The method of repair parts, mainly blades, gas turbine engines
(57) Abstract:The invention relates to aircraft engine industry and can be used in aviation, shipbuilding and automotive industries. The method includes removing the protective coating, defects, surface preparation and application of a new protective coating. Repair parts with a protective coating of zirconium nitride before removing the protective coating to soften complete peeling or swelling, maintaining the blades in the bath with bubbling. This set of blades in the tub in a checkerboard pattern, directing them to one side of the input edge, and positioning them so that the distance between the input and output edges of the adjacent blades not less than half the average chord section of the blade. Remove protective coatings and surface preparation for application of a new protective coating is carried out in the torus sleeve vibration setting processing of ceramic granules. After applying a new protective coating to equalize its irregularities and seal steel balls. The invention will improve the quality of repair and reliability of refurbished products with protective pokrytie. 1 C.p. f-crystals. The invention relates to aircraft engine industry, in particular to the repair of blades for gas turbine engines, and can be used in aviation, shipbuilding and automotive industries.There is a method of repair of blades for gas turbine engines lies in their inspection, the removal of the surface layer in the container vibratory grinding granules, not having open porosity, using as a medium slightly alkaline composition, with the subsequent surface hardening of blades is carried out by processing the stream of powder Nickel alloy with a particle size of 50-100 μm (See. RF patent 2094200, CL. 23 P 6/00, publ. 27.10.97).This method cannot be used to repair parts with a protective coating of zirconium nitride as such a coating cannot be removed vibratory grinding granules, not having open porosity, and, in addition, the blades with a protective coating of zirconium nitride is impractical to process the stream of powder Nickel alloy, as it leads to changes in their geometric parameters (reduction of the chord, the thickness of the input and output edges, as well as to the deterioration of surface cleanliness)oil, consisting in the removal of the protective coating, defects, surface preparation and application of a new protective coating (See. RF patent 2113964, CL. 23 P 6/00, 27.06.98).The disadvantages of this method are that the removal of the protective coating is produced by galvanic methods in solutions that may not be used to remove zirconium nitride, because they are not able to loosen. In addition, with this repair restores a coating (silver, copper and so on), which usually requires surface preparation, sandblasting, which reduces the purity of the surface.Thus, the known methods do not allow to produce high-quality repair of blades having a protective coating of zirconium nitride.The objective of the invention is improving the quality of repair and reliability of refurbished products with a protective coating of zirconium nitride, without the use of manual operations, and improving the surface finish of the repaired GTE blades.The problem is solved by that in the method of repair parts, mainly blades, gas turbine engines, including the removal of the protective coating, the device is m a coating of zirconium nitride before removing the protective coating to soften complete peeling or swelling, maintaining the vanes in the hot bubbling in the solution of the following composition:
chromic anhydride, 5 to 10 g per 1 liter of water
nitric acid - 100-140 g on 1 l of water
hydrofluoric acid - 9-12 g on 1 l of water
when the temperature of the solution 20-30oWith set of blades in the tub in a checkerboard pattern, directing them to one side of the input edge, and positioning them so that the distance between the input and output edges of the adjacent blades not less than half the average chord section of the blade, and removing the protective coating and surface preparation for application of a new protective coating is carried out in the torus sleeve vibration setting processing of ceramic granules, after applying a new protective coating to equalize its irregularities and seal steel ball surface is not lower than grade 9 in the torus sleeve vibrating installed in the polishing solution.A polishing solution may be a solution of 7-12 g triethylamine to 1 liter of water or a solution of naphthenic soap on triethylamine.After softening the protective coating can be lightening the surface of 2-5% aqueous solution of hydrochloric acid, which allows palestinia blades in the bath, because you must install the highest number of blades of at least the size of a bath.Experimentally selected minimum distance between the input and output edges of the adjacent blades, which is not less than half the average chord section of the blade provides a complete loosening of the coating, excluding corrosion of the base material and the possibility of placing the maximum number of blades.The implementation of the method is examined on the example of compressor blades of GTE, made of a material VTZ-1 with subsequent coating of zirconium nitride by sputtering in vacuum at facilities map-1.However, this method can be used for repair and other parts of the CCD, having a coating of zirconium nitride.Gas turbine engines received in repair after running out of warranty or repair resource disassembled for parts or repair which is carried out as follows:
- blades are loaded into the bath with any alkaline solution, which is purification from the production impurities;
- wash the blades in hot water;
- loosen the nitride coating, circulate 100-140 g on 1 l of water, hydrofluoric acid 9-12 g on 1 l of water at a temperature of 20-30 solutionoC. Blades have staggered to one side of the input edge to the distance between the input and output edges of the adjacent blades not less than half of the average chord section of the blade, and include sparging (air supply pressure, eliminating spray solution). After swelling of the coating or peeling blades are removed from the bath and make the operation of lightening in a 2-5% solution of hydrochloric acid;
- make the final destruction of the protective coating and improving the cleanliness of the surfaces of the blades in the torus sleeve vibration setting in the desktop agent type ceramic pellets by known methods;
- blades are removed from the container installation and washed in hot water;
- conduct a special inspection LUM-1-S on the detection of micro-cracks and other defects;
- make the fault detection of the blades in accordance with the "Guide overhaul";
- repair provided "Guidance on major maintenance (polishing, heat treatment, polishing, control and so on) to ensure the geometry and strength characteristics;
- podloterejnyj granules PT-5, dipped in the following solution: trinacria phosphate - 80 g/l, sodium carbonate, 100 g/l, sodium nitride 100 g/l for 40 (+10) minutes;
- the coating of zirconium nitride carried out in a known manner, for example by sputtering in vacuum on the installation map-1;
after coating of zirconium nitride on the blades to produce alignment in the torus sleeve vibratory installation according to the above technology of surface preparation in the same solution, but within 20 minutes;
after leveling of the coating to produce a seal in the torus sleeve vibrating installed in a polishing solution (7-12 g triethylamine to 1 liter of water or naphthenic soap on triethylamine) steel balls of SH-15 with a purity of not lower than grade 9 for 20 (+10) minutes;
- refurbished blades direct on site Assembly of the rotors of the compressor.The result is the elimination of manual operation of the polishing and the increase in the number of valid repair parts due to the limited removal of metal in the repair. The proposed method also allows you to exclude the operation of blowing blades oxide for better adhesion of the coating with the basic material and to increase the purity of coating at least denudata protective coating, elimination of defects, surface preparation and application of a new protective coating, characterized in that in the repair parts with a protective coating of zirconium nitride, before removing the protective coating to soften complete peeling or swelling, maintaining the blades in a tub of bubbling in the solution of the following composition, g on 1 l of water:
Chromic anhydride - 5-10
Nitric acid - 100-140
Hydrofluoric acid - 9-12
when the temperature of the solution 20-30oWith set of blades in the tub in a checkerboard pattern, directing them to one side of the input edge, and positioning them so that the distance between the input and output edges of the adjacent blades not less than half the average chord section of the blade, and removing the protective coating and surface preparation for application of a new protective coating is carried out in the torus sleeve vibration setting processing of ceramic granules, after applying a new protective coating to equalize its irregularities and seal steel ball surface is not lower than grade 9 in the torus sleeve vibrating installed in the polishing solution.2. The method according to p. 1, characterized in that after softening the protective
FIELD: reconditioning of threads of components.
SUBSTANCE: the invention is dealt with repair and recovery of threads on components. Machining is realized by two tools with electrocontact heating of a rotating component. The first tool is installed in a position located in a cavity of a standard thread and conduct finishing-strengthening machining. The second tool is positioned in the beginning of a worn thread and displaced in respect to the first. Movement of the second tool is exercised along the spiral line at the point of overlapping of coils of the threads of the first and second tools and the electrocontact reconditioning is made at the expense of plastic redistribution of the material. The machining is realized with a different force of pressing of the tools to the treated surfaces. The invention allows to restore the profile of the thread and to improve its properties on the components having a wear on a separate section along the length of the of a spiral surface.
EFFECT: the invention ensures reconditioning of the profile of the thread, improvement of its properties on the components having the worn separate sections along the length of the spiral surfaces.
FIELD: manufacture or restoration of worn surfaces of parts, mainly of carbon construction steels.
SUBSTANCE: method comprises steps of plotting (before deformation) curves of plastic yielding of austenite in real coordinates "stress-deformation"; setting according to curves of plastic yielding mode of hot plastic deformation; performing single heating up to temperature higher than Ac3, hot plastic deformation in selected modes and quenching. Isothermic seasoning of parts is performed before quenching for creating polygonal structure of hot-deformed austenite. Quenching is realized directly after hot plastic deformation without isothermic seasoning of hot-deformed austenite. Material is shifted due to metal reserved at stage of making parts.
EFFECT: enhanced constructional strength of parts of carbon construction steel, lowered energy and materials consumption.
4 cl, 2 ex
FIELD: restoration of cast iron rolling rolls with journals damaged at operation.
SUBSTANCE: method comprises steps of mechanically removing damaged layer and performing electric arc surfacing of rotated roll in place of damaged layer removal while feeding steel austenite wire electrode with diameter 3 - 5 mm to welding zone. Surfacing is realized at density of electric current 30 - 40 A/sq. mm and at electrode feeding speed 80 - 110 m/h. After surfacing journal is subjected to spontaneous cooling.
EFFECT: possibility for completely restoring geometry size of operational properties of damaged roll at keeping the same values of its hardness and strength.
1 tbl, 1 ex
FIELD: machine part restoration, namely restoration methods suitable for using in aircraft engines, machine engineering and other branches of technology for restoring rubbing surfaces of cylindrical parts.
SUBSTANCE: method comprises steps of mounting on surface of part prepared for restoration before surfacing, blank of additive material in the form of band; using band with thickness 0.1 - 5.0 mm and mounting it at gap no more than 0.2 mm; performing multi-layer surfacing of additive material in vacuum by means of scanning electron beam; mechanically working part after surfacing each layer of additive material.
EFFECT: simplified process of surfacing material, elimination of residual stresses and deformations in article.
11 cl, 2 dwg, 1 tbl
FIELD: strengthening carrying parts of railway road moving stock, mainly over-spring beams of carriages with center plate.
SUBSTANCE: method comprises step of placing wear -resistant insert to center plate seat enlarged seat by heating it at least until 250°C. Then insert is loaded for closely pressing it to supporting surface at resting of over-spring beam upon its lower band by action of spinning tool having convex surface engaged with insert in order to bend supporting surface of center plate and provide its elastoplastic deforming at residual deformations no more than 0.3%. Elastoplastic deforming is started at time moment of occurring (at cooling process) tightness between beads of center plate and insert and it is terminated at touching of whole contact surfaces of insert and spinning tool at temperature of center plate no more than 150°C. Then over-spring beam is unloaded.
EFFECT: increased useful life period of center plate assembly due to enhanced fatigue resistance of center plate and wear resistance of its supporting surfaces.
1 dwg, 1 ex
FIELD: metal working, namely metal flaw removing by multi-pass electron-beam welding, possibly manufacture of parts of aluminum and its alloys in power production, metallurgical industry branches.
SUBSTANCE: method comprises steps of melting zone of flaw by means of electron beam moving at variable frequency and amplitude during welding cycle along path of eight-beam raster; positioning focus of beam on surface of article or defocusing beam due to changing focusing electric current by value no more than +/- 5% of value of electric current passing at arrangement of focus on surface of article; during period of electric current decrease performing welding procedure in such a way that to lower width of each successive layer in comparison with previous one. Surface area of welded joint central zone formed in result of crossing portion of welded joint in each direction of eight-beam raster is no more than 1/25 of total surface area of welded seam.
EFFECT: enhanced quality of welded joint.
1 cl, 1 dwg
FIELD: railway road moving stock, namely restoration and strengthening of mounting seats for bearings of journal boxes.
SUBSTANCE: method comprises steps of building up end portions of axles of mounting seats of journals subjected to restoration and strengthening by surfacing metal whose mechanical properties are no less than those of axle metal in order to lengthen said end portions by value that is equivalent by volume to worn volume of mounting seats while taking into account allowance for mechanical working; alternatively locally heating mounting seats up to temperature higher than Ac3 in Fe-C diagram and performing their lengthwise hot upsetting at applying load normal relative to end surface of axle arranged near restored mounting seat until widening it along its whole length while taking into account allowance for mechanical working; cooling heated part of axle in air until temperature lower than 600°C; similarly upsetting mounting seat of opposite side of axle; centering end faces and mechanically working mounting seats and end portions of axle.
EFFECT: increased useful life period, enhanced operational reliability of wheel pair axles.
FIELD: processes for restoring steam turbine blades with damaged edges.
SUBSTANCE: method comprises steps of removing worn portion and then surfacing in impulse mode metal whose ductility exceeds that of blade material; welding on protection cover strip by two seams while forming one seam on base material of blade and forming other seam on surfaced metal. Surfaced metal has high cracking resistance; its melting temperature is less than that of base material of blade. Heat treatment with use of heat insulation jacket is performed after surfacing and welding on of protection cover strips.
EFFECT: lowered non-uniformity of structure-phase composition of material of restored blade, reduced tension residual stresses, enhanced resistance of blade against cracking, corrosion and erosion.
4 cl, 1 dwg, 1 tbl
FIELD: restoration of worn parts of aluminum alloys, for example restoration at strengthening of bearing units of gear pumps.
SUBSTANCE: method comprises steps of gas-shield surfacing; mechanical working; strengthening part by micro-arc oxidizing in alkali electrolyte; impregnation of strengthening coating with oil. Micro-arc oxidizing is performed in electrolyte containing 7 g/l of sodium hydroxide and 15 - 16 g/l of potassium-containing liquid glass in anode-cathode mode at using density of cathode current 32 A/dm2 ;relation of cathode and anode currents 1.05 - 1.07; final anode voltage for forming strengthening coating 400 - 420 V; and final cathode voltage 85 - 100 V. Strengthening coating is impregnated with oil (for air crafts) having kinematic viscosity (1.9 - 2.1)10-5 m2/s and heated until temperature 150 - 160°C.
EFFECT: increased oil absorption capacity of strengthening coating due to its increased volumetric porosity, lowered time period of running-in of restored and strengthened parts.
FIELD: processes for repairing laminate articles having different-structure layers, namely noise suppression apparatuses, articles having first and second facings separated by intermediate layer such as honeycomb panels.
SUBSTANCE: method comprises steps of introducing adhesive into zones of exfoliation of facing from honeycomb filler; making fastening member of wire piece and preliminarily imparting to it П-shaped configuration; introducing free ends of П-shaped fastening member in openings for fixing them at tightness; in addition arranging bearing plate on supporting facing and drilling in said plate openings for ends of wire fastening member while aligning openings of plate with openings drilled in panel.
EFFECT: possibility for repairing acoustic honeycomb panel without significant changes of its constructional members at minimum declining of operational characteristics of panel and of the whole engine.
9 cl, 13 dwg