Spurs. Stamp for crimping tubular workpieces Stamps for crimping with workpiece supports

30. Typical designs dies for drawing parts with flange, stepped and conical shapes.

With flange:

A typical design of a drawing die with a fold holder 2, operating from the buffer of a universal press, is shown in Fig. 229, a. The transmission link between the press buffer and the fold holder is the buffer pins /. The finished part is removed from the matrix 4 at the end of the lifting of the slider through the ejector 5 and the pusher 6. If the bottom of the stamped part is flat and located perpendicular to the drawing axis, then when the die is closed, a gap z is left between the ejector 5 and the upper plate 3, i.e. work without "hard" blow.

The process of converting a sheet blank into a hollow one using a fold holder is accompanied by complex loading of the material, especially in the flange area. The flange experiences tangential compression from compressive stress a, (Fig. 229.6), which is the main deformation of the material in this zone, radial tension from tensile stress o r and

shaping.

Conical shape:

Drawing low conical parts is usually done in 1 operation, but is complicated by the fact that art. The deformation of the workpiece is small (with the exception of places adjacent to the rounded edges of the punch), as a result of which the hood “springs back” and loses its shape. Therefore, it is necessary to increase the clamping pressure and

Rice. 229. Drawing out a hollow glass with workpiece clamping

create significant tensile stresses in the deformable workpiece that exceed the elastic limit

material, through the use of a matrix with exhaust ribs (Fig. 134, a).

In Fig. 134, b shows another method of drawing shallow but wide cones (lamp reflectors), produced in a stamp with a conical clamp. Drawing of this type of parts can also be done well by hydraulic stamping. In most cases, drawing conical parts of medium depth is carried out in 1 operation. Only with a small relative thickness of the fastener, as well as in the presence of a flange, 2 or 3 drawing operations are required. When stamping parts from relatively thick material (S/D)100>2.5, s

with a small difference in diametrical dimensions, drawing can occur without clamping, similar to drawing cylindrical parts. IN in this case calibration is required at the end of the working stroke with a dull blow. In the manufacture of thin-walled conical parts, this means. by the difference in the diameters of the bottom and top, first draw out a simpler rounded shape with a surface equal to the surface finished part, and then the finished product is obtained in the calibration stamp. form. Technological calculations of transitions here are the same as when drawing cylindrical parts with a flange. mn = dn /dn-1, dn and dn-1 are the diameters of the current and previous hoods.

Stepped shape:

Of particular interest is the dual process, combining a conventional hood with an inversion hood.

Reversible drawing brings great effect when stamping step-shaped parts. A typical example is a multi-pass stamping process deep details type of headlights for cars. First, a cylinder or hemisphere is pulled out, and then the workpiece is pulled in the opposite direction (inverted) to obtain the desired shape of the product.

Schemes of reversible (reversible) hood

31. Typical designs of dies for flanging.

Flanging dies can be divided into two groups: dies without clamping the workpiece and stamps with clamping the workpiece. Dies without clamping the workpiece are used only when beading large products, where there is no fear of the workpiece being overstretched during beading. Full clamping of the workpiece can usually be achieved by using flanging dies of the second group with strong pressure.

In Fig. 207, and a flanging stamp is presented with a lower clamp, operating from a rubber buffer 1 placed under the stamp, which transmits pressure through the washer 2 and rods 3 to the pressure plate 5. When lowering the upper part of the stamp, the workpiece 6, laid on the plate 5 so that the flanging punch 4 with its upper protrusion enters the preliminary hole, is first clamped by matrix 7, and then beaded. Ejecting the product from the top of the die after flanging can be done using a conventional rigid ejector (rod) operating from the press itself, or, as shown in the figure, using springs 9 and ejector 8.

When flanging larger products, instead of a rubber buffer or spring, it is better to use pneumatic or hydropneumatic devices.

In Fig. 207, b shows a similar stamp with an upper clamp for flanging a hole in the tractor clutch. Here, the product 4 is pressed when the upper part of the die is lowered by the plate 3, which is under the action of sixteen springs 2 located in a circle around the flanging punch 1.

Pressing the annular part of the material from below during the flanging process and subsequent ejection of the product from the matrix 5 after flanging is carried out by the ejector 6, which receives movement through the rods 7 from the lower pneumatic cushion of the press.

32. Typical designs of stamps for distribution.

The design of the dispensing die depends on the required degree of deformation, which

characterized by the distribution coefficient Krazd. If Krazd > Krazd. limit . , when local loss of stability is excluded, then a simple open stamp with a conical punch is used

(for free distribution) and a lower cylindrical clamp along internal diameter pipe blank, which is fixed to the bottom plate of the die.

With more high degrees deformations, deformations

when Krazd< Кразд.прел . применяют штампы со скользящим внешним подпором (рис. 1).

Fig. 1. Dies for distributing the ends of tubular blanks with sliding external support.

The stamp consists of an upper plate 1 and a conical punch 2 and rod pushers 3 attached to it. A cylindrical support mandrel 5 is fixed to the lower plate 7, the diameter of which D is equal to the outer diameter of the pipe blank. A support sleeve 4 moves along the mandrel, supported by springs 6. When the sleeve is in the upper position (shown in the figure with a dashed line), the workpiece is installed on the shoulder of the mandrel 5, and the workpiece protrudes from the sleeve by

(0.2-0.3) D.

When the top of the die is lowered, the conical punch enters the workpiece and begins to push it out.

At the same time, pushers 3 press on the support sleeve 4 (compressing the springs 6) and move it down along the mandrel, thereby allowing the punch to completely dispense the pipe blank until

required sizes. During the reverse stroke, spring 6 lifts sleeve 4 up along with the stamped part.

The operation is mainly designed to increase the diameter of a cylindrical workpiece for

pipe joining. The optimal distribution angle is 10300.

If the diameter of the original hollow cylinder is d0, then largest diameter d1, up to which distribution can be carried out (Fig. 3).

d1 ,=Ksection * d0, where Ksection is the expansion coefficient depending on the relative thickness

blanks. s/d0 =0.04 Ksection =1.46 s/d0 =0.14 Ksection =1.68. The thickness of the material decreases during distribution. The smallest thickness at the point of greatest stretch is determined by

formula. s1 = s √ 1/ Ksection

Dispensing can be carried out on the edges of a hollow workpiece or on its middle part in dies with split dies, elastic media and other methods.

The dimensions of the workpiece for distribution are determined based on the equality of the volumes of the workpiece and the part without taking into account changes in the thickness of the metal.

Fig. 3. a - elastic punch. b- in detachable matrices.

33. Typical designs of crimping dies.

Crimping dies are divided into two groups : dies for free crimping and dies with workpiece supports. Stamps of the first group They have only guide devices for a tubular or hollow workpiece, without internal or external supports, as a result of which loss of stability during crimping is possible. To prevent loss of stability, the workpiece in one operation receives a shape change in which the required crimping force will be less than the critical one.

Rice. 1. Schemes of dies for free crimping of ends - parts.

In Fig. Figure 1 shows two diagrams of free crimping dies: on the first stamp, the end of pipe 3 (Fig. 1, a) is crimped in a stationary die, and on the second stamp, the neck is crimped

on a hollow product 3 (Fig. 1, b) is carried out by a movable matrix 1, fixed on the upper plate of the die using a matrix holder 5. To fix the workpiece, there is a cylindrical belt either on the matrix /, or on the plate 4. Removal of parts is carried out by ejector 2, powered by lower or from the upper buffer. The length of the compressed part is set by changing the stroke of the press.

In Fig. 2, a shows a diagram of a die with external support; in him

the part of the workpiece that is not subjected to crimping is covered by an outer ring 2, which prevents loss of stability and bulging of the workpiece outward. Due to this, such dies can produce a greater degree of deformation than in dies without supports. To facilitate installation of workpieces and removal of crimped parts from holder 2, it is made detachable; in the non-working state, it is unclenched by springs 1. The clamp is closed around the workpiece by moving the upper part of the die downwards with wedges 4. To remove the compressed part from the matrix 5, the die is equipped with an ejector 3, operating from a spring 6 or from a crossbar in the press slide.

There are also dies with a sliding outer ring that supports the workpiece along its entire undeformed part.

In Fig. 2, b and c show dies for crimping the end part of a pipe or hollow workpiece into a sphere, equipped with external (Fig. 2, c) or external and internal (Fig. 2, b) supports for the workpiece.

Rice. 2. Diagrams of dies for crimping the ends of parts with supports These dies allow you to make significant shape changes in one operation,

due to which the number of operations during multi-operation stamping is reduced. In a stamp intended for crimping the end part of a pipe (Fig. 2, b), the pipe blank is installed in the gap between the outer sliding race 2 and the internal rod base 3, on which there is a step to support the end of the blank. An insert is pressed into the hole of the rod 3, which has a spherical head along which the workpiece is crimped. In the stamp for crimping a hollow workpiece (Fig. 2, c), liner 6 is missing. The workpiece is installed along the holder 2 and the base rod 3.

When the press slide moves downwards, matrix 1 moves the sliding cage 2 downwards and compresses the workpiece along the sphere. The clip operates from the lower buffer through rods 4, sliding in the lower plate 5. The part is pushed out when the press moves upward with the insert 6, also connected to the lower buffer.

The operation is widely used for the production of cartridge cases. The optimal taper angle is 15-200. Feature of stamps There is a need to ensure the stability of the workpiece during the crimping process. Dies are divided into: 1. without workpiece support 2. with workpiece support. Without support it is rarely used and for relatively thick-walled workpieces.

Possibility of crimping cylindrical workpieces in one operation orped coefficient. crimping

d ,=Kobzh * D, where Kdiv is the distribution coefficient depending on design features stamp and type of material. Table 5.

Kobzh also depends on the relative thickness of the material. For mild steel (α=200).- s/D=0.02 Kobzh

0.8; s/D=0.12 Kobzh =0.65.

As the taper angle decreases, the value of Kobj decreases. The wall thickness at the crimp site increases due to compression of the metal. The greatest thickness at the point of greatest compression is determined by the formula.

s1 = s √ 1/ Kobzh

34. Design of dies with working elements made of hard alloy.

TV The alloy is ceramic (not metal) carbide W. Tv. alloys have an increased tendency to fracture, therefore only if special design and technological requirements are met is it possible reliable operation dies with working elements made of hard alloys, the so-called hard alloy dies, and increasing their durability by tens and hundreds of times compared to dies with steel working elements. Modern designs carbide dies should provide increased rigidity compared to steel, more accurate and reliable direction of the upper part of the die in relation to the bottom, maximum proximity of the shank axis to the center of pressure of the die, durability and reliability of removal units and elastic elements, increased wear resistance of the guide strips, possibly larger number regrinding and lack of stress concentration on the carbide.

Increased rigidity and strength of the slabs is achieved by increasing their thickness. For matrices with a plan size of 350x200 mm, the recommended thickness of the bottom plate is 100-120 mm. The bottom and top plates and the stack plate are made of 45 steel. These plates are heat treated to a hardness of 30-35 HRC. The deviation from the flatness of the matrix base and the adjacent surface of the lower die plate, as well as the rear part of the punches with the punch holder and the adjacent surface of the upper plate (or intermediate backing plate) should not exceed 0.005 mm. Failure to comply with this requirement can reduce the durability of the stamp several times.

Carbide die screws are made from 45 steel and then heat treated. It should be taken into account that even slight stretching of the screws leads to a decrease in the durability of carbide dies.

A more accurate and reliable direction of the upper part of the carbide die in relation to the lower part, compared to steel, is achieved by using rolling guides (at least 4). The recommended tension in ball guides is 0.01-0.015 mm. In some cases, an interference of 0.02, -0.03 mm is used. An increase in tension leads to a decrease in the durability of the guides. However, it is advisable to increase the tension when cutting thin material up to 0.5 mm thick or when working on worn-out pressing equipment. The durability of rolling guides is 10-16 million operating cycles, depending on the amount of tension. Columns and bushings are made of steel ШХ15. After heat treatment Their hardness is 59-63 HRCе. Roller guides are used when cutting material up to 1.5 mm thick.

Elimination of stress concentration in the hard alloy is achieved by rounding the corners in the die windows with a radius of 0.2-0.3 mm (with the exception of the working angle in the die step knife window sequential action) and determining the thickness of the matrix, the minimum width of its wall and the distance between the working windows based on appropriate calculations.

Ensuring the durability and reliability of strip removal elements and strip guidance is achieved by reinforcing strippers with hardened steel plates and carbide elements, using carbide guide rods and release agents for strip direction and lifting, and using new stripper designs. The most common are two types of peelers: those that provide the direction of the strip as it moves over the matrix (Fig. 1 a) and those that do not provide it (Fig. 1, b). The use of the latter requires the presence of separate elements in the stamp to guide the strip.

In most cases, moving pullers are performed on rolling guides. The guides have the greatest rigidity if the columns are rigidly fixed to the puller (Fig. 2). To avoid distortions resulting from the presence of burrs on the tape, the puller is not pressed against the tape; the gap between it and the composition-sheet tape is 0.5-0.8 mm (Fig. 3).

When cutting parts from material with a thickness of over 0.5 mm, as a rule,

stamps with fixed puller The parts cut out in these dies are slightly inferior in flatness to those obtained in dies with a movable stripper, since the cutting occurs with sharp working edges of the punches and dies. Increasing the rigidity of the punches is achieved by reducing their length to the minimum permissible and using stepped punches. It is necessary that the punch is securely fastened in the punch holder. As a rule, the thickness of the punch holder should be at least 1/3 of the height of the punch.

Designs of working parts of dies. The designs of carbide dies largely depend on the methods of manufacturing the main form-building parts, in particular matrices. The two most common methods for processing matrices are diamond grinding and

The dimensions of pipe parts are checked after each technological operation. Tolerances for dimensional deviations are specified in drawings and technical specifications for the supply of parts.

After the operation, the length of the workpiece or part is checked with a normal measuring instrument: ruler, tape measure, caliper, etc.

Control of the shaped cut of pipe ends can be performed using end or solid templates that are placed on the pipe, similar to contour trim templates (SHOK).

If there are increased requirements for the quality of the shaped pipe cut, special plazas are made for inspection.

SEALING PIPE ENDS

Flaring

Flaring of pipe ends is the most commonly used operation in the manufacture of detachable nipple connections for pipelines of aircraft hydraulic and oil systems. Flaring of pipes with a diameter of up to 20 mm and a wall thickness of up to 1 mm can be done manually using a cone mandrel in two ways. To do this, the end of the pipe is clamped in a device pos.2 , consisting of two halves with a socket along the outer diameter of the pipe and a conical part in the shape of a flaring and a mandrel pos.1 apply several blows with a hammer or rotate the mandrel manually pos.3 until the required cone dimensions are obtained.

Flaring of pipes with a diameter of up to 20 mm and a wall thickness of up to 1 mm can be done manually using a cone mandrel in two ways. To do this, the end of the pipe is clamped in a device 2 , consisting of two halves with a socket along the outer diameter of the pipe and a conical part in the shape of a flaring and a mandrel 1 Apply several blows with a hammer or rotate the mandrel manually until the required cone dimensions are obtained. However, when flaring using these methods, it is difficult to obtain the required correctness and cleanliness of the inner conical surface. These qualities are especially important for nipple connections, in which tightness is created without additional seals. In addition, these methods are ineffective. Therefore, it is more rational to flare the ends of the pipes on special pipe-flaring machines. The essence of the process of flaring pipe ends on a machine is to obtain a conical

The socket is socketed by a concentrated force from inside the pipe using a rotating tool.

When flaring, the original pipe wall thickness decreases S 0 before S 1 . The wall thickness at the flaring edge can be calculated using the formula

Where S 1 --- thickness walls at the end of the bell;

S 0--- pipe wall thickness in the cylindrical part;

D0 ---outer pipe diameter before flaring;

D 1--- outside diameter pipes after flaring. Flaring of short pipes is carried out using flaring dies.

Crimping of pipe ends

Pipes with crimped ends are used in the design of rigid aircraft control rods. The crimping process diagram is shown below.

Under the influence of compressive forces R there is a decrease in diameter with D0 before d, thickening of the wall with S 0 before S 1 and pipe extension with L 0 before L 1 .

There are two ways to crimp the ends of pipes. First way. Crimping by pushing the pipe into a ring die. The diagram of a pipe crimping die is shown above. Blank part (pipe) pos. 2 with diameter D0 placed in a matrix, position 3, which has a conical entry and calibrating part with a diameter d. During the working stroke of the press slide, the punch position 1 fixes the pipe along the outer diameter and pushes its lower part into the matrix, compressing the end of the pipe to the diameter d.

The limit for reducing the diameter of the original pipe is determined by the loss of stability (longitudinal bending) of the wall of the uncompressed part and the plasticity of the material. Buckling occurs when the stress in the material reaches its yield point. The stability of the pipe wall is affected by the ratio of pipe thickness to outer diameter S 0 / D0.

Maximum degree pipe crimping is determined by the limiting value of the crimping ratio Kobzh, .

For increase Kobzh a pipe wall support is used between the matrix and the punch, preventing loss of stability.

Good results are obtained by local heating of the end of the pipe, which reduces the yield strength of the material in the deformed part. Due to the decrease in pressure on the pipes, loss of stability occurs much later. This method is especially effective when crimping pipes from aluminum alloys. Due to the high thermal conductivity of these alloys, it is not the pipe that is heated, but the matrix; the pipe heats up from contact with the matrix.

Second way. Crimping in split dies.

Using the first method, it is not advisable to crimp long pipes, since presses with a large closed height, large dies and special clamps are needed to protect the pipe from longitudinal bending. The method of crimping the ends of especially long pipes using split dies is more widespread. A diagram of the process is shown.

Scheme of the process of crimping the ends of pipes with split dies. Pos. 1 and 3 - upper and lower die strikers, pos. 2 - pipe, pos. 3 - calibrating mandrel.

Upper and lower strikers pos. 1 And 4 The stamps have a working part machined in a closed state and corresponding to the shape of the compressed part of the pipe. The strikers make a frequent back-and-forth movement (vibrate), squeezing the end of the pipe pos.2. The pipe is gradually fed into the stamp until the required length of the compressed part is obtained.

In cases where it is necessary to obtain the exact internal diameter of the compressed part of the pipe, a calibrating mandrel is inserted inside pos.3 and feed it into the stamp along with the pipe. After the process is completed, the mandrel is removed from the pipe. The advantages of the process of crimping pipe ends in a vibrating split die are as follows:

a) more are created favorable conditions for plastic deformation than with ring die crimping;

b) the axial force of the pipe into the die Q is significantly less than in the first method;

c) the number of transitions decreases;

d) a mandrel can be used, which makes it possible to obtain a calibrated internal diameter of the pipe without subsequent machining.

The invention relates to metal forming and can be used for the manufacture of parts from tubular blanks. The stamp contains a matrix, a punch, a clamp, an upper and lower holder. The upper frame is made with work surface, the inner diameter of which is equal to the outer diameter of the tubular workpiece. The stamp contains an insert made of ductile metal with a diameter equal to the inner diameter of the tubular workpiece. The lower cage is made with a non-working cavity, the diameter of which is equal to diameter liner made of ductile metal, and the height is equal to the length of the tubular workpiece. A die with a calibrated hole is placed between the upper and lower frames. In this case, the insert made of ductile metal together with the die is made with the possibility of turning them over. Increases productivity by reusing the liner. 1 salary f-ly, 2 ill.

Drawings for RF patent 2277027

The invention relates to metal forming and can be used for the manufacture of parts from tubular blanks.

A known stamp for the manufacture of parts from tubular blanks (copyright certificate SU No. 797820, MKI B 21 D 22/02, 1981), containing an insert, a matrix, a punch and a guide sleeve. The disadvantage of the known stamp is the structural complexity of the composite punch and the complexity of removing the compressed workpiece from the matrix cavity.

The closest to the proposed stamp in technical essence and purpose is the drawing stamp (author's certificate SU No. 863075, MKI B 21 D 22/02, 1980). The stamp contains a punch, a matrix with a working cavity filled with ductile metal, a clamp and a bushing with a non-working cavity and a calibrated hole, located in the working cavity of the matrix. In this case, the calibrated hole of the sleeve communicates with the cavity of the matrix. The disadvantage of the known stamp is that after shaping the product on this stamp, it is necessary to carry out an operation to separate and remove ductile metal from the sleeve, which requires readjustment of the stamp during the working process.

The objective of the invention is to increase the productivity of the stamp without compromising quality finished products due to the possibility of reusing a ductile metal insert without an additional operation to separate and remove it from the die cavity and readjust it during the working process.

To solve this problem, the stamp containing a matrix, a punch and a clamp, unlike the prototype, is equipped with upper and lower clips. The upper cage is made with a working cavity, the inner diameter of which is equal to the outer diameter of the tubular workpiece D, in which an insert made of ductile metal with a diameter equal to the inner diameter d of the workpiece is placed. The lower cage is made with a non-working cavity, the diameter of which is equal to the diameter d of the ductile metal liner, and linear dimension the height is equal to the length L of the tubular workpiece. Due to the effect of force on a liner made of ductile metal (for example, lead), radial back pressure is provided, which prevents the formation of circular waves (corrugations) on the tubular workpiece and thickening of the walls both in the forming zone and in the support zone. Between the upper and lower races there is a die with a calibrated hole. The ductile metal insert and the die are made with the possibility of jointly turning them 180° in the axial direction. After turning over the liner together with the die, the process resumes without additional preparatory work. In addition, the design provides for replaceable dies with excellent calibrated hole parameters. Due to this, it is possible to regulate the amount of back pressure inside the tubular workpiece.

The invention is illustrated by graphic materials, where figure 1 shows a stamp for making parts from tubular blanks before starting work; in Fig. 2 - the same after the end of crimping.

The proposed stamp contains a matrix 1, a punch 2, an upper cage 3, the internal diameter of which is equal to outer diameter D of a tubular workpiece 4. An insert 5 made of ductile metal (for example, lead) with a diameter d equal to the inner diameter of the workpiece being processed is installed in the workpiece 4. The stamp also contains a lower race 6, a die 7 and a clamp 8. The diameter of the non-working cavity of the bottom race 6 is equal to the diameter d of the ductile metal insert, and the linear dimension in height is equal to the length of the tubular workpiece L.

The stamp works in the following way. An insert made of plastic metal 5 with a die 7 is inserted into the lower cage 6, a workpiece 4 and an upper cage 3 are installed, and then a punch 2 and a matrix 1. During the working stroke of the matrix 1 and punch 2, the plastic metal insert 5 is squeezed out through a calibrated hole in the die 7 into the cavity of the lower cage 6, while the upper part of the tubular workpiece 4 is pushed into the working cavity formed between the matrix 1 and the punch 2, resulting in the compression of the tubular workpiece. After completing the crimping of the tubular workpiece, the clamp 8 returns the upper clip 3 to its original position. After receiving and removing the finished part to repeat the process of crimping tubular blanks, the insert 5 made of ductile metal together with the die 7 is removed from the lower holder, turned over 180° and reinstalled in the die, a new tubular blank is inserted, and the crimping process is repeated. If it is necessary to change the amount of back pressure, which affects the quality of shaping of the crimped tubular workpiece, it is enough to replace the die with a different calibrated hole parameter.

The use of the proposed invention makes it possible to form parts without additional readjustment of the die. The ability to use replaceable dies with different calibrated holes allows you to change the amount of back pressure in the die and obtain parts with a given distributed wall thickness, obtained from tubular blanks with different geometric and mechanical parameters.

CLAIM

1. A stamp for crimping tubular blanks, containing a matrix, a punch and a clamp, characterized in that it is equipped with upper and lower races, the upper race is made with a working surface, the internal diameter of which is equal to the outer diameter of the tubular blank, and an insert made of plastic metal with a diameter equal to the inner diameter of the tubular blank, the lower race is made with a non-working cavity, the diameter of which is equal to the diameter of the plastic metal liner, and the linear dimension is equal to the length of the tubular blank, a die with a calibrated hole located between the upper and lower races, while the plastic metal liner together with the die is made with the possibility of turning them over.

2. The stamp according to claim 1, characterized in that the die is replaceable, with different diameters calibrated hole.

The utility model relates to metal forming, in particular to stamping of parts with elastic media from tubular blanks. The stamp contains a matrix consisting of an upper and lower parts, punch, elastic medium. The matrix is ​​located in a container and a tubular blank with an elastic medium placed in it is installed in it, in the lower and upper parts The matrix has a hole of variable diameter, which ensures crimping of the end sections of the tubular workpiece and distribution of its middle part. The technical result consists in increasing the technological capabilities of the operation of stamping parts from tubular blanks due to the simultaneous performance of crimping and distribution of the tubular blank.

The utility model relates to metal forming, in particular to stamping of parts with elastic media from tubular blanks.

A device for distributing pipes is known (Use of polyurethane in sheet metal stamping production / V.A. Khodyrev - Perm: 1993. - p. 218, see p. 125), consisting of a split matrix and a punch. The matrix contains a tubular blank, inside of which an elastic medium is placed. This device makes it possible to produce parts from pipes by dispensing a tubular blank with elastic media over a rigid matrix.

The disadvantage of this device is its low technological capabilities. The device allows only pipe expansion, which manifests itself in an increase in the cross-sectional size of the tubular blank, determined by the limiting coefficient of forming.

The objective of the claimed utility model is to increase the technological capabilities of the operation of stamping parts from tubular blanks. The technical result achieved by the claimed utility model is to increase the technological capabilities of the operation of stamping parts from tubular blanks due to the simultaneous performance of crimping and distribution of the tubular blank.

This is achieved by the fact that in the stamp for distributing and crimping a tubular billet, containing a matrix consisting of upper and lower parts, a punch, an elastic medium, in the lower and upper parts of the matrix there is a hole of variable diameter, which ensures crimping of the end sections of the tubular billet and distribution of its middle parts.

What is new in the claimed device is that the matrix is ​​located in a container and in the lower and upper parts of the matrix there is a hole of variable diameter, which ensures crimping of the end sections of the tubular workpiece and distribution of its middle part.

Due to the fact that the matrix, consisting of upper and lower parts, is located in the container, reliable movement of the upper part of the matrix is ​​ensured, because the container serves as a guide for it. Due to the fact that in the lower and upper parts of the matrix there is a hole of variable diameter, which ensures the compression of the end sections of the tubular workpiece and the distribution of its middle part, in combination with other features, simultaneous compression of the ends of the tubular workpiece and the distribution of its middle part are ensured. Due to the fact that in parts of the matrix there is a hole of variable diameter so that in those places of the matrix where the end sections of the tubular workpiece are installed, the diameter of the hole is made smaller than the diameter of the pipe workpiece, this will ensure compression of the end sections of the workpiece. Due to the fact that the diameter of the hole is variable, namely, it is made larger than the diameter of the tubular blank in those parts of the matrix where the middle part of the tubular blank will be, it is possible to distribute its middle part. In addition, making holes in parts of the matrix with variable diameter, i.e. from diameter, smaller diameter pipe billet, up to a diameter larger than the diameter of the pipe billet, provides vertical installation pipe blank in the matrix.

The design of the die allows for simultaneous crimping of the end sections of the pipe blank and distribution of its middle part.

The applicant is not aware of objects with this set of essential features, therefore, the claimed technical solution has novelty.

The utility model is illustrated graphically. The figure shows a stamp for distributing and crimping a tubular blank.

The stamp includes a lower part 1 of the matrix, a container 2. A tubular blank 3 is installed vertically on the lower part 1 of the matrix. The stamp also includes an upper part 4 of the matrix, an elastic medium 5, for example, polyurethane granules. The finished part 6 is obtained from the workpiece 3. The elastic medium 5 is located in the tubular workpiece 3 and in the hole 8 of variable diameter in the upper part 4 of the matrix and in the hole 7 of variable diameter in the lower part 1 of the matrix; the die also includes a punch 9.

The stamp works as follows: the lower part 1 of the matrix is ​​installed in the container 2, a tubular blank 3 is vertically inserted inside the lower part of the matrix, and the upper part 4 of the matrix is ​​installed on top. The elastic medium 5 is poured into the hole 8 in the upper part 4 of the matrix into the tubular workpiece 3 and into the hole 7 in the lower part 1 of the matrix. By moving the press slide (not shown in the figure) with force P, the punch 9 moves, which causes the upper part 4 of the matrix to move, which leads to the movement of the tubular workpiece 3 into the hole 8 of variable diameter in the upper part 4 of the matrix and to the movement of the tubular workpiece 3 into hole 7 of variable diameter in the lower part 1 of the matrix, which leads to compression of the end sections of the tubular workpiece 3. Force P is also transmitted to the elastic medium 5, through which in turn it is transmitted to the walls of the tubular workpiece 3, which leads to the distribution of its middle part. After the press slide and punch 9 reach the maximum upper position, the finished part 6 and the elastic medium 5 are removed in the reverse order.

A stamp for distributing and crimping a tubular workpiece, containing a matrix consisting of upper and lower parts, a punch, an elastic medium, characterized in that the matrix is ​​located in a container and is made with holes of variable diameter in the lower and upper parts to allow crimping of the end sections of the tubular workpiece and simultaneous distribution of its middle part.

In the manufacture and installation of pipelines, various tee connections are widely used (Fig. 9), which are designed to produce pipe branches - equal-bore (without changing the diameter of the branch) and transitional (with changing the diameter of the branch).

Rice. 9. Designs of equal bore and transition tee connections and tees for process pipelines:

a - mortise connection without reinforcing elements, b- tap-in connection with reinforced fitting, V- connection by insertion with a reinforcing saddle, G- welded tee, d- forged tee, e- tee stamped from pipes

The variety of designs of tee joints is caused, firstly, by the fact that the pipeline in the places where the branches adjoin it is weakened by cutting holes and, depending on the safety factor of the pipeline, it is required to be strengthened to varying degrees in these places; secondly, the difference in their manufacturing technology. Of the types of welded tee connections, the most economical in terms of the labor intensity of their production and metal consumption is the “tie-in”, i.e., a welded branch without reinforcement (reinforcing elements). The tap-in connection without reinforcement is widely used for pipelines on conditional pressure up to 25 kgf/cm2. For pipelines with nominal pressure from 40 kgf/cm 2 and higher in terms of strength, this connection without reinforcement is used only for transition connections of small diameter pipes. Such connections are strengthened by using a thickened pipe or fitting, as well as linings and saddles.

Unlike welded tee joints, stamped tees have high strength due to the seamless smooth connection of the neck with the body. This allows the use of these tees with walls of thickness equal to the wall thickness of the connected pipes.

Stamped tees are made of carbon steel with a nominal bore from 50 to 400 mm for nominal pressure up to 100 kgf/cm2.

In factory conditions, seamless tees are made by hot stamping from pipes on crank and hydraulic presses in multi-strand dies in two, three or four operations, depending on the ratio of the diameters of the body and neck of the tee and the thickness of their walls. The basis of the technology for manufacturing stamped tees is the combined process of crimping a blank pipe in diameter with simultaneous extrusion of part of the volume of metal into the neck (Fig. 10, a) and calibration (Fig. 10, b). In Fig. 10 c, d, stamped tees are shown.

Transitions are used to change the diameter of the pipeline. According to the manufacturing method, transitions are divided into stamped, welded flap, and welded rolled. The transition connection can be obtained by directly crimping the end of the pipe to a smaller diameter.

Based on their shape, transitions are distinguished between concentric and eccentric. Concentric transitions are installed mainly in vertical pipelines, and eccentric ones - in horizontal ones.

Steel concentric and eccentric stamped transitions are made of carbon steel 20 for nominal pressure up to 100 kgf/cm 2 With conditional passages from 50×40 to 400×350 mm.

Stamped transitions have a short length, a smooth inner surface and high accuracy connecting dimensions.

Welded petal transitions are manufactured for nominal pressure up to 40 kgf/cm 2 with nominal diameters from 150×80 to 400×350 mm.

Welded rolled transitions are manufactured for nominal pressure up to 40 kgf/cm 2 with nominal diameters from 150×80 to 1600×1400 mm.

The main methods of serial factory production of stamped transitions are distributing the blank pipe by diameter in a hot state and crimping it with external support in a cold state.

Rice. 10. Die diagram for making tees from pipes: A- stamp for crimping and preliminary drawing of the neck of the tee, 6 - stamp for calibrating the body and neck of the tee, 3 - design of a seamless tee of a cylindrical shape, and - design of a seamless tee of a spherical-conical shape; 1 - punch, 2 - crossbar, 3 - upper matrix,
4 - handle, 5 - swivel support, 6 - lower matrix, 7 - ejector, 8 - mandrel,
9 - puller

Rice. 11. Diagram of dies for making transitions by crimping with external support:

A- concentric, b - eccentric; 1 - blank pipe after stamping.
2 - retaining ring, 3 - punch, 4 - matrix, 5 - ejector

Distribution of the pipe blank in a hot state is carried out during the manufacture of transitions with a diameter ratio of up to 1.7. Stamping is carried out by distributing one end of a heated pipe blank using a conical punch inserted into the blank by press force.

Crimping blank pipes with external support makes it possible to produce transitions with a diameter ratio of up to 2.1. Crimping is carried out along the diameter in a conical matrix 4 (Fig. 11) one end of the blank pipe. To avoid bulging of the workpiece wall, use a retaining ring 2 (block container, more details here http://www.uralincom.ru), covering the workpiece from the outside.

Rice. 12. Plugs for process pipelines: A- spherical, b - flat, V- flat ribbed, G- flanged

Rice. 13. Diagram of a stamp for drawing out plugs:

1 - punch, 2 - matrix, 3 - puller, 4- puller spring, 5 - rack, 6 - stamped plug

Transitions are stamped in single-strand dies on hydraulic and friction presses.

Steel plugs (Fig. 12) are used to close the free ends of pipelines. According to their design, they are divided into welded spherical (Fig. 12, A), flat (Fig. 12.6), flat ribbed (Fig. 12 V) and flanged (Fig. 12,d). ""

Spherical steel plugs are used for nominal pressures up to 100 kgf/cm 2 and with nominal diameter from 40 to 250 mm as well as with a nominal diameter from 300 to 1600 mm. They are made from sheet steel grades MStZ and steel 20 and 10G2. The convex part of the plugs has an elliptical shape, which ensures their high strength with low weight.

The plugs are pressed by drawing without thinning the walls in single-strand dies (Fig. 13) on friction and hydraulic presses in cold and hot conditions.

Flat plugs are used for nominal pressures up to 25 kgf/cm 2 and are manufactured with a nominal bore from 40 to 600 mm.

Flat ribbed plugs (bottoms) are used for nominal pressure up to 25 kgf/cm 2 and are manufactured with a nominal bore from 400 to 600 mm. Rib-reinforced plugs are more economical than flat plugs.