Composition for obtaining coating for reducing mechanical failures of high-speed electric machine rotor
SUBSTANCE: composition for obtaining coating for reducing mechanical loss of high-speed electric machine rotor relates to hybrid organic-inorganic nanocomposite coatings, capable of reducing mechanical loss of high-speed electric machine rotor in cooling gaseous medium. Composition includes sol with silicate constituent based on tetraethoxysilane or methyltriethoxysilane water-alcohol solution and additionally contains modifying additive in form of compound, possessing pyro- and/or piezoelectric properties with size of particles and their aggregates 50-100 nm, with the following component ratio (wt %): sol with silicate constituent - 96-99; modifying additive - 1-4.
EFFECT: application of methyltriethoxysilane in sol composition provides adhesion with stainless steel without high-temperature processing and 11-12 class of surface roughness; application of tourmaline piezoelectric crystals as modifying additive in form of alcohol suspension or crystal powder provides antifriction properties of coating.
1 dwg, 3 ex
The invention relates to a hybrid organic-inorganic nanocomposite coatings, particularly coatings, formed on the basis of amoxicillindosage Zola, which give some useful properties, such as the ability to reduce friction surface of the rotor rotating with high speed in the cooling gaseous medium. The composition may be used in the form of a surface coating of a high speed rotor to reduce mechanical losses and heating.
There are various formulations of anti-friction coatings, which are applied to the solid contact surface to reduce the coefficient of friction and wear of the contact surfaces of friction and ways of their application.
A method of obtaining a polymer antifriction coating on the surface of the product, including consistently clean a given surface cleaning agent, drying the cleaned surface, the antifriction coating composition solution organofluorine surfactant - epilame - performanceoriented or perfluorinated compounds polyalkylated by immersing the product in this solution, the heat treatment of the coating, characterized in that the cleaning and drying the surface of the product is carried out in the first tank, and cleaning is performed by immersing the product in eating the beard with a cleansing agent with ultrasound, the drying is carried out under the action of infrared rays, and the application of anti-friction composition and heat treatment of the coating carried out in the second capacity, and the stage of the antifriction coating composition is carried out by immersing the product in a container with anti-friction composition with a temperature of 50-60°C when exposed to ultrasound with a frequency of 18-22 kHz, heat treatment of the coating is carried out using an infrared emitter, see RF patent №2280051.
A method of obtaining anti-friction coating on the contacting surfaces mainly plunger of the fuel high-pressure pumps by applying anti-friction composition containing organofluorine compound, characterized in that the composition additionally enter the dispersant is a nonionic surfactant, and as organofluorine compounds use performoperation with a molecular mass of 1400-5600 in the following ratio, wt. %: performoperation - 65-75, dispersant - 25-35, see RF patent №2391369.
Currently, to reduce mechanical losses to the friction surface of the rotor grind, ensuring 11-12 class of roughness. Further reduction of friction losses is possible using other effects.
Known polysiloxane composition, which includes the Sol based on water-alcohol is the first solution of tetraethoxysilane with the addition of an inorganic acid, for example, nitric or hydrochloric, and metal salts, such as antimony, manganese, and others, see Shilova O. A. nanoscale Silicate films obtained by the Sol-gel method, for planar fabrication technology of semiconductor sensors. // Physics and chemistry of glass. So 31. No. 2. 2005. C. 270-293. The article is an overview of the Sol-gel process for fabricating films of colloidal solution on the basis of the water-alcohol solution of tetraethoxysilane with the addition of acid and metal salts.
This composition Zola used to form films on the materials of electronic technology by centrifugation (similar to application of the photoresist in semiconductor technology) with a subsequent heat treatment for the manufacture of semiconductor gas sensors based on SnO2.
Known composition to obtain a coating to reduce mechanical losses of high-speed rotor of the electric machine, see Kruchinina I. Y. and other Problematic issues of creation of a high-speed mini-turbine generators and their solutions, Information management systems, 2012, No. 4, S. 30, column 1, paragraph 1 from below.
This composition was chosen as the prototype of the claimed technical solution.
Known composition is not sufficiently effective to receive anti-friction coatings can reduce the friction loss of air in the micro-turbines, because breaet the required properties (strength, adhesion to the substrate) only after heat treatment at temperatures of 250-300°C and above. Such heat treatment is not valid for a rotor of an electric machine, because there is a possibility of demagnetization of the individual parts of the rotor.
The objective of the invention is to provide a composition to obtain a coating formed on the basis of silica sols and having the ability to reduce mechanical losses friction surface speed of the rotor about the environment.
The essence of the invention as a technical solution is expressed in the following essential features.
Composition to obtain a coating to reduce mechanical losses of high-speed rotor of the electric machine, which includes a silica Sol component on the basis of the water-alcohol solution of tetraethoxysilane or methyltriethoxysilane with the addition of an inorganic acid and a modifying additive in the form of compounds with pyro and/or piezoelectric properties, selected from boron silicates and of barium titanate, with the size of the particles and their aggregates of 50-100 nm in the following ratio of components (weight%): Sol with a silica component, 96-99; modifying additive - 1-4.
Direct technical result achieved in the implementation of the essential features of the claimed invention, what is it, the presence in the composition of the crystal chips pyro - or of a piezoelectric material leads to ionization of the surrounding space at room temperature, which in turn leads to anti-friction effect in relation to air, i.e., to improve the aerodynamic properties of objects, which caused the claimed composition.
Use as part of Zola methyltriethoxysilane provides adhesion to stainless steel without high temperature processing and grades 11-12 surface roughness.
When used as modifying additives of boron crystals of silicates (tourmaline) in the alcohol suspension or crystal powder, leads to the fact that the coating of such a composition has anti-friction properties due to the charge on the coating surface. This charge is able to create an additional layer between the surface of the object and the environment. Piezoelectric properties of tourmaline used in hydrostatic pressure sensors, acoustic electronics, optics and sophisticated electronics.
The lower limit for the introduction of modifying additives 0.01 g is determined by the reduction in anti-friction properties. The introduction of modifying additives in the amount of more than 0.4 g impractical, as the floor crumbles and loses mechanical strength.
the Claimed composition can be prepared as follows.
1. Preparation of silicate component Zola: to 2 ml MTAS poured to 1.14 ml of ethanol and added dropwise to 0.36 0.1 M hydrochloric acid and intensively stirred for 1 hour. The molar ratio of the components in the ashes 1:0,535:1,25:0,002. The percentage: 28,08:58,18:13,7:0,04.
2. Introduction in the resulting Sol modifying additives: take away the hinge Zola equal to 2 ml, and mixed with an alcoholic suspension of a powder of tourmaline (10 ml of ethanol and 0.2 g of tourmaline). The result is a muddy opalescent Sol.
3. Aging Sol: Sol stand before you can use within 2 hours in the air (in closed containers) at room temperature.
4. The coating on the surface is carried out by sputtering.
5. Drying the formed coating: in a drying Cabinet at a temperature of 65-80°C.
Obtaining a composition containing 0.2 g of barium titanate particle size of 60-80 nm the Composition is prepared analogously to example 1. Source piezoelectricity properties uses of barium titanate. The molar ratio of components in the resulting ash following: 1:0,195:0,54:0,0007:0,029 Percentage: 47,34:35,67:10:of 6.96 (ethyl alcohol, METEOS, water, inorganic acid and barium titanate).
Analogously to example 1. As alkoxysilane used tetraethoxysilane in the same Pro is orlah.
1. Preparation of silicate component Zola: 2,24 ml TEOS poured to 1.14 ml of ethanol and added dropwise to 0.36 0.1 M hydrochloric acid and intensively stirred for 1 hour. The molar ratio of the components in the ashes 1:0,536:1,25:0,002. Percentage: 25,55:61,94:12,47:0,04 (ethanol, TEOS, water and inorganic acid).
2. Introduction in the resulting Sol modifying additives: take away the hinge Zola equal to 2 ml and mixed with an alcoholic suspension of a powder of barium titanate (10 ml of ethanol and 0.2 g of barium titanate). The result is a muddy opalescent Sol.
3. Aging Sol: Sol stand before using for 2 hours in air (in closed containers) at room temperature
4. The coating on the surface is carried out by sputtering.
5. Drying the formed coating: in a drying Cabinet at a temperature of 65-80°C.
Industrial applicability of the claimed invention is confirmed by the results of experiments on model machine when the rotor speed 18000 min-1. The rotor had been declared a coating of barium titanate. When the temperature of the shaft 30 to 50°C was observed a significant decrease in the total mechanical losses.
Declared organosilicate composition is easy to prepare and convenient in operation. Production this is oppozitsii can be implemented industrially in batch production using well-known technical and technological resources.
Composition to obtain a coating to reduce mechanical losses of high-speed rotor of the electric machine, which includes a silica Sol component on the basis of the water-alcohol solution of tetraethoxysilane or methyltriethoxysilane with the addition of an inorganic acid and a modifying additive in the form of compounds with pyro and/or piezoelectric properties, selected from boron silicates and of barium titanate with the size of the particles and their aggregates of 50-100 nm, in the following ratio, wt. %: silica Sol component - 96-99; modifying additive - 1-4.
SUBSTANCE: invention is related to the area of electric engineering and referred to winding insulation fabrication technique for electrical machines, mainly for traction motor armatures - direct-current machines. During impregnation with compound having viscosity of 70-100 s as per B3-4 dents and irregularities occur at bands. This is due to the fact that at high vacuum ≤1 mbar, upon vacuum degassing, compound filling and applying high pressure, there's no sufficient time for the compound to be penetrated to the winding under the band, in result pressure drop occurs between the external surface of the band and internal winding, additional pressurization of coils supports takes place thus leading to occurrence of dents and irregularities at the band surface. Dents at the band are no accepted as in this way they are spots for accumulation of dust, dirt, moisture, etc. According to the claimed technique the armature heated up to impregnation temperature is placed into the impregnating vessel and subjected to vacuum degassing; then the impregnating compound is delivered under vacuum. At that, according to the invention, in order to eliminate the above defects and to achieve the above technical result pressure is delivered gradually up to 6-8 bar during 15 minutes.
EFFECT: technical result attained due to this invention use lies in increase of electrophysical characteristics of insulation, water- and moisture-resistance of windings.
2 cl, 1 tbl
SUBSTANCE: invention relates to the field of electric engineering and electric machine building, in particular, to manufacturing and repair of electric machines, for instance, windings of traction electric machines (TEM) of locomotives and multiple-unit rolling stock. According to the proposed selective method for drying of moist and impregnated insulation, drying of insulation of windings in an evenly rotating anchor of TEM is carried out by long-wave pulse ceramic infrared (IR) emitters, arranged along the length of the active part of the anchor, and also at the side of its front part. The proposed device for realisation of this method consists of a stand (1) with an attached variable-frequency asynchronous electric drive (3) and a rack (2), on which long-wave pulse ceramic IR-emitters are installed. The TEM anchor is rotated, and simultaneously the moist or varnish-(compound-)impregnated insulation of the front and active parts of the anchor winding in the rotating TEM is heated to the temperature of 100 … 120° C with the help of the specified IR-radiators, which provides for drying of insulation.
EFFECT: technical result achieved when using the proposed invention consists in provision of even heating of windings insulation along the entire area of the anchor, which increases quality of drying of TEM anchor winding insulation with simultaneous reduction of power inputs and time for technological process of insulating drying.
4 cl, 2 dwg
SUBSTANCE: invention is related to the field of electric engineering, and namely to non-destructive quality control procedures for electrical products, in particular, to impregnation of windings of electrical machines. According to the suggested method for determination of impregnation coefficient for electrical machine windings impregnated by cured polymer composition capacitance values Ccbi and Ccui in regard to the ground are measured for each electrical machine winding in the batch before and upon impregnation by the polymer composition and drying. Then, upon impregnation and drying of windings temperature of each winding T1ui is measured and through the wire of each tested winding stabilised direct current I0 is passed and its values is selected depending on section area S of the winding wire strand within the range of maximum current density permitted for the material of the winding wire from jmin up to jmax within the range of values jminS ≤I0≤jmaxS. At that the above selected current I0 is passed through the winding during a certain period of time t0 and voltage drop is measured at the winding U1i at the moment of stabilised current delivery to it and voltage drop at the winding U2i at the above period of time t0. Upon the above operations according to measurement results the impregnation coefficient Kic is determined for each tested winding in the near-body cavities and impregnation coefficient Ktt of turn-to-turn cavities in the windings as per the following formulas:
EFFECT: simplification of the method due to avoidance of measuring capacity in regard to the ground for one random winding and self-capacitance before impregnation, dipping of the above winding into impregnating liquid with the known dielectric capacitivity and measuring of this winding capacity in regard to the ground and self-capacitance again with the winding placed in the impregnating liquid as well as die to avoidance of double measurements of self-capacitance for each of the tested winding before and upon impregnation, improvement of accuracy because the value of impregnation coefficient does not depend on relative position of turns in the slot, as well as increase in information content of control because this method allows to determine distribution of the impregnation composition inside the winding and impregnation coefficients for near-body and turn-to-turn cavities of windings.
1 tbl, 2 dwg
SUBSTANCE: batch of samples is prepared preliminary for an impregnating compound with different degree of dryness for each sample and dependency of the dielectric permittivity on frequency of the electromagnetic field is defined for the above samples. According to the defined dependencies two measurement frequencies are selected, one frequency f1 lies in a dispersion region of the non-hardened insulating impregnating compound while the other frequency f2 lies in an optical region of the non-hardened insulating impregnating compound. Using the defined frequency dependencies for the samples dryness and the dielectric permeability curves for the impregnating compound are plotted as
EFFECT: excluding necessity of self-capacitance measurements for windings at three frequencies with use of reference inductance with simultaneous and essential simplifying of measurements due to exclusion of manufacture and use for the purpose of control of such elements as a current stabiliser, a heating time metre and metre of windings temperature increment in heating process.
1 tbl, 4 dwg asd - as
SUBSTANCE: when the winding is heated up to the preset temperature before impregnation current pulses with an amplitude within the range of (10-50)A and a pulse length of (0.5-10)s are supplied to the winding. Pulse repetition frequency is in the range of (5-10)Hz. Simultaneously with supply of the above pulses the infrared oscillator is connected to the magnet core of the winding. At that the frequency of sound oscillations of the infrasound source are varied constantly and cyclically within the frequency band from 0.5 kHz up to 10 kHz and back. When impregnation is over the infrasound frequency generator is disconnected from the magnet core, the source of current pulses is disconnected from the winding, direct or alternating heating current is supplied to the winding and by means of this current the impregnated winding is heated up to the polymerisation temperature of the impregnating compound and then the winding is dried until the impregnating compound is hardened completely.
EFFECT: reduction of impregnation time per 1,8 times and increase in impregnation coefficient per 1,8 times with simultaneous triple reduction of impregnation coefficient spread for each winding.
SUBSTANCE: spectral-oscillating method for impregnation of the end winding insulation of rotating electric machines consists of three successive steps: 1) moisture removal by infrared (IR) heating of the end winding insulation before impregnation at the maximum allowable temperature for this class of insulation; 2) application of impregnating mixture at the end windings by automatic high-pressure sprayers; 3) transportation of the impregnating mixture into the depth of the end winding insulation by short-wave and medium-wave pulse ceramic converters of IR radiation. At that moisture removal from the end winding insulation before impregnation and transportation of the impregnating mixture into the depth of the end winding insulation is performed in spectral-oscillating modes of energy supply with cyclic alternation of short-wave and medium-wave IR radiation.
EFFECT: multiple increase in quality of impregnation process with simultaneous reduction of impregnation time in 7-10 times and provision 2- or 3-time effect of energy saving.
2 cl, 2 dwg
SUBSTANCE: invention relates to electric engineering and namely to method for determination of impregnation coefficient for coils of electrical machines connected in star with insulated neutral. According to the method for determination of impregnation coefficient for coils of electrical machines characterising degree of filling by impregnating compound of coil cavities for each coil in this batch electrical parameters are measured before impregnation and after impregnation and drying; among selected electrical parameters there are capacities of two phases of star-connected coil, which are measured in turn before impregnation CBI12, CBI13, CBI23 and after impregnation CAI12, CAI13, CAI23 in regard to the ground; thereafter by measurement results impregnation coefficient is defined for each two phases KIMP12, KIMP13, KIMP23 by mathematical relationship, then impregnation coefficients are defined for each phase of coil by mathematical relationships.
EFFECT: possibility to define the averaged impregnation coefficient and distribution of impregnating compound among phases of coil thus increasing informativity and accuracy of control.
2 tbl, 3 dwg
SUBSTANCE: method of impregnating the multi-winding coil of an electrical machine involves feeding to the front parts of the coil a thin jet of a impregnating composition from a nozzle to the heated front part of the coil and rotating the jet along the front part of the coil. Before impregnation, fine ferromagnetic filler, which is pre-disintegrated, is added to the impregnating composition. The impregnating composition is mixed with the ground ferromagnetic filler; the obtained mixture is stirred and poured into the impregnating apparatus. Before impregnation, coil data are used to calculate the maximum mass of the impregnating composition mim, which can be accommodated in the cavities of each of the same-type coils during impregnation. An electrode is inserted into the nozzle and potential is applied across the electrode. The process of impregnating each of same-type coils is then carried out. During the impregnation process, particles of the impregnating mixture of the compound with fine ferromagnetic powder are electrostatically charged. A jet is formed. Final compounding of the impregnating mixture that has penetrated the coil is then carried out.
EFFECT: method increases the impregnation coefficient of the coils by 1,55 times on average and improves stability thereof from coil to coil.
SUBSTANCE: impregnating composition is fed from a container in form of a jet rotating along front parts of the windings, wherein the jet of the impregnating composition is charged with an electrostatic charge by passing it along the surface of a high-voltage electrode; the winding conductor is earthed and the jet is rotated by passing it through an inductor which generates a rotating magnetic field. The sign of the electrostatic charge of the jet is periodically varied to the opposite sign by transmitting inverted high-voltage pulses to the high-voltage electrode, wherein the duration of each pulse is equal to the period of rotation of the jet along the front part.
EFFECT: method increases efficiency of impregnating windings by 1,3-1,4 times.
SUBSTANCE: electric insulation material impregnated with a heat-resistant binder is applied onto a winding, the winding is installed on a core, heated and impregnated under vacuum and pressure, besides, the main insulation of the winding is first impregnated with polyetherimide compound of H heat-resistance class, and a monoblock is impregnated with epoxide compound of F heat-resistance class with subsequent hardening. In particular, during method realisation, a mica-containing tape is applied onto a pole coil, and the tape is impregnated with polyetherimide compound of H heat-resistance class, the coil is placed on the pole previously insulated with electric insulation material. The monoblock is heated to temperature providing for compound migration inside the insulation, is placed into an impregnation autoclave and impregnated with compound of the heat resistance class F under vacuum and pressure. After draining of compound excess the monoblock is placed into a thermostat and hardened at the temperature providing for simultaneous hardening of the compound in the tape and the impregnation compound in the winding. Main insulation exposed to maximum thermal loads corresponds to the heat resistance class H. The gap between the coil and the pole is impregnated with compound of heat resistance class F, which has high mechanical strength, heat conductivity and heat resistance up to the temperature of heat class resistance H.
EFFECT: higher force of pressing of windings in electric machines of heat resistance class H.
SUBSTANCE: in the method for insulation of slots of the magnet cores in micromotor stators based on charging of electroinsulating material particles with electric charge and their precipitation into slots under action of the electric field, the new development lies in placement of the armature magnet cores in the centre of an elastic cylindrical dielectric cup that covers hermetically the outer surface of the armature magnet core, installation of two electrodes at a distance of 20-30 mm from end walls of the armature magnet core, filling of the above cup with electrophoretic compound with the following ratio of components (in mg/l): varnish PE-939 of C mark - (510÷255), 1% - liquid ammonia 1% - NH4OH - (130÷190), ethyl cellosolve - C4H10O2 - (120÷175), diethylene oxide (C4H8O2) - the rest. Positive potential from the direct current source is supplied to the magnet core and negative potential from the above source is supplied to electrodes and at current density within the range of 2-10 mA/cm2,electrophoretic precipitation of the film former is made to the slots, to end surfaces and a shaft of the magnet core armature within the period of rime defined as per the formula
EFFECT: increase of breakdown voltage of the film 1,4 timers more than the breakdown voltage of the film obtained by the prototype method, receipt of higher, a sequence higher, adhesive and mechanical properties of the film with simultaneous reduction of labour intensity during slots isolation per 38 times.
SUBSTANCE: saturated mica-containing belts with binder fluidity of 20% are placed on bar windings at temperature of 20°C and pressure of 10 kgf/ cm2 and binder gelling time of at least 10 minutes at 130°C. Press boards are placed on groove portions and flexible metal boards are placed on front portions. The windings are tied with jacketing tape (which simultaneously soaks excess saturating composition), after which a polyethylene or polypropylene sleeve is worn onto the bars. The sleeve is sealed. A set of bars prepared in this manner is placed on a loading frame and a connecting piece from each of the bars is connected to a vacuum collector. When the vacuum is turned on, air-tightness of the packed bars is checked. The frame is then put into a container in which air pressure of 8-10 kgf/cm2 is created at room temperature. The container is then heated to 150-160°C and held at said pressure and temperature for 6-10 hours.
EFFECT: design of bar windings of electric machines of heat-resistance class H with improved electrical properties and stable dimensions on thickness.
2 ex, 1 tbl
SUBSTANCE: there proposed is the device for forming of rotor isolated conductor by means of application of isolating material on one side of flat electric conductor at controlled heating and mechanic pressure. Rotor conductor serves for assembling in a unit the rotating electric machine rotor such as alternating current generator. The device contains modules that provide simple movement to production environment and efficient use of production space. Also the corresponding method of forming of rotor isolated conductors was revealed.
EFFECT: reduction of labour intensiveness of pack treatment operations and elimination of expensive part retreatment, increase of labour and equipment efficient use.
20 cl, 8 dwg
FIELD: electrical engineering.
SUBSTANCE: coils are wound on the frame by copper wire coated with polyethylene lacquer. Coils surface is insulated by a layer of insulating tapes. Isoflex spacers are arranged between layers of turns. Note that coil surface insulation is made by one layer of tape "ЛЭС" and tape "ГИП-ТС-Пл", and six layers of glass-mica tape "ЛСЭП-934-ТПл". Then, coils are impregnated with thermosetting lacquer in vacuum-pressurisation procedure. Coils fitted in stator, the coils are additionally coated by isolation enamel "ГФ92ХС" or insulating lacquer "БТ-99".
EFFECT: higher reliability, longer life.
FIELD: electrical engineering.
SUBSTANCE: proposed invention is concerned with characteristic features of ground insulation capable of sustaining voltages higher than 4 kV, best of all 13.8 kV or higher still used for dynamoelectric machines. Machine winding insulation or conductor ground insulation has two layers. First internal layer covers conductor and has first predetermined thickness and first predetermined dielectric constant; second insulation layer has second predetermined thickness and second predetermined dielectric constant lower than that of first one. First and second insulation layers have mica paper strip, different type of mica being used for each strip with the result that pattern of electric field across ground insulation at first-to-second layer transfer point abruptly rises causing occurrence of electric field close to conductor whose strength is maximal and lower than that of known insulation systems. In this way maximal value of local electric field pattern within ground insulation reduces.
EFFECT: enhanced service life and reduced thickness of insulation.
15 cl, 7 dwg
SUBSTANCE: invention relates to composition for superficial processing of surfaces in form of liquid agent for superficial processing, such as UF-solidified filler-containing vanish. Invention also relates to application of said composition for preliminary processing of surfaces and/or their edges of flat-shape elements. Agent for surface processing contains film-forming resin acryl-based composition and filler (3), with said filler including disperse material, selected from common salt, chalk (CaCO3), powder, glass particles or granules. Filler has size of particles smaller than 400 mcm. Agent for surface processing is used mainly for application on chamfers and edges of flat-shape elements from solid wood, laminated wood-based products, such as veneered panels and chipboard panels, panels of medium density and panels from mineral wool and plaster.
EFFECT: preliminary processing of surface with agent makes it possible to create smooth surface, which has good adhesion for the following decoration work, ie prolong service term of instruments, used for the following panel processing.
11 cl, 3 dwg