RU2715397C1 - Method for processing edges of laminated torsion bar of helicopter rotor and device for its implementation - Google Patents

Abstract

FIELD: technological processes.

SUBSTANCE: invention relates to electropolishing and electric treatment of parts from alloyed steels based on ion transfer and can be used for rounding edges of plate-like parts, for example torsion of rotors of helicopters. Proposed method comprises assembly of torsion bars into package with alignment of contours and processing of edges in package. Note here that torsion bar assembly is performed via flat gaskets repeating torsion contour with distance from edges to allow free access to torsion bar machining with superimposition of screens repeating configuration and location of gaskets on outer surfaces of extreme torsion bars. Package of torsion bars is immersed in medium of granules made of anion exchangers impregnated with solution of electrolyte, which provides electric conductivity of granules and ion breakdown of metal. Granules are brought into vibration motion ensuring uniform flushing of torsion bar edges. An electric potential is supplied to the torsion and granules, which ensures rounding of edges and obtaining of the specified roughness of the surface. Device consists of package holder and device for processing edges of torsions in medium of granules.

EFFECT: increased quality of polishing and rounding of laminated torsion bar edges, and also improved performance of torsion bars with reduction of labor intensity of processing process.

10 cl, 3 dwg

Description

The invention relates to the technology of electric polishing and electric processing of parts from alloy steels based on ion transfer and can be used to round the edges of plate parts, for example, torsions of rotors of helicopters.

The rotor of the aircraft, containing V-shaped torsions connected to the sleeve and through vertical hinges with adapters for fastening the blades, shrouds of composite material placed around the torsions, while at one end of each is fixed a lever for controlling the angle of installation of the blades and a spherical bearing worn on a finger mounted on the sleeve, and the other end of the casing through a vertical hinge attached to the torsion bar and to the adapter for attaching the blade, an elastic element located in the casing along the axis of the sleeve between the blade mounting adapter and the blade angle control lever, while the cut end of the elastic element is rigidly connected to the eyes of the blade adapter, and the opposite end is inserted into the guides on the blade angle control lever [RF patent No. 2033943, AIRCRAFT LOAD SCREW. Helicopter scientific and technical complex. N.I. Kamov, 1991], (similar rotor designs are also presented in RF patent No. 2289530).

Lamellar torsions of the rotors of helicopters are made of high-strength alloy steels combining high strength and ductility provided by their composition, heat treatment and plastic deformation. The composition of such steel should provide after quenching at room temperature to obtain a pure austenitic structure. These steels are subjected to deformation at a temperature not exceeding the temperature of recrystallization, and then cooled to room temperature. For example, steels are known whose mechanical properties after quenching and plastic deformation at 400-500 ° C with a degree of 60-80% reach 180-200 kgf / mm ² , 0.2 = 140-170 kgf / mm ² , = 20- 30% (A.P. Gulyaev "Metallurgy". - M .: "Metallurgy", 1977, p. 335-396).

However, plate torsion bars made of alloy steels (for example, VNS9-Sh steel) have a thickness of the order of 0.3 mm and the quality of processing of their edges and surface largely determines the operational properties of torsion bars.

Currently, polishing of plate torsion bars and rounding of their edges is carried out by mechanical methods, which leads to a deterioration in the quality of the surface layer (roughness, degree of hardening, heterogeneity of the physical and mechanical properties of the material of the surface layer, etc.), which, given the insignificant thickness of the plate parts , leads to a sharp deterioration in the operational properties of parts.

Known methods of polishing based on the use of various physico-mechanical, mechanical and chemical effects. Due to the fact that the torsions of the rotors of helicopters made of alloy steels are highly sensitive to stress concentrators, the occurrence of defects during their processing is unacceptable, since during operation, defects formed on the surfaces and edges of the torsion bars lead to their destruction. Therefore, the development of methods for polishing and rounding the edges, allowing to obtain high-quality torsion surfaces with high environmental friendliness and productivity of the coating removal process, is a very urgent task.

The most promising methods for processing edges and polishing parts from alloyed flocks are electrochemical methods [Griliches S.Ya. Electrochemical and chemical polishing: Theory and practice. Effect on the properties of metals. L., Mashinostroenie, 1987.], while the most interesting for the area under consideration are the methods of electrolyte-plasma polishing (EPP) of parts [for example, Patent GDR (DD) No. 238074 (A1), IPC C25F 3/16, publ. 08/06/86., As well as Patent RB No. 1132, IPC C25F 3/16, 1996, BI No. 3].

There is also a method of processing edges and polishing metal surfaces, including anode processing in an electrolyte [RB Patent No. 1132, IPC C25F 3/16, 1996, BI No. 3], as well as a method for electrochemical polishing [US Patent No. 5028304, IPC V23H 3/08 , C25F 3/16, C25F 5/00, publ. 07/02/91]

Known methods for electrochemical processing of edges and polishing do not allow to obtain high-quality edges and surfaces of thin-walled parts from alloy steels, without significant etching of the material of the surface layer.

There is also known a method of electrolyte-plasma polishing of a part, comprising immersing the part in an electrolyte, forming a gas-vapor shell around the workpiece surface and igniting a discharge between the workpiece and the electrolyte by applying an electric potential to the workpiece [RF Patent No. 2552203, IPC C25F 3/16. Bull No. 6, 2015].

However, the known method [RF Patent No. 2552203], provides for the processing of parts from titanium alloys and cannot be used to process parts from alloy steels, without compromising the quality of the torsion bars. The prototype method [RF Patent No. 2552203], includes processing the part in an aggressive etching solution (an aqueous solution containing from 3 to 7 wt.% Hydroxylamine hydrochloric acid and from 0.7 to 0.8 wt.% NaF or KF as fluorine-containing compounds, and polishing is carried out at a temperature from 70 ° C to 90 ° C). These factors do not allow the use of the prototype method for processing torsion bars, since it leads to a sharp deterioration in their operational properties due to the formation of stress concentrators and deterioration of roughness.

Closest to the claimed technical solution is a method of processing edges of the same size and configuration of plate parts, including assembling the plate parts in a bag with combining their contours and processing the edges in a bag (RF patent No. 2560814, IPC V23C 3/12. The method of preparing the edges of sheet blanks cutting for welding sheet welded blanks, publ.: 08.20.2015 bull. No. 23.) Moreover, the sheet blanks are collected in a bag, clamped in a clamping device and milling in one or more passes.

However, the known method of processing the edges of plate parts in a package does not allow rounding of the edges of the torsion bars, and mechanical cutting of the edges leads to a decrease in the quality and operational characteristics of the parts due to the formation of stress concentrators.

A device for electropolishing metal parts, made in the form of a metal electrically insulated from the outside of the container with an open top [US Application No. 1980200863. IPC V24V 37/04 Removable electro-mechanical device for burnishing and smoothing metal parts. Publ. 07/19/2018] contains an electrolyte container, a support element for accommodating the workpieces and a system for moving and additional mechanical impact on the processing process.

However, the known device for electropolishing [US Application No. 1980200863] have low productivity and cannot be used to process the edges of torsion bars.

The closest technical solution chosen as a prototype of the device is a device for processing the edges of plate parts, consisting of a holder for a package of plate parts and means for processing edges (RF patent No. 2560814, IPC VC 3/12. A method for preparing the edges of sheet blanks by cutting for welding welded sheet blanks, publ.: 08.20.2015 bull. No. 23.).

However, the known device (RF patent No. 2560814) does not allow rounding of the torsion edges and their polishing.

The task to which the invention is directed is the development of processes for polishing torsion bars and rounding their edges, which allows to obtain high-quality surfaces of plate torsion rotors of helicopters made of alloy steels and to provide increased operational characteristics of torsion bars while reducing the complexity of their processing.

The technical result of the present invention is to improve the quality of polishing and rounding of the edges of the plate torsion bar, as well as to increase the operational characteristics of the torsion bars while reducing the complexity of the processing process.

The technical result is achieved due to the fact that in the method of processing the edges of the plate torsion of the rotor of the helicopter, which includes assembling the torsion bars in a package with combining their contours and processing the edges in a package, in contrast to the prototype, the assembly of torsion bars in a package is made through flat gaskets that repeat the torsion contour with a deviation from the edges by an amount that provides free access to the processing of the edges of the torsion bars, with overlapping screens that repeat the configuration and location of the said gaskets on the outer surfaces to of the torsion bag of the package, immersion of the torsion bag in the medium of granules made of anion exchangers, impregnated with an electrolyte solution, providing electrical conductivity of said granules and ionic ablation of the metal with removal of microprotrusions from its surface, contacting the processed edges of the torsion bar with said granules, bringing said granules into vibrational motion, providing uniform washing with granules of the edges of the torsion bar, the supply to the torsion bar and granules of the electric potential, providing ion ablation of metal and with their edges machined surface polishing and rounding the edges of said granules in a medium to obtain a predetermined surface roughness and a predetermined radius of rounding edges torsions, wherein said granules are brought into a reciprocating motion with respect to the processed edges torsion.

In this case, the following additional features of the method are possible: metal plates are used as gaskets, and metal plates coated on the side of contact with torsion by a layer of dielectric material are used as screens, and the value of the mentioned deviation from the edges is taken from 0.5 to 4 mm; as gaskets and screens use plates of dielectric material, and the magnitude of the mentioned deviation from the edges is taken equal to from 0.5 to 4 mm; as the anion exchangers of said granules, ion-exchange resins obtained based on the copolymerization of either polystyrene or polyacrylate and divinylbenzene are used, the granule sizes being selected from a range from 0.1 to 0.8 mm; electrical polishing with granules is carried out by supplying a positive electric potential to the torsion, and a negative electric potential of 25 to 35 V to the granules; granules are electropolished in a pulsed mode with a polarity reversal, with a pulse frequency range of 20 to 100 Hz, a pulse period of 50 μs to 10 μs, and a current amplitude of positive polarity during a pulse of +50 A and their duration 0.4 to 0.8 μs, with a current amplitude of negative polarity during a pulse - 20 A, and their duration 0.2 to 0.4 μs, with a rectangular shape of the current output pulses and the duration of pauses between pulses from 49.6 μs to 9.2 μs; they use torsion made of alloy steel, and one of the following aqueous solutions is used as electrolytes for impregnating the said granules from anion exchangers: either NH ₄ F, concentration from 6 to 24 g / l, or NaF, concentration from 4 to 18 g / l or KF with a concentration of 35 to 55 g / l, or a mixture of NH ₄ F and KF with an NH ₄ F content of 5 to 15 g / l and KF from 30 to 50 g / l, or a mixture of NaF and KF with a content NaF - from 3 to 14 g / l and KF - from 35 to 60 g / l, or a mixture of NH ₄ F and NaF with an NH ₄ F content of from 4 to 12 g / l and KF - from 35 to 55 g / l or mixtures of NH ₄ F, NaF and KF with a content of NH ₄ F from 3 to 9 g / l and KF from 20 to 30 g / l, and NaF from 10 up to 25 g / l, or a mixture of NH ₄ F and HF with an NH ₄ F content of from 5 to 15 g / l and HF from 3 to 5 g / l, or from 8 to 14% aqueous NaNO ₃ solution, or electrolytes compositions, wt. %: (NH ₄ ) ₂ SO ₄ - 5; Trilon B - 0.8, or containing sulfuric and phosphoric acid, a block copolymer of ethylene oxide and propylene and the sodium salt of sulfonated butyl oleate in the following ratio of components, wt. %:

Sulfuric acid - 10-30

Orthophosphoric acid - 40-80

Block copolymer of ethylene oxide and propylene - 0.05-1.1

Sodium salt of sulfonated butyl oleate - 0.01-0.05

Water - The rest.

after rounding the edges of the torsion bars, the package is disassembled and each of the torsion bars is polished in the medium of the above-mentioned granules to obtain a given surface roughness.

The invention is illustrated by drawings. In FIG. 1 shows a plate torsion with machined edges. In FIG. 2 shows the torsion bars assembled in a package through gaskets. In FIG. 3. - shows the process of processing the edges of the torsion bar in granules, anion exchangers, impregnated with electrolyte. Figures 1, 2 and 3 contain: 1 - plate torsion bar; 2 - the edges of the plate torsion bar; 3 - bare section on the end parts of the torsion bar; 4 - screen; 5 - a package of torsion bars; 6 - gaskets between torsion bars; 7 - electrical insulation coating on the screen; 8-working container; 9 - granules made of anion exchangers impregnated with an electrolyte solution. (The black arrows show the reciprocating movement of the flow of granules relative to the package of torsion bars.

The inventive processing of the edges of the plate torsion of the rotor of the helicopter is as follows. Processed torsion 1 (Fig. 1) is collected in package 5 with the combination of their contours (Fig. 2). The assembly of the torsion bars in the package 5 is carried out through flat gaskets 6, repeating the contour of the torsion 1 with a deviation from the edges 2, leaving bare sections 3 on the end parts of the torsion 1, providing free access to the processing of the edges 2 of the torsion 1, with overlapping screens 4 repeating the configuration and location gaskets 6 on the outer surfaces of the extreme torsion bars 1 of the package 5. The deviation 3 (the bare part of the torsion bar) from the edges 2 is taken equal to from 0.5 to 4 mm. As spacers 6, metal plates are used that make electrical contact between the torsion bars 2 in package 5 and ensure the electrical conductivity of the entire package 5. As screens 4, metal plates coated with a layer of dielectric material from the side of contact with the torsion bars 2 are used. Metal screens 4 with an electrically insulating coating 7 take to ensure rigidity when clamping torsion bars 1 in package 5. When ensuring electrical contact between torsion bars 1 in package 5, you can use gaskets 6 from dielectric -parameter material. In this case, the processing area of the package 5 will decrease and the likelihood of deformation of the torsion bar 1 will decrease, when the pressure is pressed through the metal gaskets 6.

The processing of the edges 2 in the bag 5 (Fig. 3) is performed by immersing the bag 5 of torsion 1 in a working container 8 in a medium of granules 9 made of anion exchangers impregnated with an electrolyte solution that provides electrical conductivity of the granules 9 and ion ablation of the metal to remove microprotrusions from the surface of the edges 2 torsion 1. When immersing the package 5, the machined edges 2 of torsion 1 are contacted with granules 9, the granules 9 are brought into vibrational motion, which ensures uniform washing with granules 9 of edges 2 of torsion 1, they are fed to torsion 1 and granules 9 are electrically potential, providing ionic ablation of metal from the processed surface of the edges 2, their polishing and rounding of the edges 2 in the medium of granules 9 to obtain a given surface roughness and a given radius of rounding of the edges of the torsion bars 1. Electropolishing with granules 9 can be carried out either by applying positive to torsion 1, and to granules 9 negative electric potential from 25 to 35 V, or in a pulse mode with a polarity reversal, with a pulse frequency range of 20 to 100 Hz, a pulse period of 50 μs to 10 μs, with a current amplitude of positive polarity during a +50 A pulse and their duration 0.4 to 0.8 μs, with a current amplitude of negative polarity during a pulse - 20 A, and their duration 0.2 to 0.4 μs, with a rectangular shape of current output pulses and duration of pauses between pulses from 49.6 μs to 9.2 μs. When processing the edges 2, the granules 9 are driven in reciprocating motion relative to the machined edges 2 of the torsion 1 (Fig. 3).

When processing edges 2 of torsion 1, made of alloy steel, one of the following aqueous solutions is used as electrolytes for impregnating granules 9 from anion exchangers: either NH ₄ F, concentration from 6 to 24 g / l, or NaF, concentration from 4 to 18 g / l, or KF with a concentration of 35 to 55 g / l, or a mixture of NH ₄ F and KF with an NH ₄ F content of 5 to 15 g / l and KF from 30 to 50 g / l, or a mixture of NaF and KF when the content of NaF is from 3 to 14 g / l and KF is from 35 to 60 g / l, or a mixture of NH ₄ F and NaF when the content of NH ₄ F is from 4 to 12 g / l and KF is from 35 to 55 g / l, or a mixture of NH ₄ F, NaF and KF with an NH ₄ F content of from 3 to 9 g / l and KF from 20 to 30 g / l, and NaF from 10 to 25 g / l, or a mixture of NH ₄ F and HF with an NH ₄ F content of from 5 to 15 g / l and HF from 3 to 5 g / l, or from 8 to 14% aqueous NaNO ₃ solution, or in electrolytes of the compositions, wt. %: (NH ₄ ) ₂ SO ₄ - 5; Trilon B - 0.8, or containing sulfuric and phosphoric acid, a block copolymer of ethylene oxide and propylene and the sodium salt of sulfonated butyl oleate in the following ratio of components, wt. %:

Sulfuric acid - 10-30

Orthophosphoric acid - 40-80

Block copolymer of ethylene oxide and propylene - 0.05-1.1

Sodium salt of sulfonated butyl oleate - 0.01-0.05

Water - The rest.

After rounding the edges 2 of the torsion 1, the package 5 is disassembled and each of the torsion 1 is polished in the medium of granules 9 to obtain a given surface roughness.

When processing the edges 2 of the torsion bar 1, two flat screens 4 are used as the holder of the package 5, with a clamping device providing clamping through the screens 4 of the torsion bars 1 assembled through the gaskets 6 into the package 5, and the screens 4 and gaskets 6 follow the contour of the torsion 1 with deviation from the edges by an amount that provides free access to the processing of edges 2 of torsion 1. As a means for processing the edges 2 of torsion 1, a container 8 with electrically conductive granules 9 is used, which ensures complete immersion of the package 5 of torsion 1 in the medium l 9, and the container 8 is equipped with current leads to the container 8 and to the electrodes insulated from the container, a vibrator that provides vibrational movement to the said granules with a frequency of 50 ... 400 Hz, a device that provides reciprocating movement and rotation of the torsion bar package 1.

The reciprocating movements of the granules 9 and their vibration allow for uniform processing of the edges 2 of the torsion 1 and the entire surface of the torsion 1 during subsequent polishing after removal from the package 5.

When implementing the method, the following processes occur. During the reciprocating movement of the granules, they collide with the treated surface of the torsion packet or separately polished torsion. In this case, collisions between granules also occur in the entire volume of the working container, thus creating uniform conditions for the flow of electrical processes for the entire volume of granules. In this case, electrical processes, for example, between a part (anode) and granules (cathode) occur due to the contact of the mass of electrically conductive granules with each other and with the negative potential of the working container and / or the electrodes (cathodes) introduced into the mass of granules under the negative potential. In the collision of granules with microprotrusions on the workpiece surface, ionic ablation of the mass from microprotrusions occurs, as a result of which the surface is leveled, its roughness decreases and surface polishing and rounding of the plate edges occur.

The following studies were also conducted on the processing of the edges of torsion bars of alloy steels. An unsatisfactory result (N.R.) was considered a result in which there was no effect of rounding the edges of the torsion bar and polishing its surface. Upon obtaining the effect of rounding edges and polishing, the result was considered satisfactory (U.R.)

The following processing modes were used.

Granules made of anion exchangers and impregnated with an electrolyte solution of sizes from 0.1 to 0.4 mm (0.05 mm (N.R.), 0.1 mm (U.R.), 0.2 mm (U.R .), 0.4 mm (U.R.), 0.6 mm (U.R.), 0.8 mm (U.R.), 1.1 mm (N.R.)).

The anion exchangers used are ion-exchange resins based on the copolymerization of either polystyrene or polyacrylate and divinylbenzene. The brands of synthetic resin-based anion exchangers used in the present invention: Anion exchange resin 17-8СС, Anionite Purolite А520Е, Lewatit S 6328 А (based on styrene-divinylbenzene copolymer), “Lewatit M500”, “Lewatit MonoPlus MK 51”, “Lewatit MonoPlus MK 68” ”, Purolite C150E, Purolite A-860 (macroporous strongly basic acrylate-based anion exchange resin), anion exchange resin sulfonated styrene-divinylbenzene anion exchange resin. The listed anion exchangers impregnated with the above electrolyte compositions showed a positive result when polishing blades of alloy steels.

During processing, the vibrational movement of granules with a frequency of 50 ... 400 Hz was used: 40 Hz (N.R.), 50 Hz (U.R.), 100 Hz (U.R.), 150 Hz (U.R. ), 250 Hz (U.R.), 300 Hz (U.R.), 350 Hz (U.R.), 400 Hz (U.R.), 450 Hz (N.R.) and amplitude 1, 0 to 6.0 mm (0.5 mm - N.R., 1.0 mm - U.R., 2.0 mm - U.R., 3.0 mm - U.R., 4.0 mm - U.R., 5.0 mm - U.R., 6.0 mm - U.R., 7.0 mm - N.R.).

In pulse mode with polarity reversal:

- pulse frequency range from 20 to 100 Hz: 15 Hz (N.R.), 20 Hz (U.R.), 40 Hz (U.R.), 60 Hz (U.R.), 80 Hz (U .R.), 100 Hz (U.R.), 120 Hz (N.R.)

- pulse period from 50 μs to 10 μs ,: 60 μs (N.R.), 50 μs (U.R.), 40 μs (U.R.), 30 μs (U.R.), 20 μs ( U.R.), 10 μs (U.R.), 5 μs (N.R.);

- the amplitude of the current of positive polarity during the +50 A pulse and their duration 0.4 μs to 0.8 μs: 0.2 μs (N.R.), 0.4 μs (U.R.), 0.6 μs (U.R.), 0.8 μs (U.R.), 10.0 μs (N.R.);

- when the amplitude of the current of negative polarity during the pulse is 20 A, and their duration is 0.2 μs to 0.4 μs, 0.1 μs (N.R.), 0.2 μs (U.R.), 0, 3 μs (U.R.), 0.4 μs (U.R.), 0.5 μs (N.R.);

- with a rectangular shape of the output current pulses (U.R.),

- and the duration of pauses between pulses from 49.6 μs to 9.2 μs - (U.R.) out of range - (N.R.).

The value of the deviation from the edges was taken equal to from 0.5 to 4 mm - (U.R.). (when the deviation is less than 0.5 mm - (N.R.), if the deviation from the edges is exceeded more than 4 mm - (N.R.))

Use as gaskets of metal plates with a thickness of 0.3 to 2 mm - (U.R.).

The use of non-metal plates as spacers with a thickness of 0.3 to 2 mm while ensuring electrical contact between the torsions in the package is (U.R.).

Use as screens metal plates with a thickness of 6 to 10 mm- (U.R.).

Coverage of screens, from the side of contact with torsion bars with a layer of dielectric material with a thickness of 1 to 4 mm - (U.R.).

Used electrolytes for impregnation of granules made of anion exchangers:

1) NH ₄ F, concentration from 6 to 24 g / l (going beyond NH ₄ F concentrations from 6 to 24 g / l gives a negative result);

2) NaF, concentration from 4 to 18 g / l, (going beyond the concentration range from 4 to 18 g / l gives a negative result);

3) KF with a concentration of 35 to 55 g / l, (going beyond the concentration range of 35 to 55 g / l gives a negative result);

4) mixtures of NH ₄ F and KF with an NH ₄ F content of from 5 to 15 g / l (going beyond the limits of NH ₄ F concentrations from 5 to 15 g / l gives a negative result) and KF from 30 to 50 g / l (going beyond KF concentrations from 30 to 50 g / l gives a negative result),

5) a mixture of NaF and KF with a NaF content of from 3 to 14 g / l (going beyond NaF concentrations from 3 to 14 g / l gives a negative result), and KF from 35 to 60 g / l (yield KF concentration limits - from 35 to 60 g / l, gives a negative result),

6) a mixture of NH ₄ F and NaF with an NH ₄ F content of from 4 to 12 g / l (going beyond NH ₄ F concentrations from 4 to 12 g / l gives a negative result) and KF from 35 to 55 g / l (going beyond the concentration of KF - from 35 to 55 g / l, gives a negative result),

7) mixtures of NH ₄ F, NaF and KF with an NH ₄ F content of from 3 to 9 g / l (going beyond NH ₄ F concentrations from 3 to 9 g / l gives a negative result), and KF from 20 up to 30 g / l, (going beyond KF concentrations from 20 to 30 g / l gives a negative result), and NaF from 10 to 25 g / l (going beyond NaF concentrations from 10 to 25 g / l gives a negative result)

8) mixtures of NH ₄ F and HF with an NH ₄ F content of from 5 to 15 g / l (going beyond NH ₄ F concentrations from 5 to 15 g / l gives a negative result), and HF from 3 to 5 g / l (going beyond HF concentrations from 3 to 5 g / l, gives a negative result),

9) from 8 to 14% aqueous NaNO ₃ solution (going beyond the limits of NaNO ₃ concentrations from 8 to 14% gives a negative result).

Compared with the used mechanical processing method (RF patent No. 2560814), the torsion bar is rounded off during processing according to the proposed method, the productivity of the processing process increases by an average of 2.5-3 times, and the average surface roughness from Ra 0.65 .. 0.45 μm, for the proposed method it improves to Ra 0.03. 0.02 μm, the resource increases from 1.3 to 1.6 times.

Thus, the use of the essential features given in the formula of the invention ensures the achievement of the technical result set in the invention - improving the quality of polishing and rounding of the edges of the plate torsion bar, as well as improving the operational characteristics of the torsion bar while reducing the complexity of the processing process.

Claims (11)

1. The method of processing the edges of the plate torsion of the rotor of the helicopter, including assembling the torsion bars in the package with the combination of their contours and processing the edges in the package, characterized in that the assembly of the torsion bars in the package is made through flat gaskets repeating the torsion bar with a deviation from the edges by an amount that provides free access to the processing of the edges of the torsion bars, with overlapping screens repeating the configuration and location of the said gaskets on the outer surfaces of the extreme torsion bars of the package, immersing the torsion bar package in the environment of granules made of anion exchangers impregnated with an electrolyte solution providing electrical conductivity of said granules and ionic ablation of a metal to remove microprotrusions from its surface, contacting the processed edges of the torsion bar with said granules, bringing said granules into vibrational motion, ensuring uniform washing of granules of the edges of the torsion bar, feeding on torsion and granules of electric potential, providing ion ablation of metal from the processed surface of the edges, their polishing and rounding the edges in the medium of said granules to obtain a given surface roughness and a given radius of rounding of the torsion edges, said granules being reciprocated with respect to the machined edges of the torsion bar. 2. The method according to p. 1, characterized in that metal plates are used as gaskets, and metal plates are used as screens, which are coated on the contact side with torsion bars by a layer of dielectric material, the value of the mentioned deviation from the edges being taken from 0.5 to 4 mm. 3. The method according to p. 1, characterized in that the plates and screens use plates of dielectric material, and the magnitude of the mentioned deviation from the edges is taken equal to from 0.5 to 4 mm 4. The method according to p. 1, characterized in that the ion exchange resins obtained on the basis of copolymerization of either polystyrene or polyacrylate and divinylbenzene are used as the anion exchangers of the granules, the granule sizes being selected from the range from 0.1 to 0.8 mm. 5. The method according to p. 1, characterized in that the electropolishing with granules is carried out by applying a positive electric potential to the torsion, and a negative electric potential from 25 to 35 V. 6. The method according to p. 1, characterized in that the polishing of the granules is carried out in a pulsed mode with a change in polarity, with a pulse frequency range of 20 to 100 Hz, a pulse period of 50 μs to 10 μs, and a current amplitude of positive polarity during a pulse + 50 A and their duration 0.4 to 0.8 μs, with a current amplitude of negative polarity during a pulse - 20 A, and their duration 0.2 to 0.4 μs, with a rectangular shape of the output current pulses and the duration of pauses between pulses from 49.6 μs to 9.2 μs. 7. The method according to any one of paragraphs. 1-6, characterized in that they use torsion made of alloy steel, and as electrolytes for impregnation of the said granules from anion exchangers one of the following aqueous solutions is used, including: NH ₄ F, concentration from 6 to 24 g / l, or NaF with a concentration of 4 to 18 g / l, or KF, a concentration of 35 to 55 g / l, or a mixture of NH ₄ F and KF with an NH ₄ F content of 5 to 15 g / l and KF of 30 to 50 g / l or a mixture of NaF and KF with a NaF content of 3 to 14 g / L and KF from 35 to 60 g / l, or a mixture of NH ₄ F and NaF with a NH ₄ F content of 4 to 12 g / L and KF from 35 to 55 g / l, or a mixture of NH ₄ F, NaF and KF with an NH ₄ F content of 3 to 9 g / l, KF from 20 to 30 g / l and NaF from 10 to 25 g / l, or mixtures of NH ₄ F and HF with an NH ₄ F content of 5 to 15 g / l and HF from 3 to 5 g / l, or NaNO ₃ concentration from 8 to 14%, or using an electrolyte composition, wt.%: (NH ₄ ) ₂ SO ₄ - 5, Trilon B - 0.8; or an electrolyte containing sulfuric and phosphoric acid, a block copolymer of ethylene oxide and propylene and the sodium salt of sulfonated butyl oleate in the following ratio, wt.%: sulfuric acid 10-30 orthophosphoric acid 40-80 block copolymer of ethylene oxide and propylene 0.05-1.1 sulfonated butyl oleate sodium 0.01-0.05 water rest 8. The method according to any one of paragraphs. 1-6, characterized in that after rounding the edges of the torsion bars the package is disassembled and each of the torsion bars is polished in the medium of said granules to obtain a given surface roughness. 9. A device for processing the edges of the plate torsion of the rotor of the helicopter, consisting of a holder of a package of plate parts and means for processing their edges, characterized in that the holder of the package is made in the form of two flat screens with a clamping device that provides clamping through the said screens of the torsion bars assembled through laying in a package, and screens and laying repeat the torsion contour with a deviation from the edges by an amount providing free access to the processing of the edges of the torsion bars, and the means for processing to the torsion bar is made in the form of a container with electrically conductive granules, which ensures complete immersion of the torsion packet in the granule medium, the container being provided with current leads to the container and to the electrodes insulated from the container, a vibrator providing vibrational movement of the said granules with a frequency of 50-400 Hz, and a device providing reciprocating movement and rotation of the torsion package. 10. The device according to p. 9, characterized in that metal plates with a thickness of 0.3 to 2 mm are used as gaskets, and metal plates with a thickness of 6 to 10 mm, coated from the side of the torsion with a layer of dielectric material, are used as screens thickness from 1 to 4 mm, equipped with stiffeners and contact points for the clamping device, and the magnitude of the mentioned deviation of the screens and gaskets from the edges is taken equal to from 0.5 to 4 mm.

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