Method of making grid of grooves on inner surface of shell and device therefor

FIELD: technological processes.

SUBSTANCE: invention can be used for production of shells with grid of grooves on inner surface. On inner surface of hollow billet grid of corrugated grooves are shaped by female die for pressing with conical working surface with taper angle of 10-45° and central mandrel with mesh of corrugated ledges. Forming grooves is carried out successively in sections. At that, on hollow billet form conical section is formed by crimping of latter with crimping factor of K = 1.2…1.8. For this purpose, hollow billet is pushed through matrix for pitch multiple to workpiece length. Corrugated ledges of rod working surface made with taper angle of 10-45°, are introduced into inner surface of workpiece conical section. Said conical section is formed with mesh corrugated grooves into cylindrical section. Shaping is performed by moving hollow billet in axial direction at pitch with simultaneous forming of next section of conical shape on it.

EFFECT: production of grid of grooves of various shape and dimensions with simultaneous reduction of number of operations.

2 cl, 3 dwg, 1 ex

 



 

Same patents:

FIELD: metallurgy.

SUBSTANCE: round blank is swaged by two mutually perpendicular die pairs. One die pair has smooth work surface, the other die pair features carved grooves on the work surface. Side surfaces of carved grooves are oriented at 120° angle to each other. Work surfaces of dies are shifted against each other along forging axis. First, round blank is swaged by the die pair with smooth work surface in several deformation cycles. Each cycle includes several runs. Thus, octagonal profile is obtained. Ratio of inscribed circle diameter of this profile to side surface length of carved groove in a die does not exceed 1.93. In each deformation cycle, the blank is turned around its axis before each run in sequence at π/2, π/4 and π/2 angles. Before each deformation cycle, gap between work surfaces of dies with smooth surface is reduced. Finally, swaging is performed with two die pairs at the same time to obtain hexagonal profile.

EFFECT: extended processing capabilities of radial forging to obtain high-quality hexagonal profiles.

20 dwg

FIELD: metallurgy.

SUBSTANCE: cyclic swaging of a workpiece is performed simultaneously with two mutually perpendicular pairs of strikers. A hexagonal section is obtained in each cycle. Strikers of one pair has a smooth working surface. Strikers of the second pair have cutout grooves with surfaces inclined to each other at an angle of 120°. Working surfaces of mutually perpendicular strikers are offset relative to each other along a forging axis by a value exceeding the length of the working surface of the striker. Swaging of the workpiece in each cycle, except for the first one, is performed by a value that does not exceed difference of diameters of the described circle of the hexagonal section obtained in the previous cycle, and an inscribed circle of the hexagonal section obtained in the considered cycle. After each cycle, the workpiece is turned about the forging axis through angle π/n, where n=6 - number of faces of a hexagonal section.

EFFECT: obtaining quality hexagonal sections at enlargement of the range of initial workpieces and obtained items.

9 dwg

FIELD: process engineering.

SUBSTANCE: invention relates to metal forming and may in production of hexagonal sections by radial forging. Blank is squeezed by two mutually perpendicular airs of flat dies. Working surfaces of flat dies of one pair are shifted along hammering axis relative to those of another pair. Magnitude of said shift is larger than the length of flat die working surface. Flat dies of one pair have smooth working surface. Flat dies of another pier feature working surface composed of cut passes with surfaces arranged at 120 degrees. Said cut passes are shifted relative to each other to get hexagonal section at next to last forging pass in said cut passes with different spacing there between. Spacing between working surfaces of flat dies with smooth working surface is set smaller then the least distance between hexagon faces made at next the last pass. Blank before final pass is turned over through 60 degrees to set said faces at larger spacing there between from the side of flat dies with smooth working surface.

EFFECT: higher quality of sections.

4 dwg, 1 ex

FIELD: process engineering.

SUBSTANCE: invention relates to metal forming and can be used in production of ribbed panels intended for bodies of compartments, bulkheads, wings and other parts of aircraft and spacecraft. Heated blank is strained at the rate of 0.01-10 mm/s, in steps over the sections, with gradual forming of the entire surface. Area of said sections is at least two times smaller than that of said blank. Straining is executed at the device to be secured in die unit for isothermal die forming. Proposed device comprises top and bottom plates, heaters, female die, male dies with cavities shaped and sized to panel ribs and at least two male die holders. The latter displace in guide columns. It includes sliding thrust plates with drive. One male die is rigidly fixed in male die holder. Other male dies are fitted in their holders and spring-loaded and can displace in direction of forming force application.

EFFECT: enhanced processing performances.

2 cl, 5 dwg

FIELD: weapons.

SUBSTANCE: present invention pertains to military equipment and can be used when making high-precision small arms. A mandrel bar or puncheon is put into the channel of barrelled work-piece and a channel with grooves is formed through rotary forging or drawing. The surface of the work-piece channel is pre-activated and then coated with a composition. The composition assumes functions of lubricant material and provides for a wear-proof coating when making the channel with grooves. The composition contains a mixture of homogeneous and heterogeneous catalysts and dispersion reinforcement systems in viscous carrier and natural minerals in the class of carbonates, halogenides, sulphates, silicates and oxides with combined concentration of 20-40 wt %. The natural minerals are modified until formation of a porous layer of minerals on the surface of the channel, forming hydrophilous-hydrophobic splices, filled with organic ligands. The work-piece then undergoes thermal processing for 2-4 hours at 130-140°C, after which a channel with grooves and a wear-proof coating are simultaneously formed.

EFFECT: reduced labour input in manufacturing with improved tactic-technical and operational characteristics of the barrel at the same time.

2 cl, 5 dwg

FIELD: metallurgy.

SUBSTANCE: hollow cylinder stock is brought with its not subject to treatment end to clamping device and fixed in it. After that a mandrel with a coaxially inserted and lengthwise set off spike is introduced into the end of the zone of the stock, subject to treatment. Its free end passes up to the clamping device. The end of the spike is brought after that in an axial direction of the stock into contact with geometric locking with the clamping device. The mandrel together with the clamping device and stock are axially passed through a stationary technological position. To facilitate inside and, if necessary, outside profiling, the surface of the stock along the section subject to treatment is radially effected in this position. The device contains the first and axially installed to it the secondary spindle straddles, axially set off to the first spindle straddle mandrel and the stationary technological position with cold fabrication tools for operating radially to the axis of the straddle. The clamping device is located coaxially against the axis of the first straddle and it is designed to be set off against the technological position. At that the technological position is situated stationary between the spindle straddles. There is also the movable spike axial-symmetrically situated inside the mandrel.

EFFECT: extended technological capabilities.

24 cl, 7 dwg

FIELD: plastic working of metal, possibly forming on inner surface of tubular blanks with bottom multi-stat helical riffles of mutually opposite directions at manufacturing fragmentation type envelope of ammunition.

SUBSTANCE: riffles form grid of rhombic protrusions. In order to form such riffles, tubular blank is reduced by two successive operations. At each operation tubular blank and punch with helical protrusions are together pulled through sizing die. Each operation is realized at least during two transitions while punches whose length is multiply less that length of blank are used. Common pulling through of blank and punch during first transition of each reduction operation is realized while punch rests upon bottom of blank. Between transitions at each reduction operation punch is unscrewed from blank with formed helical riffles for forming between punch and blank band of engagement of helical protrusions of punch and helical riffles of blank. Said band is used at next reduction transition for resting punch and for providing desired direction of formed helical riffles.

EFFECT: enlarged functional and manufacturing possibilities of method.

5 dwg

FIELD: plastic working of metals, possibly manufacture of parts with shaped contour, for example polyhedral parts.

SUBSTANCE: method comprises steps of forming round cross section semi-finished product; embossing its surface for forming relief in the form of alternating protrusions and recesses and shaping curvilinear contour of said relief. Size of shaped contour corresponds to size of profile of ready part. Diameter of described circle passing through apexes of curvilinear protrusions is selected in range consisting of (1.15 - 1.35) of diameter of inscribed circle passing through apexes of recesses of part. Curvilinear contour of protrusions and recesses is shaped due to acting upon semi-finished product by means of shaping tool having profile of working surface in the form of curvilinear protrusions. The last have curvature radius with curvature centers spaced from part symmetry center by distance exceeding by 1.65-1.8 times distance from said symmetry center till curvature centers of curvilinear protrusions of part. Curvilinear recesses are alternated with curvilinear protrusions on working surface of shaping tool. Diameter of described circle passing through apexes of said recesses consists (1.15 - 1.35) of diameter of inscribed circle passing through apexes of curvilinear protrusions.

EFFECT: enlarged manufacturing possibilities of method and apparatus.

8 cl, 8 dwg

The invention relates to the processing of metals by pressure and can be used in forging and stamping upon receipt of long panels with ribs

The invention relates to the processing of metals by pressure and can be used in forging and stamping upon receipt of long panels with single-sided stiffeners used, for example, in aircraft construction

FIELD: metallurgy.

SUBSTANCE: matrix for upsetting contains insert and shroud ring. The insert is pressed in the shroud ring with variable tension through height of the shroud ring or insert. The mating external surface of the insert and internal surface of the shroud are made cone. The variable tension between these surfaces is created by their making with various differences between the ring internal diameter and outside diameter of the insert at opposite ends of the matrix. The variable tension Δ is selected based on expression: Δ = Δ1-Δ2 = (0.02…0.34) mm, where Δ1 is tension between the mating surfaces of the insert and shroud ring from side of the matrix mirror, Δ2 is tension between the mating surfaces of the insert and shroud ring from side of the matrix end face opposite to the matrix mirror.

EFFECT: increased cyclic resistance and strength of the matrix, increased its production effectiveness.

2 dwg

FIELD: process engineering.

SUBSTANCE: invention relates to metal forming and may be used in forging of cross-pieces. Male die is arranged at top mould top plate. Bottom female die is arranged at bottom plate with crossbar. Top and bottom female dies have joint surface with equal central and peripheral sections. Top female die is coupled with crossbar by ties and arranged to displace relative to bottom female die to make a closed die chamber. Ejector is arranged in bottom female die to rest via spring-loaded pusher on said crossbar. Peripheral sections of parting surface of said female dies are inclined to side surface thereof. Said ties are arranged in through straight slots made at opposite side walls of female dies parallel with the mould mirror axis. This results in tight camping of female dies over forged-piece contour owing to plastic deformation of macro irregularities and waviness unavoidable after finishing of female die contact surfaces.

EFFECT: accurate alignment of female dies.

3 dwg

FIELD: machine building.

SUBSTANCE: punch for broaching is made as a body of rotation with two holes. The outer diameter of the punch is alternating. The said diameter at the punch length section from its front end face being equal to the inner diameter of the produced hollow billet is equal to the said inner diameter of the hollow billet. Along the remaining length section, the punch diameter is constant and is by 2 mm less than the inner diameter of the hollow billet. One of the holes is through, has the diameter alternating by the length and the axis matching the punch axis. The diameter of the said hole at the length section from the punch front end face equal to its maximal outer diameter is equal to 2/3 of the said punch diameter. Along the remaining length section, the hole diameter is constant and is by 2 mm greater than the hole diameter at its length from the punch front end face. The second hole is fitted by an axis crossing the punch axis at the right angle. The axis of the second hole is set at the distance from the punch front end face equal to 4/5 of the punch length. The diameter of the second hole is constant along the whole hole length and is equal to 5 mm.

EFFECT: improved quality of broached billets due to the reduction of their wall thickness variation and elimination of faults, reduction of friction at the outer and inner surface of the punch.

6 dwg, 1 ex

FIELD: process engineering.

SUBSTANCE: invention relates to metal forming and can be used of forging of ingots and billets from various steels and alloys. Flats of proposed device are secured their appropriate holders by clamps. Flats have grooves to accommodate clamps while side flat holders have recesses for fixation of flats. L- or U-like clamps can be coupled with uncoupled from flats with the help of springs fitted in bores made in flat holders. Clamps can be retained, at uncoupling from flats, on either flat holders or coupling studs extending there through. At least one key is made on clamp surface on the side of side flat holders. At least one grieve is made on the surface of side flats and side flat holders.

EFFECT: flats can be detached from holders without removal the clamps.

6 cl, 15 dwg

FIELD: process engineering.

SUBSTANCE: invention relates to metal forming and can be used in production of ribbed panels intended for bodies of compartments, bulkheads, wings and other parts of aircraft and spacecraft. Heated blank is strained at the rate of 0.01-10 mm/s, in steps over the sections, with gradual forming of the entire surface. Area of said sections is at least two times smaller than that of said blank. Straining is executed at the device to be secured in die unit for isothermal die forming. Proposed device comprises top and bottom plates, heaters, female die, male dies with cavities shaped and sized to panel ribs and at least two male die holders. The latter displace in guide columns. It includes sliding thrust plates with drive. One male die is rigidly fixed in male die holder. Other male dies are fitted in their holders and spring-loaded and can displace in direction of forming force application.

EFFECT: enhanced processing performances.

2 cl, 5 dwg

FIELD: metallurgy.

SUBSTANCE: die includes upper and lower halves with prints forming a stream, a box and a flash bridge. The bridge is made by connection of a horizontal section to a section formed by a projection on one half of the die by a bore on the other half of the die. The projection is restricted by some part of a circle with radius R1, and the bore is made with radius R2. Centre of bore radius R2 is offset relative to the centre of projection radius R1 to the zone of the stream with larger surface areas of cross sections along the perimeter of the flash bridge and to the side from the zone of the stream with smaller surface areas of cross sections. With that, offset is performed by a value that is variable along the perimeter of the flash bridge and does not exceed 0.8h, where h - design height of the flash on the flash bridge.

EFFECT: reduction of forging force and decrease of distortion of forged pieces, forging inclinations and thickness of the flash.

2 dwg

FIELD: metallurgy.

SUBSTANCE: proposed tool comprises pot, female die and coupled dummy block and stem. Screw coupling is tightly secured in said stem by thread joint and key. Dummy block is jointed with screw coupling by bayonet joint composed of ledges on screw coupling and recesses in dummy block and locked by resilient split pin.

EFFECT: ruled out dummy block locking in the pot.

2 cl, 2 dwg

FIELD: metallurgy.

SUBSTANCE: stock is exposed to closed deposition in a matrix channel and double-sided extrusion. Extrusion is carried out into upper and lower wedge cavities formed by upper and lower wedge puncheons. Then the specified puncheons are extracted from the matrix channel and turned around the axis by the angle 180°. By means of these puncheons they perform the subsequent loading of the stock with filling of the upper and lower wedge cavities at the other side. The cycle is repeated, afterwards wedge puncheons are replaced to puncheons with an end surface arranged perpendicularly to the axis of the stock. Closed deposition is carried out giving initial shape to the stock. Wedge puncheons and matrix channel have round or rectangular shape.

EFFECT: invention excludes formation of cracks, cavities, folds and clamps in a stock and provides for higher resistance and operability of a device.

3 cl, 7 dwg

FIELD: process engineering.

SUBSTANCE: invention relates to metal forming and may be used in producing 5.45-30 mm calibre gun barrels. Hollow actuating centre is intended for radial squeezer for reduction of pipe billet with inner chamfer on one end. Actuating centre comprises body with cylinder and cavity for moving central sleeve with outer cone for said inner chamfer. Damping element is arranged between central sleeve rear end and body. Actuating centre is equipped with taper sleeve with teeth at front located inside conical cavity made on the side of body front end. Said sleeve is locked by pins relative to said body. Said pins feature small and large diameter parts. Large diameter parts are located in the body and conical sleeves lengthwise grooves to thrust by their rear ends against sleeve lengthwise rear ends. Small diameter parts are fitted in body cylinder bores and extend therefrom with nuts screwed on in seats made at body rear end.

EFFECT: better reparability, longer life, lower costs of products.

1 dwg

FIELD: process engineering.

SUBSTANCE: invention relates to metal forming and can be used for production of articles with high mechanical properties by forming fine-grain and homogeneous structure. This die block comprises band, male die and female die. Female die has parallel inlet and outlet channels. Said channels feature geometrically identical cross-sections and are interconnected by intermediate channels. Intermediate channel is arranged at the angle of 120°≤θ≤135° to inlet and outlet channels. Intermediate channel cross-section over its entire length in the plane perpendicular to axes of said inlet and outlet channels geometrically identical to cross-section of said channels.

EFFECT: high mechanical properties by forming fine-grain and homogeneous structure.

5 dwg, 1 tbl

FIELD: machine building.

SUBSTANCE: device includes a container with located in it blank, press-washer, die, press-needle made on work area with helical cavities and shoulders, and connected with drive gear ensuring press-needle rotation with speed corresponding to the pressing rate. Stable spiral flow of the blank metal in the deformation area, and reduced press force are ensured due to that die is made with lead taper and calibrating areas, at the work area of the press-needle adjacent to the press-needle body and corresponding to length of the lead area of the die the spiral cavities are made with varying pitch, at that width and depth of each cavity reduce towards the calibrating area of the die, and ratio width to depth of the cavity is permanent value for all cross-sections. Cavities pitch over the work area of the press-needle corresponding to length of the lead area of the die is determined by equation.

EFFECT: improved design.

2 cl, 3 dwg

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