RU2632726C1 - Method of manufacturing shell circuit of protection casing - Google Patents

Abstract

FIELD: weapon and ammunition.

SUBSTANCE: on the inner surface of the tubular blank with the bottom forming multi-spiral scrolls of the opposite direction, forming a grid of protuberances of a rhombic shape. The formation is carried out in two successive operations of reducing the broach. The first operation is performed using a central spindle with instrumental spiral projections having an inclination angle of 32-33°. In the second operation, a central rod is used with an angle of inclination of the instrumental spiral projections of 30-31°. The processed tubular blank is removed by unscrewing the central rod from it when the workpiece is braked on the ring stripper. The puller is made in the form of radially movable half rings. The diameter of the rings when closing is less than the outer diameter of the processed billet. The puller is placed under the die.

EFFECT: increasing the accuracy of the products received.

2 cl, 6 dwg

Description

 The invention relates to the processing of metals by pressure and can be used in the manufacture of fragmentation shells of ammunition for the formation on the inner surface of the blank tubular blanks of multiple helical riffles of the opposite direction, forming semi-finished striking elements in the form of rhombic protrusions.

The level of this technical field characterizes the method of manufacturing a shell of fragmentation ammunition described in patent RU 2171445 C1, F42B 12/24, B21K 21/06, B21C 37/20, 2001, which includes sequentially the operations of processing the shell metal by cold pressing by two dies of different diameters with reduction of the tubular workpiece, which is sequentially mounted on evenly spaced spiral protrusions of the central tool rod, having the opposite direction, while the piece tubular billet the taste of the casing is supplied to the dies without axial movement relative to the spiral protrusions of the tool, with the formation of a guaranteed gap between the inner surface of the casing and the central tool rod.

The corrugations are formed with a depth of 0.25-0.45 of the wall thickness of the tubular billet, according to the theory and practice of crushing shell shells when undermining equipment.

The length of the tool is obviously greater than the through tubular workpiece.

The angle of inclination of the spiral protrusions of the tool rod relative to the longitudinal axis and, therefore, of the formed grooves is optimized at 30 °, which is obviously less than the dry sliding angle, which ensures self-braking of the processed tubular semi-finished product, which is adjacent to the ring puller mounted in rotary bearings with the possibility of rotation. In this interaction, a lead screw is formed, the nut of which (shell) is screwed from the spiral protrusions of the translationally displaced central shaft.

The processed semi-finished product, free from power and geometric short circuit, is automatically removed from the stamping equipment under the influence of gravitational forces.

The disadvantages of the described method are as follows.

Suitability for the formation of multi-helical spiral grooves in products without a bottom with a length of not more than three diameters, which limits the technological capabilities of the application for the manufacture of fragmentation munitions.

With an increase in the length of the processed tubular workpiece, the forces of its removal from the punch sharply increase (pressing out), as a result of which there is a dynamic wear of the forming spiral protrusions of the tool, their thinning and chipping. The punch sticks in the shell to be treated, as a result of which it breaks when removed as a harder element of the friction pair, according to the laws of tribotechnology.

The noted disadvantages are eliminated in the method of forming multi-starting corrugations for forming on the inner surface of tubular blanks with the bottom of multi-way corrugations of the opposite direction according to patent RU 2316403 C2, B21C 37/20, B21J 5/12, B21K 21/06, 2008, which is by technical nature and the number of matching essential features is the closest analogue to the proposed method.

The known method includes two consecutive reduction operations. In each operation, a joint punching through the calibration matrix of the workpiece and punch with spiral protrusions is carried out, and each reduction operation is carried out in at least two transitions.

A feature of the reduction is that the punches are much shorter than the length of the workpiece being processed, which are pressed together at the first transition with the punch resting on the bottom of the workpiece, excluding their relative radial displacement.

At each reduction operation between the transitions, the punch is unscrewed from the workpiece along the formed spiral grooves until the relationship belt is preserved, which is used in the next reduction transition to stop the punch and ensure the direction of the spiral grooves formed at this transition.

The order of the reduction operations and the mode of transitions using a short tool allows you to discretely, sequentially form a smooth profile of multi-helical spiral grooves (corrugations) in tubular blanks with a bottom due to the stepwise reciprocating movement of the punch along the workpiece with an emphasis on the guiding technological belt of the screw relationship with the formed profile , which is provided at the previous transition reduction.

The geometric closure of the tool with the sheath to be processed at all intermediate transitions of the reduction operation of the full profile of spiral riffles serves as an emphasis for the sequential force forcing through the calibration matrix, prevents their relative rotation when the metal flows over the machined tubular blank.

The formation of semi-finished rhombic fragments on the inner surface of the tubular blank shell of the munition shell using a short tool, the length of which is several times shorter than the length of the workpiece, made it possible to distribute and significantly reduce the force of extrusion of the finished shell with a punch adequate to the number of transitions of the sequential formation of a complete profile of spiral grooves.

Incomplete unscrewing of the punch from the processed prefabricated shell at intermediate transitions of reduction ensures their kinematic closure, screw connection by means of a technological belt acting as an intermediate stop for the tool during successive joint movement through the gauge matrix. This helical girdle is the basis for the stepless and gapless direction of the spirals of the formed grooves at subsequent transitions of reduction.

The choice of the angle of inclination of the multi-helical riffles formed in the shell, which is known to be smaller than the dry sliding friction angle, makes it possible to unscrew the rotating punch from it (the spindle nuts) by self-braking the machined tubular workpiece against the ring puller.

A continuation of the noted advantages of the known method are the inherent disadvantages:

- multi-junction technology, increasing the production cycle of mass production, and additional capital costs, which increases the consumer value of products;

- high consumption of expensive stamping tools with precision accuracy.

The technical problem to which the present invention is directed is the formation of spiral corrugations on the inner surface of a blank tubular blank in one reduction pass in each direction, while increasing the profile accuracy of semi-finished striking elements.

The required technical result is achieved by the fact that in the known method of manufacturing a fragmentation shell of the shell of the shell, comprising forming on the inner surface of the tubular billet with the bottom of multi-helical riffles of the opposite direction, forming a network of rhombic protrusions, for two successive reduction operations that are carried out by pulling the tubular billet installed on a central shaft with uniformly distributed instrumental spiral projections with a stop mentioned the core in the bottom of the tubular workpiece, through matrices of different diameters by feeding the central rod with a pusher, while the treated tubular workpiece is removed from the central rod by reversing it when braking the processed workpiece on the ring puller, according to the invention, the first reduction operation is carried out using a central rod with instrumental spiral protrusions whose inclination angle is 32-33 °, and in the second reduction operation, a central rod with an inclination angle is used and structural spiral projections, comprising 30-31 °, while the machined tubular workpiece is removed by unscrewing the central rod from it by rotating it in reverse relative to the pusher in the direction opposite to the direction of the tool spiral projections, when braking the processed workpiece on the ring puller in the form of installed with radial displacements of semirings, the diameter of which, when closed, is less than the outer diameter of the processed workpiece, moreover, an annular emnik under a matrix, and a tubular blank formed with spiral riffles calibrated by pushing its smooth calibration matrix punch through.

Another feature of the method according to the invention is that they use a calibration matrix with two spaced forming belts.

The combination of distinctive features ensured an increase in productivity by 40-45% and the accuracy of the formation of shells of semi-finished striking elements of a given profile in a controlled chamber for controlled crushing of the body when undermining aerodynamic fragments.

The installation of the tool rod on the pusher with the possibility of axial rotation in the opposite direction to the spirals of the protrusions ensures automatic screwing of the machined shell of the projectile when it abuts against the ring puller, eliminating tribodynamic loads on the extended tool to form a complete profile of corrugations of each direction in one pulling operation.

The execution of a puller in the form of sliding half rings with a hole diameter in the closed position is guaranteed to be less than the caliber of the projectile necessary for the longitudinal passage of the processed semi-finished product when the half rings are forcibly moved apart, and to prevent the joint movement of the machined case when reversing the tool.

In this case, the body abuts against the annular puller and is frictionally braked, and the tool, which is forcibly rotated in the opposite direction to the spiral corrugations, is automatically unscrewed from the longitudinally stationary body.

The formation of multi-starting corrugations in the first drawing operation with an inclination angle of (32-33) ° to the longitudinal axis of the tubular billet provides a supply of metal for flow along the deformation force vector when forming multi-way corrugations of the opposite direction to the desired inclination angle (30-31) °, in accordance with the geometry of the tool is the operation of the second broach, as a result of which a grid of semi-finished fragments of the correct rhombic shape is formed, providing the specified weight and size parameters of the damaging elements with the adjustable crusher ii shell casing, characterized by an increase in the affected area and range expansion fragments.

An additional calibration operation of the formed internal corrugated profile of the chamber of the shell of the projectile by pushing it through the matrix with a smooth punch is aimed at smoothing the irregularities of the profile of the corrugations from the free flow of metal along the direction of deformation during the second pull and possible transverse influxes of metal of the external profile.

The implementation of the calibration matrix with two spaced forming belts reduced the difference in the body of the projectile, with the exact orientation of its axis on two supports, and the strain loads on the tool increased service life.

The exclusion of asymmetric loads on the tool during operation and removal of products increased the resistance of an expensive tool by 2.5-3 times.

When calibrating the outer surface of the shell of the projectile, the excess metal is reactively displaced by the matrix in the transverse direction, with the shear being limited to the chamber by a smooth punch, which causes metal redistribution in the formed corrugations of the riffles, leveling their differences.

During calibration, metal hardening occurs to improve the strength characteristics of the projectile body and embrittlement during dimensional crushing.

Therefore, each essential feature is necessary, and their combination is sufficient to achieve a novelty of quality that is not inherent in the signs of disunity, that is, the technical problem posed in the invention is not solved by the sum of the effects, but by a new super-effect of the sum of the attributes.

The invention is illustrated by drawings, which have a purely illustrative purpose and do not limit the scope of the claims of the totality of the essential features of the formula.

The drawings depict a operational flow diagram of the formation of riffles:

in FIG. 1 - operation of the 1st broach;

in FIG. 2 is a section along AA in FIG. one;

in FIG. 3 - unscrewing the processed semi-finished product;

in FIG. 4 - operation of the 2nd broach;

in FIG. 5 - calibration of the corrugated shell;

in FIG. 6 is a matrix of a calibration operation.

On the slider 1 (Fig. 1) of the hydraulic press in radial bearings (not shown conditionally), a pusher 2 is mounted that carries the tool rod 3, on the working surface of which are made spiral multi-start protrusions 4 inclined to the longitudinal axis by an angle (32-33) °.

On the bed 5 of the press with the central receiving pipe 6, a matrix 7 is installed, equipped with an inlet cone 8 and a forming gauge belt 9.

Under the matrix 7 mounted ring puller 10, made of two symmetrical half rings 11 (Fig. 2), loaded with springs 12.

The method according to the invention is as follows.

The tubular billet "a" bottom is installed through the inlet pipe 6 in the inlet cone 8 of the matrix 7.

Next, with a stroke of the slider 1, the pusher 2, rigidly connected with the tool rod 3, is fed into the tubular blank blank "a" with emphasis in its bottom.

The movement of the workpiece "a" and the rod 3 with spiral projections 4 relative to the pine matrix 7 is carried out together, without relative rotation between them.

In this case, the blank “a” is pushed through the calibrating girdle 9, which is accompanied by a radial flow of metal, which fills the gaps between the spiral protrusions 4, as a result of which congruent riffles “b” are formed inside the blank “a”, tilted to the longitudinal axis by an angle (32- 33) ° (Fig. 5), moreover, the workpiece "a" is pushed behind the ring puller 10.

When carrying out the above-described operation of the 1st pull, the spring-loaded half rings 11 are forcibly shifted radially to the periphery, compressing the springs 12.

After the open end of the formed semifinished product “c” (Fig. 3) exits the annular puller 10 by the spring force 12, the half rings 11 are closed at a diameter smaller than the outer diameter of the formed semifinished product “c” with multiple start corrugations “b” inside.

Next, the tool rod 3 with the semi-finished product "c", paired with the formed flutes "b" with the protrusions 4, reverse the reverse stroke of the slide 1 through the pusher 2.

In this case, the semi-finished product “c” abuts against the annular puller 10 (closed half rings 11) and stops, while the rod 3, forcibly rotating around the longitudinal axis, is unscrewed from the braked semi-finished product “c”, lifted by the slider 1 to its original position, as a result of which instrumental protrusions 4 disengage from the formed spiral flutes “b” on the inner surface of the semi-finished product “c”, which is then gravitationally removed from the stamp.

In the operation of the 2nd broach (Fig. 4), the diameter of the forming belt 13 of the calibrating matrix 14 is made smaller than the corresponding diameter of the belt 9 of the matrix 7 in the 1st broaching operation by a predetermined volumetric strain, which ensures the required geometry of the semi-finished product "g" (Fig. 5 ) with multiple start flutes “b” of both opposite directions.

The instrumental protrusions 4 of the rod 3 in the 2nd draw operation are directed opposite to the direction of the spiral grooves “b” after the 1st draw and are inclined to the longitudinal axis of the semi-finished product “c” at an angle (30-31) °, which ensures the transverse flow of metal between the spiral protrusions 4 tool rod 3 with volumetric deformation.

In this case, a concomitant adjustment of the angle of inclination of the “b” riffles formed on the first pulling occurs under the action of compressive radial stresses, which results in the free flow of metal of these “b” riffles with the final inclination by a smaller angle, commensurate with the angle of inclination of the counter-directed riffles "B" formed on the operation of the 2nd broach, the sequence of actions of which completely repeats the above described on the operation of the 1st broach.

The corrugated semi-finished product "b" is calibrated by pushing it with a smooth punch 15 (Fig. 5) through the matrix 16 with two forming belts 17, the passage section of which corresponds to the caliber of the shell of the projectile.

The belts 17 are spaced from each other (Figs. 5 and 6), forming a guide base with guaranteed alignment with the tool (15-16), as a result of which practically zero difference in the products is ensured.

The calibrated semifinished product “g” is pushed by the punch 15 behind the annular puller 18, with which the processed semifinished product “g” is forcibly removed from the reversible punch 15, when the first one stops against the puller 18, while the punch 15 is moved by the slider 1 to the highest (initial) position and automatically deduced from the stamp.

Next, the cycle of work is repeated.

Comparison of the proposed technical solution with the closest prior art analogues did not reveal an identical match of the totality of the essential features of the invention.

The proposed differences in the method of forming a grid of semi-finished rhombic fragments on the inner surface of the shell shell shells are not obvious to the specialist in ammunition, which does not directly follow from the statement of the technical problem.

The proposed differences of the method, which do not directly follow from the statement of the technical problem, are not obvious to specialists in the bulk deformation of metals and ammunition.

The manufacture of shells corrugated from the inside according to the proposed set of interrelated technological operations and modes can be carried out in series at the current stamping production.

From the foregoing, we can conclude that the invention meets the conditions of patentability.

Claims (2)

 1. A method of manufacturing a fragmentation shell of a shell of a projectile, comprising forming on the inner surface of a tubular billet with a bottom of multi-helical riffles of the opposite direction, forming a network of rhombic protrusions, for two successive reduction operations, which are carried out by pulling a tubular billet mounted on a central rod with uniformly distributed tool spiral projections with an emphasis on the mentioned rod in the bottom of the tubular billet, through matrices of different diameters by feeding the central rod with a pusher, while the treated tubular billet is removed from the central rod by reversing it when braking the processed billet on an annular puller, characterized in that the first reduction operation is carried out using a central rod with instrumental spiral protrusions, the inclination angle of which is 32- 33 °, and in the second reduction operation using a central rod with an angle of inclination of instrumental spiral projections of 30-31 °, while The machined tubular billet is removed by unscrewing the central rod from it by rotating it when reversed relative to the pusher in the direction opposite to the direction of the instrumental spiral protrusions, while braking the machined billet on the ring puller in the form of half-rings mounted with the possibility of moving in the radial direction, the diameter of which when closing is smaller than the outer the diameter of the processed workpiece, and the annular puller is located under the matrix, and the tubular workpiece with the form calibrated spiral grooves are calibrated by pushing it with a smooth punch through the calibration matrix. 2. The method according to p. 1, characterized in that they use a calibration matrix with two spaced forming belts.

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