Device for balancing of high-speed rotor of a turbomachine
The device is designed for high-speed turbomachines (turbopump assemblies rocket engines, turbochargers, aircraft gas turbine engines). The device consists of a body and a lid, which is made of the internal reference cylindrical surface and the inner support ends. On the outer side in the housing and the cover is cylindrical mounting elements. The housing and the cover are connected by a connecting planes passing through the axis of the internal reference cylindrical surfaces. Balancing the rotor in its bearings mounted on the supporting cylindrical surfaces between the inner support ends. Between the inner bearing end face and the end face of the bearing has an elastic axial element. The housing and the cover are installed in the outer casing comprising a lower and an upper part that is connected on the mating surfaces. In an external enclosure coaxial cylindrical mounting body and the cover are external cylindrical mounting elements. In the housing, the cover and the outer casing is made channels for supplying and discharging lubricant. In an external enclosure installed sensors deflection of the rotor. Low-frequency balancing Roto is isolobodon rotors by eliminating axial and radial clearances in the bearings, secure attachment of the rotor and to improve the lubrication of its bearings in the high-frequency balancing. 4 C.p. f-crystals, 2 Il. The invention relates to mechanical engineering and can be used in high-speed turbomachines (turbopump units rocket engines, turbochargers, aircraft gas turbine engines).High technical characteristics of modern turbomachines can be achieved at high frequencies of rotation of the rotors. Vibrations caused by the operation of high-speed machines, create additional loads on structures, reducing the service life of the machines. In addition, vibrations have an adverse effect on the human body. One of the causes vibration of the turbomachine is the unbalance of the rotor. To reduce the unbalance of rotors produce their balance by correcting the mass. Ensuring a minimum degree of unbalance of rotors is an important task in all phases of technology development.The rotors may be subjected to low-frequency or high-frequency balancing. Low-frequency balancing is performed when the rotational speed of the rotor is substantially lower operating speed and applies DL the s spins. High-speed balancing is performed over the entire range of operating frequencies of the rotor and is used for high-speed flexible rotors, the working speed which is greater than the first critical speed. In relation to the turbopump units LRE high-speed balancing is used for rotors operating at speeds over 30,000 rpm In the high-frequency balancing the rotor is installed in the device (the device), which is fixed in the supports of the balancing machine (stand). The residual unbalance of the rotor when the balancing is largely determined by the applied device for balancing.A device for balancing a rotor, comprising a housing and support. Supports mounted on the connecting plane of the housing. The body is made of the internal reference of the cylindrical and end surfaces on which you will install your ball balancing the rotor. The rotor is mounted in the housing supports. On the casing is placed a cylindrical mounting elements, which he relies in support of the balancing machine. The installation elements are perpendicular to the axis of the cylindrical support surfaces (Leviticus M device has the following disadvantages.Balancing the rotor can make a precessional movement within the radial clearance and axial vibrations within the axial clearance in the bearings. In the precessional motion of the rotor has an imbalance equal to the product of the mass of the rotor on the value of radial clearance in the bearings. Axial vibrations of the rotor increases the residual imbalance. These imbalances cannot be eliminated by correction of the rotor. During operation of the turbomachine unresolved imbalance creates dynamic loads on the rotor and its bearings, which increases vibroactivity and reduces the durability of the machine.In the process of high-frequency balancing before adjusting his weight on the ball of the rotor can influence significant dynamic radial load imbalance. These loads are transmitted to the housing, the bearings and cylindrical mounting elements of the device. In the specified device is not reliable fastening of the rotor under the action of dynamic radial load imbalance. Not also ensures secure mounting and the device on the balancing machine. As a result of this high speed, the rotor cannot be ambulanceroid within the working range of custservice can only be achieved when the liquid lubricant. The known device does not contain structural elements that provide the liquid lubricant ball bearings, which limits the rotational speed of the rotor when it is balanced.The device no sensor deflections of the rotor, which prevents in the process of high-frequency balancing to minimize deflections of the rotor.The task of the invention is to remedy these disadvantages and improve the quality of balancing of high-speed rotors by eliminating axial and radial clearances in the bearings, and secure attachment of the rotor and improve lubrication of its bearings in the high-frequency balancing.The problem is solved in that the device for balancing of high-speed rotor of a turbomachine, comprising a housing with an inner cylindrical support surfaces and ends, a connecting plane which has a support, and a cylindrical mounting elements according to the invention supports are made in the form of a cover, forming together with the case of General internal reference cylindrical surface and end faces, and a cylindrical mounting elements are made in the housing and the cover in alignment with their internal reference cylindrical-poverhnostnym anchor end and the ball bearing one of the pillars of the rotor elastic axial element.To ensure the mounting of the rotor on the balancing stand with his high-frequency balancing the body and the cover placed in the outer casing, in which the coaxial cylindrical mounting body and the cover are external cylindrical mounting elements.To ensure reliable lubrication of roller bearings, balancing rotor in the housing, the cover and the outer casing is made channels for supplying and discharging the lubrication of roller bearings.In an external enclosure perpendicular to the axis of the outer cylindrical mounting elements installed sensors deflection of the rotor.In Fig.1 shows a device without external enclosure, and Fig.2 device with an outer housing, where 1 - body; 2 - cover; 3, 4 - internal reference cylindrical surface; 5, 6 - internal reference end; 7, 8 - cylindrical mounting element; 9, 19 - connecting plane; 10 - balancing the rotor; 11, 12 - ball; 13 - elastic axial element;
14 - support ring;
15 - disc springs;
16 - the outer casing;
17 - the lower part of the outer case;
18 - top of the outer casing;
20, 21 to the outer cylindrical mounting element;
22, 23 feeds a supply of lubricant;
24, 25 - channel drain grease;
26, the cover 2, which made the internal reference cylindrical surface 3, 4 and the internal reference end faces 5, 6. On the outer side in the housing 1 and the cover 2 is made of a cylindrical mounting elements 7, 8. The housing 1 and cover 2 are connected on the mating surfaces 9, passing through the axis of the inner cylindrical support surfaces 3, 4. Balancing the rotor 10 with its ball bearings 11, 12 is mounted on the cylindrical support surfaces 3, 4 between the internal reference end faces 5, 6. Between the internal reference end face 6 and the end face of the bearing 12 has an elastic axial element 13 consisting of a support ring 14 and the Belleville springs 15.The housing 1 and the cover 2 is installed in the outer casing 16 (Fig.2) including the bottom 17 and top 18 of its parts, interconnected by connecting planes 19. In an external enclosure 16 coaxial cylindrical mounting body 1 and the cover 2 has an external cylindrical mounting elements 20, 21.In case 1, the cover 2 and the outer casing 16 provided with channels for supplying lubricant 22, 23. In the housing 1 and the lower part 17 of the outer case is made channels draining the lubricant 24, 25. On both sides of each bearing is made gap-type seals 26, 27, 28, 29. Balancedue exnem housing 16 is installed sensors trough 31, 32 of the rotor.Low-frequency balance is produced without external housing 16 (Fig.1). Balancing the rotor is installed in the housing 1 and secured therein by a cover 2. The housing 1 together with the cover 2 and a balancing rotor mounted on a balancing machine for cylindrical mounting elements 7, 8.When high-frequency balancing the outer casing 16 (Fig.2) together with the housing 1, a cover 2 and a balancing rotor mounted on a balancing machine for external cylindrical mounting elements 20, 21.In the process of balancing the force of the Belleville springs 15 is betrayed to the bearing 12 through the support ring 14, resulting in a balancing of the rotor 10 is shifted in the axial direction up to the stop in the inner abutment end face 5 and the two ball bearings 11, 12 have the same axial force equal to the force of the Belleville springs 15 elastic thrust element 13. Under the influence of this force in the bearings 11, 12 is fixed axis, and hence the radial clearance. Due to this, when balancing the possibility of precession of the rotor within the radial clearance existing in a ball in the free state in an assembled for balancing the rotor before installing the of vibration of the rotor.For "hard" rotors low-frequency balancing is the final operation prior to Assembly, for example, are measured. The absence of precession of the rotor provides the minimal residual imbalance at low frequency balancing and reduces the dynamic loads acting on the bearings during operation of the turbomachine.For flexible rotors preliminary low-frequency balancing is a preparatory operation before balancing. Preliminary low-frequency balancing provides lower initial loads on the bearings to a level safe for the health of the rotor and systems balancing stand in the high-frequency balancing of the rotor to the correction of its mass. The application of a composite outer housing 16 consisting of a bottom 17 and a top 18 parts, allows high-frequency balancing without disassembly and reassembly of the rotor after the preliminary low frequency its balancing. The absence of precession of the rotor provides a minimum load on the bearings, and the minimal deflections after high-frequency balancing, which improves the working conditions of the rotor structure of the turbomachine and increases its debt is key to its bearings, and its minimum deflections. The deflections of the rotor during high-frequency balancing is controlled by the deflection sensors 31, 32.To ensure reliable long-term operation of the rotor in the high-frequency balancing the ball is fed to the lubrication channels for supplying lubricant 22, 23. After the ball bearings grease drained through the drain grease 24, 25. Gap-type seals 26, 27, 28, 29 limit the leakage of lubricant from the cavity of ball bearings.The proposed device for the balancing of high-speed rotor of the turbomachine has the following advantages.1. Excluded precession and its associated rotor imbalance, both at low and at high frequency the balance, which improves the working conditions of the rotor structure of the turbomachine and increases its durability.2. After a preliminary low-frequency balancing the rotor without disassembly and re-Assembly is subjected to high-frequency balancing. This provides low initial dynamic loads during high-frequency balancing to correct its mass. This provides high quality and low complexity high-frequency balancing.The practical use of the proposed able="text-align:center; margin-top:2mm;">
Claims1. Device for balancing of high-speed rotor of a turbomachine, comprising a housing with an inner cylindrical support surfaces and ends, a connecting plane which has a support, and a cylindrical mounting elements, characterized in that the support is made in the form of a cover, forming together with the case of General internal reference cylindrical surface and end faces, and a cylindrical mounting elements are made in the housing and the cover in alignment with their internal reference cylindrical surfaces.2. Device for balancing of high-speed rotor of the turbomachine under item 1, characterized in that between the inner abutment end and the ball bearing one of the pillars of the rotor elastic axial element.3. Device for balancing of high-speed rotor of the turbomachine under item 1, characterized in that the housing and the cover are placed in the outer casing, in which a coaxial cylindrical mounting body and the cover are external cylindrical mounting elements.4. Device for balancing the rotor high-speed are measured in points. 1 and 3, characterized in that the housing cover and the outer housing wyprawki rotor high-speed are measured in points. 1 and 3, characterized in that in an external enclosure perpendicular to the axis of the outer cylindrical mounting elements installed sensors deflection of the rotor.
FIELD: mechanical engineering; testing facilities.
SUBSTANCE: invention can be used for stand tests of pumps of any application. According to proposed method full pressure at pump input is maintained constant by means of reservoir with free surface of liquid exposed to constant (atmospheric) pressure installed in intake pipeline. Working liquid saturated vapor pressure at pump input is changed by heating. Periodical measurement of required parameters in process of liquid heating makes it possible to calculate sought for cavitation margin Δh. Method is implemented by test stand containing pump to be tested, output throttle, flow meter, heat exchanger, service tank, pipe fittings, all arranged in closed hydraulic circuit, and reservoir with free surface of working liquid in combination with capsule made of heat conducting material connected to circuit at pump input. Space of capsule is divided into two parts, one of which is partly filled with working liquid and sealed, and other communicates with circuit.
EFFECT: improved accuracy of measurements and simplified determination of pump cavitation characteristics.
3 cl, 1 dwg
FIELD: mechanical engineering.
SUBSTANCE: invention relates to devices aimed at reduction of cavitation in hydraulic machines. Method precludes break of liquid flow at striking of liquid against parts of hydraulic machines by forming controllable flow in near the boundary areas of hydraulic machines and increasing kinetic energy owing to imparting rotating component to flow in direction of movement of pump impeller. Plasticity is imparted to liquid flow by delivering air in amount of 2-5% of amount of supplied water. Device to reduce cavitation includes section of hydraulic machine pipeline made straight and eccentrically narrowing with profiled resistance elements in form of fragments of Archimedean spiral installed on its walls along passage part with inclination in flow. Section is arranged before centrifugal pump. Ratio of larger diameter of pipeline section to its smaller diameter is 1.8-1.5, and ratio of length of section to larger diameter is 1.5-2.0. Section is furnished with cylindrical rarefaction chamber installed before pump and with device to feed air into rarefaction chamber.
EFFECT: provision of reduction of cavitation in hydraulic machines.
3 cl, 1 dwg
FIELD: non-positive-displacement pumps.
SUBSTANCE: compressor comprises inlet guiding vanes, working wheels, and guiding vanes of the compressor stages positioned in the flowing section. The working wheel of at least the first stage of the compressor has a conical bushing whose diameter increases downstream. The inlet guiding vanes and guiding vanes of at lest the first stage of the compressor have conical bushings whose diameter decrease downstream. D/d = 0.9-0.99 and D1/d1 = 1.01-1.1, where D is the diameter of the bushing of the working wheel at its inlet, D1 is the diameter of the bushing of the guiding vanes at its inlet, d is the diameter of the bushing of the working wheel of the compressor at its outlet, and d1 is the diameter of the bushing of the guiding vanes at its outlet. The conical surface of the bushing is inclined to the axis of the compressor at an angle of 1-6°.
EFFECT: enhanced reliability and efficiency.
FIELD: manufacture of aircraft engines; compressors of gas-turbine engines.
SUBSTANCE: proposed blade ring of axial-flow compressor includes outer ring with radial holes; blades secured on this ring and on inner ring form inter-blade passages; holes in outer ring are located before leading edge of blades and behind trailing edge; each hole located before leading edge of blade is communicated by means of separate passage with one of holes located behind trailing edge of blade. Passages form waveguides together with holes; they may be made in form of tubes located above outer ring; length of waveguides exceeds distance between holes forming it.
EFFECT: reduction of amplitude of pressure fluctuation generated by rotor blades, thus reducing vibration stresses in compressor structural members.
3 cl, 2 dwg
FIELD: manufacture of aircraft engines; compressors of gas-turbine engines.
SUBSTANCE: proposed stage of axial-flow compressor includes rotor blades 1 and circular wall of housing 2 with holes 3 and 4 which are communicated with gas-and-air passage 5 and are interconnected by separate pipe lines 6 forming waveguides. Holes 3 are made before leading edges of blades and holes 4 are made behind inlet blades.
EFFECT: reduction of vibration stresses in structural members of axial-flow compressor due to reduced amplitude of pressure fluctuations.
4 cl, 2 dwg
FIELD: mechanical engineering.
SUBSTANCE: invention can be used in cooling system of internal combustion engines and water supply systems. Proposed method includes physical action on liquid by providing or stopping delivery of liquid jets into its inlet branch pipe in direction of common liquid flow in inlet branch pipe at appearance of cavitation in pump by opening-closing valve with electromagnetic drive by signal from variable temperature-sensitive resistor. The latter is installed in inlet branch pipe of pump, temperature is zone of its installation is measured and when temperature rises to cause cavitation in liquid, delivery of liquid into inlet branch pipe is provided to compress steam and air bubbles, thus suppressing cavitation. Control of delivery of liquid is provided by temperature-sensitive resistor.
EFFECT: improved reliability of pump, increased capacity and service life.
FIELD: measurement of positive suction head of pumps handling hydrocarbon mixtures.
SUBSTANCE: proposed method includes placing the flask filled with fluid to be handled in pipe line in front of pump ensuring ratio of vapor and liquid phases in flask equal to or close to ratio of phases in flow section of pump cavitation zone. Ratio of vapor and liquid phases in flask and cavitation zone is set taking into account thermal and physical properties of liquid; pressure difference at pump inlet and flask inlet is measured with the aid of differential pressure gauge. Adequate ratio of vapor and liquid phases in flask and in cavitation zone is set by means of design formulae.
EFFECT: enhanced efficiency due to taking into account physical and thermo-dynamic properties of hydrocarbon material of varying composition.
FIELD: mechanical engineering; axial-flow turbomachines.
SUBSTANCE: proposed axial-flow turbomachine with reduced level of pressure fluctuations exciting vibrations of blades and noise contains group or groups of rims of "fixed rim - rotating rim - fixed rim" type and/or "rotating rim - fixed rim - rotating rim" type of compressor and/or turbine type. Number of blades in extreme rims in each group or in separate groups is equal to or multiple, and their relative circumferential arrangement is determined at designing stage basing on experimental or design data to provide minimum level of fluctuations of aerodynamic force on blades of middle rim in group.
EFFECT: reduced noise level owing to reduction of pressure fluctuations on blades of middle rim in group.
FIELD: mechanical engineering; multistage centrifugal pumps.
SUBSTANCE: proposed pump contains electric motor, impeller unit, end face seals, sliding supports, axial pivot and radial force balancer. Device is made in form of hydrostatic ring. Hydrostatic ring is turnable and is installed from side of first stage of impeller unit in zone of sliding support on pump shaft bushing. Space and bore are made in hydrostatic ring interconnected by channel, bore being hydraulically coupled through adjustable restrictor with pressure duct of pump. Space is made to arc.
EFFECT: reduced vibrations of pump by stabilizing position of rotor of electric motor owing to creating balancing hydrostatic radial force of opposite end of shaft.
2 cl, 2 dwg
FIELD: space engineering, aviation industry, watercraft industry, mechanical industry, etc.
SUBSTANCE: onto input and/or output of axial ventilator, noise damping device is mounted, made in form of head of alternating layers of elastic material with high and low density, connected by holding element in meeting points. Layer of elastic material with high density is compressed between layers of elastic material with low density, while both materials are held inside the cover of air-impenetrable fabric for prevention of blowing out by air flow of layers of elastic materials with high and low density. To impart given shape to head for input and/or output of air, shape-forming frame is contacted.
EFFECT: at frequencies lower than 1000 Hz device operates not worse than prototype, at frequencies above 1000 Hz device allows to decrease noise from axial ventilator mounted on space object by 2-10 decibels and simultaneously to simplify mounting technical under space flight conditions while also decreasing its mass-dimensional characteristics.