
60674402325to 1.86
706734025251,83
278506734022251,83
606724024251,80
706714026251,78
10506704023251,76
606694025251,73
706684027251,70
12506694024251,72
606674026251,68
706664028251,65
30 8506654025251,63
606644027251,60
70663402925of 1.57
10506644026251,60
60663402825of 1.57
706624030251,55
12 50663402725of 1.57
606624029251,55
706614032251,52

By rolling parts with specified dimensions used tubular piece of stepped form:

DH- outer diameter shape of the plot of the workpiece installed in the drive matrix, DH=35 mm;

lH- the length of the non-plot harvesting, lH=23 mm;

DD- outer diameter of the deformable section of the billet, DD=45 mm;

lD- the length of the deformable section of the billet, lD=25 mm

The workpiece materials - brass Lmcs-2-2, with characteristics: elongation δ=8÷10%, the tensile strength σIn=300÷350 MPa. The scope of brass Lmcs-2-2: bushings and other parts [GOST 17711-72].

At the first stage of the deformation of the workpiece implemented process ro is sure the landing of the exposed area of the tubular workpiece deforming roller 1, set at an angle β1to the axis of the workpiece. In the process of deformation of a portion of the exposed area of a tubular piece takes the form of a truncated cone.

In the second stage of the deformation of the workpiece implemented process rotary planting area adjacent to the base is formed of a truncated cone workpiece deforming roller 1 mounted at an angle β2to the axis of the workpiece and the forming of the flange pre-form.

The third stage is implemented process of radial-axial rotation of the pressing roller 6 mounted at an angle a to the axis of the workpiece. In the moment of final shaping, the details of the requisite shape, the dimensions of the flange and the stub portion. Details of the defects have not.

- Implemented method of rolling the flanges provides the possibility of forming a flange on the blanks of materials with different relative elongation δ and expanding technological possibilities of the method.

The method of rolling the flanges of tubular workpieces, including deformation of the workpiece deforming tool by messages of rotation of the workpiece, ensuring synchronous with the workpiece rotation of the deforming tool by contact friction between the deforming tool and the workpiece, while the deforming tool rotate and turn carries the flax axis of the workpiece, characterized in that the deformation of the workpiece is carried out in three stages and the first stage is realized by rotating the landing part of the billet roller, angled 25°<β1<30° to the axis of the workpiece, with the formation of the deformable part of a truncated cone, the second stage is deformed section of a truncated cone, adjacent to its base, by means forced displacement of the roller located at an angle of 8°<β2<12° to the axis of the workpiece, with the formation of the preliminary flange on the workpiece, and the third stage deform the preliminary flange and the undeformed section of a truncated cone piece by forced displacement of the roller located at an angle of 50°<α<70° to the axis of the workpiece.



 

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