RU2759144C1 - Method for manufacturing axisymmetric shells with internal riffles - Google Patents

Abstract

FIELD: mechanical engineering.

SUBSTANCE: invention relates to a method for manufacturing axisymmetric shells with internal riffles. The expected result is achieved by a method that includes blank and pressure processing with the formation of spiral corrugations of the opposite direction on the inner surface of the workpiece in two operations, first with a punch equipped with forming protrusions of the right, then of the left direction, when the punch and the workpiece are moved together through a matrix with a calibration hole of a larger, then smaller diameter. At the same time, the pipe is cut into cut-to-length sections, mechanical processing is performed with the formation of a ledge on the inner surface of the workpiece and phosphating. Then, the workpiece is installed in the device until the punch stops at the ledge of the workpiece and the riffles are formed in one or more transitions at each operation of pressure processing by means of a punch and a matrix. Moreover, the forming protrusions of the punch are made of a trapezoidal profile with anterior and posterior conical sections with an angle of 25-35°, conjugated with a cylindrical section with a length of 0.1-0.7 mm. The working surface of the matrix is made of a trapezoidal profile with anterior and posterior conical sections with an angle of 5-15°, conjugated along a radius of 0.5-2 mm with a cylindrical section, 2-7 mm long. An antifriction fluorine-containing coating is applied to the working surfaces of the punch and matrix, and during the formation of riffles, a fluorine-containing lubricant emulsion based on perfluoropolyether acid and industrial oil is applied to the working surfaces of the punch and matrix and to the outer surface of the workpiece.

EFFECT: increase in the accuracy and quality of the parts obtained, as well as an increase in manufacturing productivity and the metal utilization factor.

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Description

The invention relates to the field of metal processing by pressure, namely to the manufacture of axisymmetric shells with internal grooves, which have the form of spiral depressions of the counter right and left directions by pressure treatment on presses and on pressure-rolling machines, which is a complex technical problem due to large efforts of shaping and forces friction, leading to a decrease in dimensional accuracy and the quality of the processed surface of the grooves.

A known method of manufacturing shells with internal grooves in the form of protrusions and depressions, described in the book by M.A. Greditor "Pressing works and rotary extrusion", "Mechanical engineering", Moscow, 1971, p. 117, fig. 69, which consists in forming an annular blank by the pressure rollers. At position 11, annular recesses and protrusions are formed on the inner surface of the workpiece, which is elongated in the axial direction.

The disadvantages of this method include the impossibility of forming by this method spiral grooves of the opposite direction on the inner surface of the workpiece.

The closest in technical essence is the "Method for the manufacture of shells", according to RF patent No. 2171445, publ. 07/27/2001, BI No. 21.

This method is carried out in two successive operations by pressure treatment of a tubular billet with a bottom mounted on a punch equipped with shaping protrusions, while moving together through a calibration die with the punch resting against the bottom of the billet.

The shaping spiral protrusions of the punches have an opposite - right or left direction.

The grooves inside the workpiece are formed due to the radial flow of the metal when moving through the calibrating die, the diameter of which in the first operation is greater than the diameter of the die in the second operation.

After the completion of the formation of spiral grooves at each operation, the workpiece and the punch are removed from the matrix and the punch is removed from the workpiece when it rests against the annular stripper.

This method was adopted by the authors as a prototype.

As can be seen from this technical solution, the process of forming the riffle is carried out with the punch against the bottom of the workpiece in two operations, first the riffles of the right, then the left direction are formed.

The disadvantage of this method, taken as a prototype, is a low metal utilization rate, since a tubular billet with a bottom is obtained by extrusion by pressing from a circle.

In addition, the main disadvantage of this method is the low resistance of the working surfaces of the deforming tool of the punch and matrix due to the high frictional force during the formation of the grooves and when removing the workpiece from the punch, which leads to a deterioration in the quality of the processed surface of the workpiece and a decrease in the dimensional accuracy of the shells due to distortion of the groove profile, as well as rapid wear of the punch protrusions and the working surface of the matrix.

The task of this technical solution, adopted by the authors as a prototype, was to develop a method for manufacturing axisymmetric shells with a bottom with internal grooves in order to expand the functional and technological capabilities of the method.

The invention relates to methods for manufacturing axisymmetric casings with internal grooves by pressure treatment with the formation of spiral grooves of opposite right and left directions and can be used in the manufacture of such casings in various fields of industry.

Common features with the method of manufacturing shells with internal grooves proposed by the authors is the presence of a blank operation for obtaining an axisymmetric workpiece and forming on the inner surface of the workpiece spiral grooves of the opposite direction in two operations, first with a punch equipped with shaping protrusions of the right, then left direction, with the joint movement of the punch with the workpiece through a calibrating die of a larger, then a smaller diameter.

Unlike the prototype, in the method proposed by the authors for the manufacture of axisymmetric shells with internal grooves, the pipe is cut into dimensional workpieces, machining is performed with the formation of a step on the inner surface of the workpiece and phosphating, then the workpiece is installed in the device until the punch stops in the workpiece shoulder and the riffles are formed in one or several transitions at each operation of pressure processing by means of a punch and a matrix, on the working surfaces of which an antifriction fluorine-containing coating is applied, while in the process of forming a riffle, a fluorine-containing lubricating emulsion based on perfluoropolyether acid and industrial oil is applied to the working surfaces of the punch and matrix and on the outer surface of the workpiece.

In particular cases, that is, in specific embodiments, the invention is characterized by the following features:

- the shaping protrusions of the punch are trapezoidal with front and rear conical sections with an angle of (25-35) °, conjugated with a cylindrical section with a length of (0.1-0.7) mm;

- the working surface of the dies is made of a trapezoidal profile with front and rear conical sections with an angle (5-15) °, conjugated along the radius (0.5-2) mm with a cylindrical section with a length of (2-7) mm;

- the formation on the inner surface of the blanks of the right, then the left direction is performed on a press-rolling machine with deforming rollers on a punch with shaping protrusions of the right, then left direction;

- the formation on the inner surface of the blanks of the right, then the left direction is performed on a pressure-rolling machine with deforming rollers of a trapezoidal profile with front and rear conical sections with an angle of (10-15) °, conjugated along a radius (2-5) mm with a cylindrical section of length (5-10) mm;

- as an antifriction fluorine-containing coating of the working surfaces of the deforming tool, a solution of technical acid 6MFK-180 with a mass fraction of a fluorine-containing substance (2.0-2.5)% in the freon composition "Kh13KNNKh" is used;

- on the working surfaces of the deforming tool and on the outer surface of the workpiece, a fluorine-containing lubricant emulsion is applied, which is a composition (0.4-4)% of technical acid 6MFK-180 in industrial oil.

This is what allows us to conclude that there is a causal relationship between the set of essential features of the proposed technical solution and the achieved technical result.

The specified features, distinguishing from the prototype and which are covered by the requested scope of legal protection, are sufficient in all cases.

The objective of the present invention is to provide the possibility of manufacturing axisymmetric shells with internal grooves by pressure treatment with high dimensional accuracy and quality of the processed surface, to increase production productivity and metal utilization factor.

The specified technical result in the implementation of the invention is achieved by the fact that in the known method, including blank and pressure processing with the formation on the inner surface of the workpiece spiral grooves of the opposite direction in two operations, first with a punch equipped with shaping protrusions of the right, then the left direction, with the joint movement of the punch with a workpiece through a calibrating matrix of a larger, then a smaller diameter, the peculiarity is that the pipe is cut into dimensional workpieces, machining is performed with the formation of a step on the inner surface of the workpiece and phosphating, then the workpiece is installed in the device until the punch stops against the workpiece ledge and riffles are formed behind one or more transitions at each pressure treatment operation by means of a punch and a matrix, on the working surfaces of which an antifriction fluorine-containing coating is applied, while in the process of forming a groove on the working surfaces of the punch and matrix and on the outer surface of the workpiece is applied a fluorine-containing lubricating emulsion based on perfluoropolyether acid and industrial oil.

The new set of operations, as well as the presence of links between them, allows, in particular, due to:

- cutting the pipe into dimensional workpieces to increase the metal utilization rate;

- machining with the formation of a ledge on the inner surface of the workpiece to increase the metal utilization rate;

- phosphating of workpieces to reduce the frictional force during pressure processing;

- installing the workpiece in the device until the punch stops in the workpiece ledge to ensure constant contact between the workpiece and the punch when moving the workpiece with the punch through the die;

- the formation of riffles in one or several transitions at each operation of pressure treatment to expand the technological capabilities of the method;

- the formation of corrugations by means of a punch and matrix, on the working surfaces of which an antifriction fluorine-containing coating is applied, to ensure the formation of a wear-resistant layer on the contact working surfaces, which reduces friction and enhances the protection of surfaces from wear, as well as to reduce friction caused by high contact stress and increased surface temperature, both due to heat transfer, and due to the movement and deformation of the processed material;

- applying on the working surfaces of the punch and matrix and on the outer surface of the workpiece during the formation of the fluorine-containing emulsion of a lubricant based on perfluoropolyether acid and industrial oil to reduce the friction force and adhesive interaction between the tool and the part, which leads to a decrease in the processing force and a decrease in the adhesion of two contact surfaces at friction, a decrease in the roughness of the processed surface of the shell and a decrease in wear of the working surfaces of the punch and matrix.

The features that characterize the invention in specific embodiments allow, in particular, due to:

- execution of the shaping protrusions of the trapezoidal punch with front and rear conical sections with an angle of (25-35) °, conjugated with a cylindrical section with a length of (0.1-0.7) mm to ensure high stability of the process of formation of the corrugation, with the values of the front and rear conical sections less than 25 ° and the length of the cylindrical section less than 0.1 mm, chipping of the forming protrusions of the punch occurs, the formation of burrs on the processed surface and the violation of the dimensional accuracy of the groove profile, and at angles more than 35 ° and the length of the cylindrical section more than 0.7 mm, the forming force increases riffle and friction force, which leads to rapid abrasive wear of the shaping protrusions of the punch, the formation of corrugations and sagging on the treated surface and a violation of the dimensional accuracy of the riffle profile;

- execution of the working surface of the trapezoidal profile matrices with the front and rear conical sections with an angle (5-15) °, conjugate along the radius (0.5-2) mm, with a cylindrical section with a length of (2-7) mm to ensure the stability of the process of shaping the grooves on the inner surface of the workpiece as a result of a smooth increase in deformations when moving the workpiece with a punch along the working surface of the matrix;

- forming on the inner surface of the workpieces, at first, the riffle of the right, then the left direction on the press-rolling machine to expand the technological capabilities of the method, in addition, the process of pressing processing on the press-rolling machine is characterized by less force and less friction force than on the press, which is due to the presence of local zones deformation centers of rollers in the workpiece;

- forming on the inner surface of the blanks the riffles of the right, then the left direction on the press-rolling machine with deforming rollers on the punch with shaping protrusions of the right, then the left direction to obtain on the inner surface of the blanks the riffles of the right, then the left direction with high dimensional accuracy and quality of the processed surface;

- forming on the inner surface of the blanks of the right, then the left direction on the press-rolling machine by deforming rollers of a trapezoidal profile with front and rear conical sections with an angle of (10-15) °, conjugated along a radius (2-5) mm with a cylindrical section of length ( 5-10) mm, to ensure the stability of the process of shaping the grooves on the inner surface of the workpiece as a result of a smooth increase in deformation when the rollers move along the outer surface of the workpiece along the working surface of the punch;

- use as an antifriction fluorine-containing coating solution of technical acid 6MFK-180 with a mass fraction of fluorine-containing substance (2.0-2.5)% in the freon composition "Kh13KNNKH" the concentration of a fluorine-containing substance in this particular range on the working surface of the tool creates conditions that reduce friction and heat transfer, which is a significant condition for the cost-effective operation of the tool;

- applying on the working surfaces of the deforming tool and on the outer surface of the workpiece a fluorine-containing lubricant emulsion, which is a composition of (0.4-4)% perfluoropolyether acid 6MFK-180 technical in industrial oil, increase the wear resistance of the deforming tool, eliminate the destruction of contact surfaces, reduce the temperature of the surface layer, which leads to a decrease in friction, and allows you to increase the economic efficiency of the tool by increasing wear resistance, with the content of perfluoropolyether acid 6MFK-180 technical less than 0.4% in the emulsion, the effect is insignificant, and with a content of more than 4%, there is no increase in the economic efficiency of the tool wear resistance, since the consumption of perfluoropolyether acid increases.

Features that distinguish the proposed technical solution from the prototype are not identified in other technical solutions and are not known from the prior art in the process of patent research, which allows us to conclude that the invention meets the criterion of "novelty".

Investigating the state of the art in the course of conducting a patent search on all types of information available in the countries of the former USSR and foreign countries, it was found that the proposed technical solution does not explicitly follow from the current state of the art, therefore, it can be concluded that the criterion "inventive step ".

The essence of the invention lies in the fact that in the method of manufacturing axisymmetric shells with internal grooves, the pipe is cut into dimensional workpieces, machining is performed with the formation of a step on the inner surface of the workpiece and phosphating, then the workpiece is installed in the device until the punch stops in the workpiece shoulder and the riffles are formed in one or several transitions at each operation of pressure processing by means of a punch and a matrix, on the working surfaces of which an antifriction fluorine-containing coating is applied, while in the process of forming a groove, a fluorine-containing lubricating emulsion based on perfluoropolyether acid and industrial oil is applied to the working surfaces of the punch and matrix and on the outer surface of the workpiece.

The essence of the invention is illustrated by drawings, where FIG. 1 shows the process of forming internal corrugations of the right direction on a pipe billet 1 with a diameter D _o (mm) by a punch 2 with an emphasis on the ledge G of a workpiece 1 during its joint advance with a punch 2 in a matrix 3.

α ₁ - the front angle of the conical section of the profile of the matrix 3;

β ₁ - the rear angle of the conical section of the profile of the matrix 3;

α _{1 (mm)} is the length of the cylindrical section of the profile of the matrix 3;

R _{m (mm)} - radius of conjugation of the front and rear conical sections of the profile of the matrix 3 with the cylindrical section;

D _{1 (mm)} - diameter of the calibrating hole of the matrix 3;

γ - front and rear angle of the tapered sections of the profile of the shaping protrusions of the punch 2 (section D-D) in Fig. 1;

b _(mm) is the length of the cylindrical section of the profile of the shaping protrusions of the punch 2 (section D-D) in FIG. 1;

D _{p (mm)} - punch diameter 2;

A - working surfaces of the punch 2;

B - working surfaces of the matrix 3;

B - the outer surface of the workpiece 1;

4 - bandage;

5 - puller;

6 - workpiece with inner grooves of the right direction;

P _{(t / s)} - press effort.

FIG. 2 shows the process of forming internal corrugations of the left direction on a pipe billet 6 with a diameter D _{1 (mm) by a} punch 7 with an emphasis on the ledge G of the workpiece 6 during its joint advancement with a punch 7 in the matrix 8.

α ₁ - front angle of the tapered section of the profile of the matrix 8;

β ₁ - the rear angle of the tapered section of the profile of the matrix 8;

a _{(mm) 1} - the length of the cylindrical section of the profile of the matrix 8;

D _{2 (mm)} - diameter of the calibrating hole of the matrix 8, D _{2 (mm)} <D _{1 (mm)} (Fig. 1);

R _{m (mm)} - radius of conjugation of the front and rear conical sections of the profile of the matrix 8 with the cylindrical section;

γ - front and rear angle of the profile of the shaping protrusions of the punch 7 (section K-K) in Fig. 2;

b - the length of the flat top of the shaping protrusions of the punch 7 (section K-K) in Fig. 2;

D ' _{p (mm)} - punch diameter 7, D' _{p (mm} ) <D _{p (mm)} (Fig. 1);

E - working surfaces of the punch 7;

W - working surfaces of the matrix 8;

З - the outer surface of the workpiece 6;

9 - bandage;

10 - puller;

11 - workpiece with inner grooves of the right and left directions;

And - the inner surface of the workpiece 11 (breakout L);

P _{(t / s)} - press effort.

FIG. 3 shows the process of forming inner corrugations of the right direction on a tubular billet 12 with a diameter D _{o (mm) by} deforming rollers 13 when they move along the outer surface of the billet 12 with the punch 14 stop against the ledge G of the billet 12 in the direction of the spindle 15 of the press-rolling machine.

α ₂ - the front angle of the tapered section of the profile of the rollers 13;

β ₂ - the rear angle of the tapered section of the profile of the rollers 13;

a _{2 (mm)} is the length of the cylindrical section of the profile of the rollers 13;

R _{p (mm)} - radius of conjugation of the front and rear conical sections of the profile of the rollers 13 with the cylindrical section;

γ - front and rear angle of the profile of the shaping protrusions of the punch 14 (section П-П) of FIG. 3;

b _(mm) is the length of the cylindrical section of the profile of the shaping protrusions of the punch 14- (section P-P) in FIG. 3;

D _{p (mm)} - punch diameter 14; 15 spindle;

16 - clamp;

17 - puller;

18 - billet with inner grooves of the right direction;

D _{1 (mm)} - the outer diameter of the workpiece 18;

M - working surfaces of the punch 14 (section P-P) of Fig. 3;

H - working surfaces of rollers 13;

About - the outer surface of the workpiece 12;

F _{(mm / min)} - axial feed of rollers 13;

n ( _min ^-1 ) - spindle rotation speed 15.

FIG. 4 shows the process of forming the left-hand groove on the workpiece 18 by deforming rollers 19 when they move towards the spindle 21 of the press-rolling machine with the punch 20 stop against the step G of the workpiece 18.

α ₂ - rake angle of the tapered section of the profile of the rollers 19;

β ₂ - the rear angle of the tapered section of the profile of the rollers 19;

a _{2 (mm)} is the length of the cylindrical section of the profile of the rollers 19;

R _{p (mm)} - radius of conjugation of the front and rear conical sections of the profile of the rollers 19 with the cylindrical section;

D _{1 (mm)} - workpiece diameter 18;

D _{2 (mm)} - diameter of the workpiece 24 with grooves of the right and left directions;

γ is the profile angle of the front and rear conical sections of the shaping protrusions of the punch 20 (section U-U) in FIG. 4;

b _(mm) is the length of the cylindrical section of the profile of the shaping protrusions of the punch 20 (section U-U) in FIG. 4;

D ' _{p (mm)} - punch diameter 20, D' _{p (mm)} <D _{p (mm)} (Fig. 3);

21 - spindle;

22 - clamp;

23 - puller;

24 - workpiece with inner grooves of the right and left direction; P - working surfaces of the punch 20 (section U-U) of Fig. 4;

C - working surfaces of rollers 19; T is the outer surface of the workpiece 18;

X - the inner surface of the workpiece 24 with corrugations of the right and left directions (breakout F);

F _{(mm / min)} - axial feed of rollers 19; n ( _min ^-1 ) - spindle rotation speed 21.

The above-described method of manufacturing axisymmetric casings with internal grooves is carried out as follows.

The original workpiece 1 is obtained by cutting pipes into dimensional workpieces on a pipe cutting machine.

Perform machining with the formation of the step G (figure 1) on the inner surface of the workpiece 1 on a lathe. The workpieces are phosphated in baths. Antifriction fluorine-containing coating is applied to the working surfaces A of the punch 2 (Fig. 1) and to the working surfaces B of the matrix 3.

The workpiece 1 (figure 1) is installed in the press fixture until the punch 2 stops in the ledge G of the workpiece 1.

Under the action of the force P _{t / s of the} working stroke of the press, the punch 2 with the workpiece 1 are jointly moved through the calibrating hole of the matrix 3 with a diameter D _{1 (mm)} .

For one or more transitions of the working stroke, a workpiece 6 with a diameter D _{1 (mm} ) with internal grooves of the right direction is obtained (Fig. 1).

In the process of forming the corrugation, a fluorine-containing lubricating emulsion based on perfluoropolyether acid and industrial oil is applied to the working surfaces A of the punch 2, to the working surfaces B of the matrix 3 and to the outer surface B of the workpiece 1.

After the completion of the formation of the corrugation during the reverse stroke of the press, the workpiece 6 is removed from the punch 2 when the workpiece 6 rests against the end of the stripper 5.

Then perform the second operation of forming the corrugation of the left direction (figure 2).

Billets 6 are phosphated in baths.

Antifriction fluorine-containing coating is applied to the working surfaces E of the punch 7 and to the working surfaces Zh of the matrix 8.

The workpiece 6 (figure 2) is installed in the press fixture until the punch 7 stops in the ledge G of the workpiece 6.

Under the action of the force P _{(t / s) of the} working stroke of the press, the punch 7 with the workpiece 6 are moved together through the calibrating hole of the die 8 with a diameter D _{2 (mm)} .

For one or several transitions of the working stroke, a workpiece 11 with internal grooves of the right and left directions is obtained - surface I (breakout L) of Fig. 2.

In the process of forming the corrugation on the working surfaces E of the punch 7 (section K-K) of Fig. 2, on the working surfaces of the G matrix 8 and on the outer surface 3 of the workpiece 6, a fluorine-containing lubricating emulsion based on perfluoropolyether acid and industrial oil is applied.

After the completion of the formation of the corrugation during the reverse stroke of the press, the workpiece 11 is removed from the punch 7 when the workpiece rests on the end of the stripper 10.

Alternatively, the formation of grooves on the inner surface of axisymmetric shells on a press-rolling machine is performed as follows.

Pipes are cut into dimensional blanks on a pipe cutting machine.

Perform mechanical processing on a lathe with the formation of a step G on the inner surface of the workpiece 12 (figure 3).

Billets 12 are phosphated in baths. Antifriction fluorine-containing coating is applied to the working surfaces M of the punch 14 and to the working surfaces H of the rollers 13.

The workpiece 12 is installed on a punch 14 with shaping protrusions of the right direction with an emphasis on the ledge G and a clamp 16 is fixed on the punch 14.

With the axial movement of the rollers 13 in the direction of the spindle 15 in one or several transitions, the formation of the corrugation of the right direction is carried out.

Get a workpiece 18 with a diameter D _{1 (mm)} with grooves in the right direction.

In the process of forming the corrugation on the working surfaces M of the punch 14, on the working surfaces H of the rollers 13 and on the outer surface O of the workpiece 12, a fluorine-containing lubricating emulsion based on perfluoropolyether acid and industrial oil is applied.

After completing the formation of the corrugation, the rollers 13 are retracted to their original position and the workpiece 12 is removed from the punch 14 with the stripper 17.

The formation of the corrugation of the left direction on the inner surface of the workpiece 18 (Fig. 4) on the press-rolling machine is carried out as follows.

Billets 18 are phosphated in baths. Antifriction fluorine-containing coating is applied to the working surfaces P of the punch 20 (section Y-Y) of Fig. 4 and to the working surfaces C of the rollers 19.

The workpiece 18 is installed on the punch 20 with the shaping protrusions of the left direction with an emphasis on the ledge G.

Press 22 the workpiece 18 is fixed on the punch 20.

With the axial movement of the rollers 19 in the direction of the spindle 21 in one or several transitions, the corrugation of the left direction is formed.

Get a workpiece 24 with a diameter D _{2 (mm)} with corrugations of the right and left directions on the inner surface X (breakout F) of Fig. 4.

In the process of forming the corrugation on the working surfaces P of the punch 20, on the working surfaces C of the rollers 19 and on the outer surface T of the workpiece 18, a fluorine-containing lubricating emulsion based on perfluoropolyether acid and industrial oil is applied.

After completing the formation of the grooves, the rollers 19 are retracted to their original position and the workpiece 24 is removed from the punch 20 with a stripper 23.

Example 1

The original billet is obtained by cutting steel pipes into dimensional billets on a pipe cutting machine. Mechanical processing is performed on a lathe to obtain a step G on the inner surface of the blanks 1, 6 (Fig. 1), (Fig. 2).

Billets 1, 6 are phosphated in baths.

On the working surfaces A, E of the punches 2, 7 and on the working surfaces B, G of the matrices 3, 8 (Fig. 1), (Fig. 2), an antifriction fluorine-containing coating is applied to the technical acid solution 6MFK-180 with a mass fraction of a fluorine-containing substance 2.3 % in the Kh13KNNH freon composition.

On a hydraulic press, in two operations, in one or several transitions, at each operation, riffles of the right, then the left direction are formed.

When forming the corrugation of the right and left directions, punches 2, 7 are used (Fig. 1), (Fig. 2) with shaping protrusions of a trapezoidal profile with anterior and posterior angles γ = 30 ° of conical sections conjugated with a cylindrical section of length b = 0.5 _mm , as well as matrices 3, 8 (Fig. 1), (Fig. 2) of a trapezoidal profile with a front conical section with an angle α ₁ = 7 °, with a rear conical section with an angle β ₁ = 7 ° and with a conjugation radius R _m = 1 _mm with a cylindrical section of length a1 = 5 _mm .

In the process of forming the corrugation on the working surfaces A, E of the punches 2, 7 and on the working surfaces B, G of the matrices 3, 8, as well as on the outer surfaces B, 3 of the blanks 1, 6 (Fig. 1), (Fig. 2) fluorine-containing lubricant emulsion - composition of 2% perfluoropolyether acid 6MFK-180 technical in industrial oil.

Example 2

The original billet is obtained by cutting steel pipes into dimensional billets on a pipe cutting machine.

Mechanical processing is performed on a lathe to obtain a step G on the inner surface of the blanks 12, 18 (Fig. 3), (Fig. 4).

Billets 12, 18 are phosphated in baths.

On the working surfaces M, R of punches 14, 20 and on the working surfaces H, C of rollers 13, 19 (Fig. 3), (Fig. 4), an antifriction fluorine-containing coating is applied, which is a solution based on technical perfluoropolyether acid 6MFK-180 in a freon composition "Kh13KNNKh" with a mass fraction of a fluorine-containing substance of 2.3%.

On a press-rolling machine, in two operations, in one or several transitions, at each operation, riffles of the right, then the left direction are formed.

When forming the corrugation of the right and left directions (Fig. 3), (Fig. 4), punches 14, 20 with shaping protrusions of a trapezoidal profile are used (example 1), as well as rollers 13, 19 (Fig. 3), (Fig. 4) a trapezoidal profile with a front conical section with an angle α ₂ = 12 °, with a rear conical section with an angle β ₂ ⁼ 12 ° and with a radius of conjugation R _p = 3 m _m with a cylindrical section with a length of a ₂ = 8 _mm .

In the process of forming the corrugation on the working surfaces M, P of punches 14, 20, on the working surfaces H, C of rollers 13, 19 and on the outer surfaces O, T of blanks 12, 18 (Fig. 3), (Fig. 4), a fluorine-containing emulsion is applied lubricant - a composition of 2% perfluoropolyether acid 6MFK-180 technical in industrial oil.

The implementation of the method for manufacturing axisymmetric casings with internal grooves in accordance with the invention makes it possible to obtain casings of various standard sizes with high dimensional accuracy, with a high quality of the processed surface, with a high metal utilization rate, with high productivity and high durability of the deforming tool.

The invention can be used in the production of various standard sizes of steel axisymmetric shells with internal grooves.

The indicated positive effect is confirmed by tests on prototypes of casings manufactured according to this technical proposal.

At present, technical documentation has been developed, tests have been carried out and serial production of casings according to the proposed invention is planned.

Claims (5)

1. A method of manufacturing axisymmetric casings with internal grooves, including blank and pressure processing with the formation of spiral grooves of the opposite direction on the inner surface of the workpiece in two operations, first with a punch equipped with shaping protrusions of the right, then left direction, with the joint movement of the punch with the workpiece through the die with a calibrating hole of a larger, then a smaller diameter, characterized in that the pipe is cut into dimensional workpieces, machining is performed with the formation of a step on the inner surface of the workpiece and phosphating, then the workpiece is installed in the device until the punch stops in the workpiece ledge and riffles are formed in one or several transitions at each operation of pressure treatment by means of a punch and a matrix, while the shaping protrusions of the punch are made of a trapezoidal profile with front and rear conical sections with an angle of (25 ÷ 35) °, conjugated with a cylindrical section of length (0.1 ÷ 0.7) mm, the working surface of the matrix is made of a trapezoidal profile with front and rear conical sections with an angle (5 ÷ 15) °, conjugated along the radius (0.5 ÷ 2) mm with a cylindrical section with a length of (2 ÷ 7) mm, an antifriction fluorine-containing coating is applied to the working surfaces of the punch and matrix, and in the process of forming the grooves, a fluorine-containing lubricating emulsion based on perfluoropolyether acid and industrial oil is applied to the working surfaces of the punch and matrix and on the outer surface of the workpiece. 2. The method according to claim 1, characterized in that the formation of the right, then the left direction on the inner surface of the blanks is performed on a pressure-rolling machine by deforming rollers on a punch with shaping protrusions of the right, then the left direction. 3. The method according to claim 1, characterized in that the formation on the inner surface of the workpieces of the right, then the left direction is performed on a pressure-rolling machine with deforming rollers of a trapezoidal profile with front and rear conical sections with an angle of (10 ÷ 15) °, conjugated along radius (2 ÷ 5) mm with a cylindrical section with a length of (5 ÷ 10) mm. 4. The method according to claim 1, characterized in that a solution of technical acid 6MFK-180 with a mass fraction of a fluorine-containing substance (2.0 ÷ 2.5)% in a freon composition "Kh13KNNKh" is used as an antifriction fluorine-containing coating of the working surfaces of the deforming tool. 5. The method according to claim 1, characterized in that a fluorine-containing lubricant emulsion is applied to the working surfaces of the deforming tool and to the outer surface of the workpiece, which is a composition (0.4 ÷ 4)% of technical perfluoropolyether acid 6MFK-180 in industrial oil.

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