SU1237276A1 - Method and apparatus for producing sharply bent branch pipes - Google Patents

Abstract

1. A method for manufacturing steeply-bent nozzles by bending an eccentric tool with the rectilinear section of a tubular billet from the inside, limiting its deformation over the outer diameter, characterized in that, in order to improve performance, quality and efficiency, one end of the tubular billet is distributed to the amount of wall thinning the workpiece during bending without limiting the deformation of the outer diameter, and the next section of the workpiece is subjected to bending with the restriction of its deformation by the outer diameter After that, the remaining rectilinear section is distributed by the amount of pipe wall thinning without limiting the deformation of the outer diameter. 2. A device for making steeply-bent nozzles, comprising a sleeve, an eccentric deforming element, and a pushing sleeve, characterized in that the deforming element is made in the form of a cylindrical rigid core with a cylindrical conical section located at the lower end, and the conical section is located eccentric about the axis of the cylindrical section. (L y oo to O5

Description

I

The invention relates to the processing of metals by pressure and can be used in the manufacture of contactlessly bending pipe nozzles from pipe: billets in various parts of the building industry.

The aim of the invention is to improve the quality by manufacturing steeply-bent nozzles without internal steps, increasing productivity and reducing equipment costs.

FIG. 1 shows a device, a longitudinal section, at the time of loading the first tube; in fig. 2 is a sectional view in FIG. one; in fig. 3 shows a section BB in FIG. 1, at the time of the first transition - the distribution of the lower end of the pipe; in fig. A - the same, at the moment of distribution of the straight pipe section; in fig. 5 - the same, at the moment of the end of the second transition, the flexible nozzle; in fig. 6 - the same, with the pipe bent and the pipe mounted next to the rem before the third transition - the distribution of the straight section of the first pipe left after bending - and at the same time the distribution of the lower end of the pipe following it; in fig. 7 - the same, the end of the first transition for the second pipe; in fig. 8 - ready to branch.

The device contains a rigid core 1 having a cylindrical part for installing the pipe 2. The core .1 is fixed in the annular groove by jaws 3, tucked in springs 4 and having the ability to move along guideways 5 mounted on the support plate 6, when force is applied through pipe 2 to conical parts of the jaws 3. In the upper part of the core 1 there is an annular groove under the jaws 7 mounted on guides 8 mounted on a base plate 9. Guides 8 have a bevel for engagement with wedges 10.

The lower part of the core 1 has a cylindrical juice 11, which is connected through a conical section 12 to a cylindrical part of the core having a diameter equal to the internal diameter of the pipe 2. The diameter of the cylindrical body 11 is greater than the internal diameter of the pipe by the amount of thinning of the pipe wall during bending.

12372762

The maximum amount of thinning of the wall iS of the convex bend contour is related to the geometric dimensions of the resulting pipe by the following expression:

to

15

20

25

thirty

35

40

45

SO

S5

d5

Ai.

R + d

where BD is the wall thickness of the pipe; d is the outer diameter of the pipe; R is the bend radius of the pipe (pipe) along a concave contour.

Tsil: juice ind 11 is located eccentrically relative to the cylindrical part of core 1 and they have a common point of 13 touch, while the eccentricity is equal to half the wall thinning value. The pushing sleeve 14 is attached by a pressure plate 15 to the plate 16, which in turn is attached to the outer slide of the press. The sleeve 17, through which the pipe 2 is pushed, is fastened through the intermediate sleeve 18 to the press ejector, which makes it possible to move and adjust when the pipe is split and bend. The Sugar 19 by means of a bar 20 installed in the guides 21 and connected through the wedge 22 to the inner press slider, serve to interact the sleeves 14 and 17 during the distribution of the end of the pipe 2,.

Base plates 6 and 9 are fastened together with the bottom plate 23 by means of cylindrical columns 24.

The method is carried out as follows.

At the time of loading the pipe (Fig. 1), the first pipe is installed on the cylindrical section of the rigid eccentric core 1 until the lower end stops in the jaws 3, the press slide is moved upwards. After installing the pipes include a downward movement of the external slide. In this case, the wedge 10 compresses the jaws 7, which through the slots in the pushing sleeve 14 enter into the annular groove on the upper end of the core 1 and fix it. With continued movement, the sleeve 14 pushes the pipe 2 down through the sleeve 17 until its lower end stops against the conical section 12 of the core 1, unclenching the clamping jaws 3 and freeing the core 1 (Fig. 3). Sleeve 17, associated with a press ejector, mounted 5

Ai.

R + d

o

five

0

five

0

five

0

five

five

where BD is the wall thickness of the pipe; d is the outer diameter of the pipe; R is the bend radius of the pipe (pipe) along a concave contour.

Tsil: juice ind 11 is located eccentrically relative to the cylindrical part of core 1 and they have a common point of 13 touch, while the eccentricity is equal to half the wall thinning value. The pushing sleeve 14 is attached by a pressure plate 15 to the plate 16, which in turn is attached to the outer slide of the press. The sleeve 17, through which the pipe 2 is pushed, is fastened through the intermediate sleeve 18 to the press ejector, which makes it possible to move and adjust when the pipe is split and bend. The Sugar 19 by means of a bar 20 installed in the guides 21 and connected through the wedge 22 to the inner press slider, serve to interact the sleeves 14 and 17 during the distribution of the end of the pipe 2,.

Base plates 6 and 9 are fastened together with the bottom plate 23 by means of cylindrical columns 24.

The method is carried out as follows.

At the time of loading the pipe (Fig. 1), the first pipe is installed on the cylindrical section of the rigid eccentric core 1 until the lower end stops in the jaws 3, the press slide is moved upwards. After installing the pipes include a downward movement of the external slide. In this case, the wedge 10 compresses the jaws 7, which through the slots in the pushing sleeve 14 enter into the annular groove on the upper end of the core 1 and fix it. With continued movement, the sleeve 14 pushes the pipe 2 down through the sleeve 17 until its lower end stops against the conical section 12 of the core 1, unclenching the clamping jaws 3 and freeing the core 1 (Fig. 3). A sleeve 17, connected to the press ejector, is set so that the lower end of the tube protrudes from it to the length of the straight line to be distributed.

Applying force from the pushing sleeve 14 to the pipe and simultaneously through the crackers 19 to the sleeve 17 (Fig. 4), distribute the straight section of pipe 2 by a rigid eccentric core 1 to the amount of wall thinning while bending without limiting the deformation of the outer diameter. Pipe 2 and the sleeve 17 synchronously moving down. Distribution continues until the lower end of the sleeve 17 is aligned with the lower end of the core 1.

Since the distribution is carried out without limiting the deformation, there is no thinning of the pipe walls. In this case, there is a heterogeneous stress state scheme (the stress along the generator section is tensile and the axial stress is compressive), in connection with which the deformation over the wall thickness is actually zero.

After dispensing the rusks 19 is retracted. To do this, a wedge 22 entering the opening of the bar 20 and pushing the rusks 19 away from the inner slide of the press is driven by the sleeve 14 and pushes the pipe 2 into. the gap between the fixed sleeve 17 and the core 1, the bending of the pipe (Fig. 5) due to the eccentric deformation of the pipe wall and limiting the deformation of the outer diameter of the pipe by the sleeve 17. The movement continues until the sleeve 14 stops against the sleeve 17. After the end of the bending (Fig. 6) both The press slide is retracted to the up position. In this case, the jaws 3 are compressed by the springs 4, and the jaws 7 are unclenched by a wedge 10, the sleeve 14 is pulled off the core 1, the crackers 19 are wedged 22. The next pipe 25 is mounted on the core until its lower end stops in the jaws 3.

When the outer slide slides down, the sleeve 14 pushes the pipe 25 until its lower end stops against the straight section of the pipe 2, the jaw 7 clamping and the sponge 3 apart. The distance between the lower end of the sleeve 17 and the lower end of the core 1 is equal to twice the length handout area.

By applying force to the sleeve 14, push the pipe 25 downward to remove

pipe 2 from the eccentric core (Fig. 7), distributing the remaining straight line section of the pipe and the first straight line section of pipe 25. Dispensing continues until the lower end of the sleeve 17 is aligned with the lower end of the core 2. After this the manufacturing cycle of the pipe is repeated. At the upper end of the finished pipe (Fig. 8), a chamfer is formed due to the eccentric distribution of this end.

Example. Made a pipe with dimensions:

Diameter, mm77t5

Bend Angle ° 90 Bend radius in the middle line, mm .75 Length of the straight line section, mm 20 Wall thickness, mm 5 Material AMgb-M A pipe with a section of 75x5 mm and a length of 100 mm was selected as a blank. The pipe is worn on a rigid eccentric core having a cylindrical section with a diameter equal to the internal diameter of the pipe. The cylindrical juice of the core is conjugated to the cylindrical section along the cone. The diameter of the tube is 2.5 mm larger than the internal diameter of the pipe, i.e. equal to 67.5 mm. The juice is located eccentrically relative to the axis of the cylindrical section by 1.25 mm. The pipe was worn on a rigid core and pushed into the sleeve (the inner diameter of which is equal to the outer diameter of the pipe) so that the lower end of the pipe protruded from the sleeve for a length of the straight line (20 mm).

The end of the pipe was distributed until the lower end of the sleeve was aligned with the lower end of the cylindrical core. The pipe was bent by 90, removed the crackers and: 1 pipe into the gap between the sleeve and the eccentric core. After pulling up the pushing sleeve, the next pipe was put on the core to the upper end of the first pipe and pushed until the first pipe was removed from the eccentric core, distributing the upper end of the first pipe and the lower end of the second one.

The proposed method provides receiving pipes without ledges on the inner surface.

figure 1

sixteen

eleven

2

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2B

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18

Compiled by I. Kovrigina Editor I. Rybchenko Tehred W. Kadar Proofreader. E. Sirokhman Order 3225/10 Circulation 783 Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., d. A / 5

Production and printing company, Uzhgorod, st. Project, 4

Claims (2)

METHOD FOR MANUFACTURING STEEP-BENDED PIPES AND DEVICE FOR ITS IMPLEMENTATION (57) 1. Method for manufacturing steeply bent pipes by bending a straight section of a tube billet with an eccentric tool from the inside, limiting its deformation along the outer diameter, which differs in that in order to increase productivity preliminarily distribute one end of the tubular billet by the amount of thinning of the wall of the billet during bending without limiting the deformation of the outer diameter, and bend the next section of the workpiece with a restriction of its deformation along the outer diameter, after which the remaining rectilinear section is distributed by the amount of thinning of the pipe wall without limiting the deformation of the outer diameter. 2. A device for manufacturing steeply curved nozzles, comprising a sleeve, an eccentric deforming element and a pushing sleeve, characterized in that the deforming element is made in the form of a cylindrical rigid core with a conical and associated cylindrical girdle located at the lower end, while the conical section located eccentrically relative to the axis of the cylindrical section. SU „„ 1237276> The maximum value of wall thinning aS of the convex bending contour is associated with the geometric dimensions of the resulting pipe by the following expression: