CN102927552A - Shockproof strip assembly for steam generator of nuclear power unit - Google Patents
Shockproof strip assembly for steam generator of nuclear power unit Download PDFInfo
- Publication number
- CN102927552A CN102927552A CN2012103551844A CN201210355184A CN102927552A CN 102927552 A CN102927552 A CN 102927552A CN 2012103551844 A CN2012103551844 A CN 2012103551844A CN 201210355184 A CN201210355184 A CN 201210355184A CN 102927552 A CN102927552 A CN 102927552A
- Authority
- CN
- China
- Prior art keywords
- bar
- end cap
- antivibration
- antivibration bar
- temperature
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Landscapes
- Heat Treatment Of Steel (AREA)
- Forging (AREA)
Abstract
The invention relates to a shockproof strip assembly for a steam generator of a CAP1400 unit. The shockproof strip assembly comprises a shockproof strip of a V-shaped structure and two end caps which are respectively arranged at the two ends of the shockproof strip, wherein the shockproof strip is made from 405 stainless steel material, and the end caps are made from 690 nickel-based alloy material. A method for preparing the shockproof strip assembly comprising the processes of preparation of the shockproof strip, preparation of the end caps, bending and moulding, assembling the end caps, upsetting, inspection, cleaning and packaging. The shockproof strip assembly for the steam generator of the CAP1400 unit provided by the invention is simple in structure, quality of the shockproof strip assembly meets precision requirement of the steam generator in a power nuclear unit on the shockproof strip, and the shockproof strip assembly is safe when being used. The preparation method of the shockproof strip provided by the invention is strict in processes, technological requirements on the shockproof strip assembly for the steam generator in the power nuclear unit are guaranteed, quality is guaranteed, and safety is improved.
Description
Technical field
The present invention relates to a kind of antivibration bar assembly of CAP1400 nuclear power generating sets steam generator.
Background technology
CAP1400 is the code name of the great special demonstration project of presurized water reactor, refers to that China's installed capacity reaches the above advanced non-active nuclear power technology of 1,400,000 multikilowatts.
U-shaped heat transfer tube in the nuclear power station is that most critical also is the weakest link in the circuit system pressure boundary.In case tube vibration destroys, and must change steam generator, this certainly will cause the huge waste of manpower, financial resources and event, has also increased the danger that the maintainer is subjected to radioactivity irradiation.Therefore, so broken the running affairs of solution steam generator is to be related to the security of nuclear power station and to make nuclear power station have the key issue of competitiveness and vitality.
To eliminate the root of generation of vibration as far as possible, generally need in steam generator, install the antivibration bar additional in the elbow of U-shaped heat-transfer pipe, how to provide a kind of resistance to shock good antivibration bar assembly, and the preparation method convenient and simple, that precision is high, be the technical barrier of this area.
Summary of the invention
The technical problem to be solved in the present invention provides the antivibration bar assembly of the good CAP1400 nuclear power generating sets steam generator of a kind of resistance to shock.
The antivibration bar assembly of CAP1400 unit steam generator of the present invention, it comprises: the antivibration bar of V-shape structure and respectively fixed cover be located at two end caps at antivibration bar two ends; The cross section of antivibration bar is rectangular, and the cross section of end cap is three-back-shaped, is beneficial to antivibration bar and end cap and fixes by upsetting pressure.
Described antivibration bar is selected 405 stainless steel materials; Described end cap is selected 690 nickel-bass alloy materials, and the U-shaped heat transfer tube in the unit steam generator also is nickel-bass alloy material, and the two material is identical, can conveniently U-shaped heat transfer tube and described end cap be welded and fixed.690 nickel-bass alloy materials have the strong characteristics of corrosion resistance simultaneously.
Described end cap upsetting pressure is fixed on the described antivibration bar, prevents that end cap from occurring pulling in the assembling of antivibration bar assembly and described U-shaped pipe, welding process.During implementation, the central authorities of described end cap and the part flattening that is close to the end cap two ends at the antivibration bar.
A kind of preparation method of described antivibration bar assembly in turn includes the following steps:
A, antivibration bar bar bent the operation of moulding: with antivibration bar bar on request the size overall length add the 50mm allowance and cut off, set angle bends the antivibration bar, the antivibration bar after bending places on the surface grinding machine, and the bent angle buildup area is carried out reconditioning;
The operation of B, end cap assembling: end cap dabbed with alcohol wash the end cap surface and line cuts endoporus, with alcohol stainless steel bars is cleaned simultaneously, after cleaning up, deburring, bite mark, protrusion metal or wedge angle; Again the end of stainless steel bar is inserted in the endoporus of cap end.
The operation of C, upsetting pressure: (1) pulling-out force procedure qualification: assembling is finished and the end cap that carries out after the upsetting pressure carries out the pulling-out force evaluation, made cap bag under lowest pull, the position is not moved; End pulling-out force under different pressures makes a record, and chooses only pressure, as the pressure process parameter in the upsetting pressure operation; (2) upsetting pressure: the cap end is put into the upsetting pressure mould, respectively upsetting pressure is carried out in the position at the middle position of end cap and the contiguous end cap two ends on the antivibration bar with hydraulic press, depress maintenance pressure off-load after 10 seconds behind the location.Upsetting pressure position on the antivibration bar has everywhere, and each two place, contiguous end cap end are spacing for the cap end is carried out, and prevent that end cap is subjected to displacement at the antivibration bar.
The preparation method of described antivibration bar bar in turn includes the following steps:
A, induction furnace are smelted: place nickel plate, pure iron, crome metal in the induction furnace bottom when alloy material is smelted, and load in mixture closely knit, after the fusing 70%, 2% the slag charge that adds the weight that always feeds intake is made steel, record molten steel temperature and reach after the tapping temperature molten steel is fallen down in the ladle, pour into the steel ingot bar after calm 1-2 minute, effectively improved degree of purity, the structural homogenity of steel alloy, improve surface, the inherent quality of steel ingot, improved the performance of steel alloy.
Antivibration bar alloy material requires pure; Chemical composition accurately, evenly; And the structural state of appointment arranged.Adopt induction furnace to have a series of unarguable advantages.Because it does not have existing pollution sources in other equipment, can guarantee to obtain the purest metal material concerning carbon and other impurity; Thereby stir the uniformity that metal bath guarantees alloy owing to have electric power; Guarantee to obtain exactly and keep the needed temperature of metal and temperature is evenly distributed along whole bath temperature; Eliminate hot-spot; Because its thawing speed is fast, iron loss is few, thereby for obtaining accurately the regulation alloying component, minimum melting loss of elements creates favorable conditions; It has very high mobility when changing the refining chemical composition metal different from forehearth.
B, forging: the alloy material steel ingot after will smelting by induction furnace is forged into the steel billet of 50*50mm size after 1150-1220 ℃ of heating and insulation; By delivering to hot rolling of lower step blank operation after the surface finish reconditioning.
Forging is that a kind of metal forming machinery that utilizes is exerted pressure to metal stock, make it produce plastic deformation to obtain to have the processing method of certain mechanical performance, definite shape and size forging, can eliminate the defectives such as cast condition that metal produces is loose by forging in smelting process, optimize heterogeneous microstructure, owing to preserved complete metal streamline, the mechanical performance of forging generally is better than the foundry goods of same material simultaneously.The strength member that load is high in the associated mechanical, condition of work is severe except the better simply available rolling sheet material of shape, section bar or weldment, adopts forging more.In general forging is that the first step that belongs to materials processing is called " cogging "
C, hot rolling: with antivibration bar alloy material 50 * 50mm blank, carry out hot rolling after placing under the 1050-1100 ℃ of temperature heating, insulation, be rolled into the bar of ф 16mm.
Antivibration bar alloy material becomes the steel of the various geometric cross section shapes that 50 * 50mm blank rolls into blank with the mode of heating by hammer cogging.Different according to the sectional shape shape, be divided into simple section, compound section or three kinds of shaped steel such as special-shaped section and die rolled section.
(1) hot rolling can significantly reduce energy consumption, reduces cost.Plastic deformation is high during hot rolling, and resistance of deformation is low, has greatly reduced the energy consumption of flow of metal.
(2) hot rolling can improve the process industrial art performance of metal and alloy, and the coarse grain that is about to as-cast condition is broken, and significantly crack healing reduces or eliminates casting flaw, with the Deformation structure that as-cast structure changes refinement into, puies forward heavy alloyed processing characteristics.
(3) the hot rolling large ingot casting of antivibration bar alloy material by adopting, heavy reduction rolling has not only improved production efficiency, and is that condition has been created in serialization and the automation that improves mill speed, the realization operation of rolling.
(4) manufacturing procedure was the essential step that forms the finished product blank in the middle of in fact hot-rolled process belonged to.
D, the first heat treatment (annealing heat treatment): process for the surface quality that the guarantees antivibration bar alloy material bar after to hot rolling carries out carrying out vacuum annealing after surface finish, the reconditioning again, φ 16 antivibration bar alloy material bars heat, are incubated under 800 ℃ ± 10 ℃ of temperature.
Annealing heat treatment is divided into full annealing, partial annealing and stress relief annealing.The mechanical property of annealed material can detect with tension test, also can detect with hardness test.Intermediate heat-treatment is named again in advance heat treatment, is for the defective of eliminating a upper procedure or makes the back operation process well the heat treatment that arranges.Be that metal slowly is heated to uniform temperature, keep enough time, a kind of metal heating processing technology that then cools off with Reasonable Speed.
The purpose of annealing
1. improve or eliminate various tissue defects and the residual stress that iron and steel causes in casting, forging and pressing, rolling and welding process, prevent workpiece deformation, cracking.
2. softening workpiece is in order to carry out machining.
3. crystal grain thinning improves tissue to improve the mechanical performance of workpiece.
4. for performing tissue, final heat treatment (quenching, tempering) prepares.
E, cold-drawn: carry out first soft annealing and process, insulation is 40 minutes under 720-750 ℃ of temperature; With glomerocryst mould successively drawing, and effects on surface micro-crack place carries out reconditioning by deformation requirements, and reconditioning can be carried out the drawing of lower road to zero defect.
Cold-drawn is that the antivibration bar alloy bar behind the hot rolling is reprocessed at cold state after soft annealing, to obtain the production method of all kinds of precisions, high-precision product or intermediate products.
F, the second heat treatment: antivibration bar alloy bar is pulled to finished-product material is tiled in the bell-jar heat-treatment furnace, heat-treat under the hydrogen shield state, temperature is 788-815 ℃ between the annealing soak, and insulation is more than 3 hours; Then to be no more than below 28 ℃ of/hour cooling velocity slow cooling to 610 ℃, air cooling is to room temperature again.
Metal heat treatmet is one of important process in the machine-building, compare with other processing technologys, heat treatment does not generally change shape and the whole chemical composition of workpiece, but by changing the microscopic structure of inside workpiece, or change the chemical composition of surface of the work, give or improve the serviceability of workpiece.Be characterized in improving the inherent quality of workpiece, and this generally not to be naked eyes can see.
For making metal works have needed mechanical property, physical property and chemical property, except reasonable selection material and various forming technology, Technology for Heating Processing is requisite often.Iron and steel is material most widely used in the mechanical industry, and microstructure of iron and steel is complicated, can be controlled by heat treatment, so the heat treatment of iron and steel is the main contents of metal heat treatmet.In addition, aluminium, copper, magnesium, titanium etc. and alloy thereof also can change its mechanics, physics and chemistry performance by heat treatment, to obtain different serviceabilities.
G, finished product processing: the bar after processing is aligned, polished.
The rectification that the shape defect of Metal Forming product is carried out; it is one of important finishing procedure; cold-drawn material often can produce the various shapes defective in production process or cooling afterwards and transportation; such as the bending of section bar tubing, wave, wooden dipper song etc.; by various equipment for straightening the defective such as crooked is eliminated under external force, be made product reach qualified perfect condition.
(1) corase grind: the polishing of product except to make smooth surface smooth, the more important thing is and should reduce as far as possible top layer damage.Per one branner's order must be removed the deformation layer (deformation layer that last procedure is produced reduces to the deformation layer degree of depth that this procedure produces) that last procedure causes, rather than only the polishing scratch of last procedure removed; Simultaneously, this procedure itself should accomplish to reduce as far as possible damage, so that carry out next process.The deformation layer degree of depth that last one branner's order produces should be very shallow, guarantees to remove in lower one polishing process.This process will notice preventing that metal from too generating heat.
(2) correct grinding: the purpose of correct grinding is the darker polishing scratch that stays when eliminating corase grind, for next step polishing is laid a solid foundation.Correct grinding normally carries out at sand paper, and sand paper divides waterproof abrasive paper and abrasive paper for metallograph.Usually waterproof abrasive paper is that the SiC abrasive material is water insoluble, the abrasive material of abrasive paper for metallograph has Alundum, carborundum, iron oxide etc., property is all extremely hard, be polygon corner angle, have good cutting ability, available water is carried out manual wet-milling or mechanical wet-milling as lubricant during correct grinding, uses usually that granularity is 240,320,400,600 4 kind of waterproof abrasive paper can polish after polishing, for than the soft metal, use and polish again after thinner abrasive paper for metallograph polishes.Sand paper is downward-sloping (from operator's direction) outwardly, stick on when grinding on the plate glass, on sand paper, straight line pushed away forward and leaves sand paper when returning after the sample flour milling is flat, thisly repeatedly carried out, until old polishing scratch all disappears, obtain the consistent uniformly new polishing scratch limit of direction at whole flour milling and end, whenever change before one sand paper, must first water flush away sample and sand grains on hand, and dry, then the sample half-twist is ground at secondary sand paper.The water that flows during use ceaselessly flows through from coated abrasive surface, in time most abrasive dusts and the abrasive particle that comes off is washed away.Like this in whole polishing operation process, the sharp corners of abrasive particle all the time with the Surface Contact of sample, keep its good ablation.Another advantage of wet grinding is that the frictional heat that produces at specimen surface when the cooling effect of water can reduce polishing avoids microscopic structure to change.Whole polishing operation can be finished with equipment.
The preparation method of described end cap in turn includes the following steps: induction furnace smelting, forging, hot rolling, heat treatment, end cap Vehicle Processing; (needing to replenish effect, purpose or the technique effect of each operation)
Described induction furnace is smelted: place nickel plate, pure iron, crome metal in the induction furnace bottom when alloy material is smelted, and load in mixture closely knit, after the fusing 70%, 2% the slag charge that adds the weight that always feeds intake is made steel, record molten steel temperature and reach after the tapping temperature molten steel is fallen down in the ladle, pour into steel ingot after calm 1-2 minute.
Antivibration bar alloy material requires pure; Chemical composition accurately, evenly; And the structural state of appointment arranged.Adopt induction furnace to have a series of unarguable advantages.Because it does not have existing pollution sources in other equipment, can guarantee to obtain the purest metal material concerning carbon and other impurity; Thereby stir the uniformity that metal bath guarantees alloy owing to have electric power; Guarantee to obtain exactly and keep the needed temperature of metal and temperature is evenly distributed along whole bath temperature; Eliminate hot-spot; Because its thawing speed is fast, iron loss is few, thereby for obtaining accurately the regulation alloying component, minimum melting loss of elements creates favorable conditions; It has very high mobility when changing the refining chemical composition metal different from forehearth.
Described forging: the steel ingot of the antivibration bar alloy material after will smelting by induction furnace is forged into the steel billet of 50*50mm size after 1150-1220 ℃ of heating and insulation; By delivering to hot rolling of lower step blank operation after the surface finish reconditioning.
Forging is that a kind of metal forming machinery that utilizes is exerted pressure to metal stock, make it produce plastic deformation to obtain to have the processing method of certain mechanical performance, definite shape and size forging, can eliminate the defectives such as cast condition that metal produces is loose by forging in smelting process, optimize heterogeneous microstructure, owing to preserved complete metal streamline, the mechanical performance of forging generally is better than the foundry goods of same material simultaneously.The strength member that load is high in the associated mechanical, condition of work is severe except the better simply available rolling sheet material of shape, section bar or weldment, adopts forging more.In general forging is that the first step that belongs to materials processing is called " cogging "
Described hot rolling: with antivibration bar alloy material 50 * 50mm blank, carry out hot rolling after placing under 1200 ± 10 ℃ of temperature heating, insulation, be rolled into the bar of ф 13 * 25mm.
Antivibration bar alloy material becomes the steel of the various geometric cross section shapes that 50 * 50mm blank rolls into blank with the mode of heating by hammer cogging.Different according to the sectional shape shape, be divided into simple section, compound section or three kinds of shaped steel such as special-shaped section and die rolled section.
(1) hot rolling can significantly reduce energy consumption, reduces cost.Plastic deformation is high during hot rolling, and resistance of deformation is low, has greatly reduced the energy consumption of flow of metal.
(2) hot rolling can improve the process industrial art performance of metal and alloy, and the coarse grain that is about to as-cast condition is broken, and significantly crack healing reduces or eliminates casting flaw, with the Deformation structure that as-cast structure changes refinement into, puies forward heavy alloyed processing characteristics.
(3) the hot rolling large ingot casting of antivibration bar alloy material by adopting, heavy reduction rolling has not only improved production efficiency, and is that condition has been created in serialization and the automation that improves mill speed, the realization operation of rolling.
(4) manufacturing procedure was the essential step that forms the finished product blank in the middle of in fact hot-rolled process belonged to.
Described heat treated priority comprises: (1) solution treatment: the end cap material 13*25mm material after the hot rolling is tiled in solution treatment in the bell-jar hydrogen protection stove; (2) Ageing Treatment: also place the hydrogen shield stove to carry out Ageing Treatment the bar after the solution treatment.
Solution treatment is to equate to obtain uniform supersaturated solid solution in order to dissolve carbide in the matrix, γ ', again the hardening constituent such as tiny, the carbide that is evenly distributed of precipitate particle and γ ' when being convenient to timeliness, eliminate simultaneously because the stress that cold and hot working produces makes alloy generation recrystallization.Secondly, solution treatment is for the grain size that obtains to suit, to guarantee the alloy high-temp creep-resistant property.The temperature range of solution treatment between 980 ~ 1250 ℃, is mainly selected according to separating out mutually in each alloy with dissolution law and instructions for use greatly, with the condition of separating out that guarantees main hardening constituent necessity and certain grain size.For the alloy that long term high temperature uses, requiring has preferably high-temperature and durable and croop property, should select higher solid solubility temperature to obtain larger grain size; Use and require the preferably alloy of room temperature hardness, yield strength, hot strength, impact flexibility and fatigue strength for middle temperature, can adopt lower solid solubility temperature, guarantee less grain size.When high temperature solid solution was processed, various precipitated phases are progressively dissolving all, simultaneously grain growth; During the low temperature solution treatment, the dissolving of main hardening constituent is arranged not only, and separating out of some phase may be arranged.For the low alloy of degree of supersaturation, usually select faster cooling velocity; For the high alloy of degree of supersaturation, be generally in the air and cool off.
Ageing Treatment: refer to alloy workpiece through solution treatment, cold plastic deformation or casting after the forging, keep its performance, shape, the Technology for Heating Processing of size time to time change in higher temperature placement or room temperature.If adopt workpiece is heated to higher temperature, and the short period carry out the aging treatment process of Ageing Treatment, be called artificial aging and process, the aging phenomenon that occurs if workpiece is placed on long storage time under room temperature or the natural conditions is called natural aging treatment.The third mode be oscillating aging from the eighties from the beginning of progressively entering the practical stage, oscillating aging is processed then and not to be heated also in the situation time-consuming unlike natrual ageing, with the vibration that applies certain frequency to work its internal stress is released, thereby reaches the purpose of timeliness.The purpose of Ageing Treatment, the internal stress of elimination workpiece, stabilizing tissue and size are improved mechanical performance etc.
In machinery production, in order to stablize casting dimension, often foundry goods is at room temperature placed for a long time, just then carry out machining.This measure is also referred to as timeliness.But this timeliness does not belong to metal heating processing technology.
Described end cap Vehicle Processing: the 13*25mm material after the Ageing Treatment is machined, be processed into the end cap of required size.
Technique effect of the present invention: the antivibration bar assembly of CAP1400 unit steam generator of the present invention, simple in structure, product quality meets in the nuclear power station steam generator to the accurate requirement of antivibration bar, and is safer during use.The preparation method of this antivibration bar through strict preparation section, has guaranteed in the nuclear power station technological requirement of the antivibration bar assembly of steam generator has been guaranteed quality, has improved security.Described end cap upsetting pressure is fixed on the described antivibration bar, prevents that end cap from occurring pulling in the assembling of antivibration bar assembly and described U-shaped pipe, welding process.During implementation, the central authorities of described end cap and the part flattening that is close to the end cap two ends at the antivibration bar.
Description of drawings
Fig. 1 is the structural representation of the antivibration bar assembly of CAP1400 unit steam generator of the present invention, Reference numeral: 1--antivibration bar, 2--end cap;
Fig. 2 is the top view of Fig. 1;
Fig. 3 is the profile at the end cap place in the antivibration bar assembly of Fig. 1.
The specific embodiment
Such as Fig. 1, the antivibration bar assembly of the CAP1400 unit steam generator of present embodiment, it comprises: the antivibration bar 1 of V-shape structure and respectively fixed cover be located at two end caps 2 at antivibration bar two ends; The cross section of antivibration bar is rectangular, and the cross section of end cap is three-back-shaped, is beneficial to antivibration bar and end cap and fixes by upsetting pressure.
Described antivibration bar 1 is selected 405 stainless steel materials (SA-479 TYPE405); Described end cap 2 is selected 690 nickel-bass alloy materials (SB-166 UNS N06690).
Being crushed everywhere of contiguous end cap two ends on the central authorities of described end cap 2 and the antivibration bar 1.Two flattenings place that are in the end cap end at antivibration bar 1 are symmetrical.
The preparation method of above-mentioned antivibration bar assembly comprises: the preparation of antivibration bar bar, the preparation of end cap, antivibration bar bar bend the operations such as moulding, end cap assembling, upsetting pressure, inspection, cleaning and packing.
Described antivibration bar bar bends moulding: with antivibration bar bar on request the size overall length add the 50mm allowance and cut off, set angle bends the antivibration bar, the antivibration bar after bending places on the surface grinding machine, and the bent angle buildup area is carried out reconditioning to drawing requirement.
Described end cap assembling: end cap is dabbed the endoporus of washing end cap surface and line excision forming with alcohol, with alcohol stainless steel bars is cleaned simultaneously, after cleaning up, deburring, bite mark, protrusion metal or wedge angle; Stainless steel bar is inserted the cap end, alignment angle is assembled again.
Described upsetting pressure comprises: (1) pulling-out force procedure qualification: assembling is finished and the end cap that carries out after the upsetting pressure carries out the pulling-out force evaluation, made cap bag under the pulling force of minimum 4448N, the position is not moved; End pulling-out force under different pressures makes a record, and chooses only pressure, as the pressure process parameter in the upsetting pressure operation; (2) upsetting pressure: the cap end is put into the upsetting pressure mould, respectively upsetting pressure is carried out in the position at the middle position of end cap and the contiguous end cap two ends on the antivibration bar with hydraulic press, depress maintenance pressure off-load after 10 seconds behind the location, guarantee to satisfy drawing requirement after the upsetting pressure of cap end.Upsetting pressure position on the antivibration bar has everywhere, and each two place, contiguous end cap end are spacing for the cap end is carried out, and prevent that end cap is subjected to displacement at the antivibration bar.
Described inspection: (1) flatness detects, and measures with clearance gauge on detection platform; (2) size detection is used the digimatic micrometer measurement products; (3) angle detects, and measures with digital display angle measuring instrument; (4) visual detection is carried out visual detection to workpiece by part, guarantees surperficial zero defect, and surface roughness is with the roughness measuring instrument measurement of creeping; (5) surface finish measurement is measured with roughness instrument or contrast sample piece; All size detection results should meet drawing requirement.
Described cleaning: bar is cleaned by relevant regulations, guarantee that finished surface does not have rust staining, dust and other pollutants, (1) sulphur, lead, mercury, cadmium and other low-melting metals, and their alloy and compound, halogen-containing material is all forbidden for processes such as the preparation of antivibration bar, test, check and packings; (2) lubricant, cuttings liquid and cleaning agent do not contain above-mentioned substance yet; Molykote, politef and other poly-fluorine materials also ban use of.
The preparation method of the antivibration bar bar in above-described embodiment 1 comprises following operation successively: induction furnace smelting, heat analysis, forging, hot rolling, the first heat treatment, performance test (stretching, hardness) and metal lographic examination, product analysis, cold-drawn, the second heat treatment, finished product processing, performance test (stretching, hardness) and grain size check, dimension control, mark, cleaning.
Described induction furnace is smelted: place nickel plate, pure iron, crome metal in the induction furnace bottom when alloy material is smelted, and load in mixture closely knit, after the fusing 70%, 2% the slag charge that adds the weight that always feeds intake is made steel, record molten steel temperature and reach after the tapping temperature molten steel is fallen down in the ladle, pour into the steel ingot bar after calm 1-2 minute.Every 40-50kg of steel ingot weight, steel ingot diameter microcephaly 140mm, major part 155mm.
Described heat analysis comprises: (1) sampling: car or dig sample for chemical analysis beyond the head of ingot, ingot tail 20mm scope; (2) each heat (batch) number is got the chemical analysis that a sample for chemical analysis is measured every stove steel, and screen by the content standard data.The melting chemical analysis should meet following table and require:
Described forging: will analyze steel ingot after qualified is forged into the 50*50mm size under 1150-1220 ℃ steel billet;
(1) Forge Heating thermometer:
(2) forge: forging compression ratio is: 4-6; Forge size: 50*50mm; More than the square billet major part excision 100mm, the microcephaly excises more than the 50mm; The forging stock surface treatment: the reconditioning that strips off the skin of forging stock surface, remove the blemish such as surperficial wrinkle crackle pipe.
Described hot rolling: steel billet placed under the 1050-1100 ℃ of temperature carry out hot rolling, be rolled into the bar of ф 16mm, will be by the crackle of root check surface quality after the hot rolling cooling, fold, scab, be mingled with, and thoroughly polishing is clean;
(1) the billet heating temperature table is as follows:
(2) rolling: as to adjust the worker outward appearance of rolled products is wanted straight, be rolled into the silk material of ф 16mm; Will pursue root after the milling material cooling and check the crackle of surface quality, fold, scab, be mingled with, and thoroughly polishing is clean; Rolling ratio: 〉=5.
Described the first heat treatment: the bar after the hot rolling is carried out vacuum annealing process, temperature remains on 800 ± 10 ℃;
Described performance test comprises: (1) is appointed each stove lot number of the hot rolled rod after the heat treatment and is got one group of sample; (2) sample is carried out respectively tension test, hardness test, Metallographic Analysis and product analysis, substandard product is got rid of;
1. stretch test result should meet the following table requirement:
| Performance | Room temperature | 350℃ |
| Prescribed strength Rp0.2 (Mpa) | ≥170 | ≥145 |
| Tensile strength Rm (Mpa) | ≥415 | ≥370 |
| Elongation after fracture A(%) | ≥20 | info |
| Contraction percentage of area Z(%) | ≥45 | info |
When bar≤25mm, the longitudinal axis of sample is consistent with the center of bar, and the useful part of sample must not be less than the diameter of bar apart from the distance of bar heat treated end.
2. hardness test should meet:
| Performance | Room temperature |
| Hardness (HB) | ≤207 |
Hardness test should be in the hardness of the middle part of bar center to face check bar.
3. Metallographic Analysis should meet:
4. product analysis: do the material product analysis in the sampling of the two ends of tensile sample, analysis result should meet:
5. retrial and another warm are processed:
5.1 if the stretch test result of bar is undesirable, can cut at the contiguous position of failed test sample two additional samples and carry out tension test, only when all meeting the demands, two additional specimen test results can check and accept;
If cause mechanical property defective 5.2 any a collection of bar heat treatment is improper, then can process this batch of material another warm, but heat treated number of times should be above twice again; After another warm is processed, this batch of material is carried out all checks (except the check of chemical analysis and non-metallic inclusion) of technical conditions regulation; All checks all should meet the requirement of present technique condition.
Described cold-drawn comprises: (1) carries out first the soft annealing processing, and insulation is 40 minutes under 720-750 ℃ of temperature; (2) by deformation requirements with glomerocryst mould successively drawing, and effects on surface micro-crack place carries out reconditioning, reconditioning can be carried out the drawing of lower road to zero defect.
Drawing deflection during cold-drawn is φ 16 → φ 14 → φ 12.5 → φ 11 → 4.8 * 12.8 → 4.4 * 12.5 → 4.028 * 12.19.
The soft annealing resolving system is as follows:
Described the second heat treatment: will be pulled to finished-product material and be tiled in the bell-jar heat-treatment furnace, and heat-treat under the hydrogen shield state, the annealing holding temperature is 788-815 ℃, and heat treatment temperature and other require the according to the form below requirement to carry out:
The processing of described finished product: to the bar after the heat treatment align, the cold working operation such as polishing, the thickness after the processing, width, torsion resistance, linearity equidimension should meet following table and require:
Described performance test: bar is carried out mechanical property test, hardness test, grain size check, and the bar that requires is got rid of to not meeting the specification.
1. mechanical property test should meet:
| Performance | Room temperature |
| Prescribed strength Rp0.2 (Mpa) | 240-550 |
| Tensile strength Rm (Mpa) | 415-585 |
| Elongation after fracture A(%) | ≥15 |
2. hardness test should meet:
| Performance | Room temperature |
| Hardness | HB≤207 or HRB≤93 |
3. grain size check:
| The method of inspection | The rank requirement |
| ASTM?E112 | 5 grades or thinner |
If the mechanical property of bar does not meet specification requirement, then can carry out retrial in the contiguous double sampling in position of this sample, the retrial result requirement that all should meet the specification.
Described dimension control comprises: (1) visual examination: the Zhi Jinhang visual inspection is pursued on every material surface, require the defectives such as flawless, scuffing, bar does not allow to carry out any repair by welding, and its surface roughness checked by Zhi Jinhang, need increase inspection to suspicious district, record the result and answer Ra≤1.6 μ m; (2) dimensional gaughing: take out 5% material and carry out dimensional gaughing, guarantee that scantling satisfies the tolerance of 4.028 ± 0.013* (12.19).
Described mark: on every material, should accurately make the sign or tie on a label, write maker's name exactly, material trademark and specification; Hearth number, lot number and piece number; Contract number or order number.
Described cleaning: by relevant regulations bar is cleaned, guarantee that the finished product Surface of Rod Bar does not have rust staining, dust and other pollutants; Rod iron can not contact the material that itself and integrality is had harm.The incompatibility material of main metal has lead, zinc, copper, aluminium, cadmium, tin, mercury, sulphur, arsenic, boron and general low-melting alloy and their compound thereof, in addition, the fluoride, sulfate, chloride and the acid chloride that produce owing to the degraded of plastic containing chlorine are a potential danger, answer careful selection adhesive tape, marking pen, couplant, bleeding agent and coating; If the use milling tools, it is contaminated to guarantee that at first milling tools does not have.
Embodiment 3
The preparation method of the end cap in above-described embodiment 1 comprises following operation successively: induction furnace smelting, electroslag refining, heat analysis, forging, ultrasonic examination, hot rolling, heat treatment, performance test, product analysis, end cap Vehicle Processing, dimension control, mark, cleaning.
Described induction furnace is smelted: place nickel plate, pure iron, crome metal in the induction furnace bottom when alloy material is smelted, and load in mixture closely knit, after the fusing 70%, adding 2% the slag charge always feed intake makes steel, record molten steel temperature and reach after the tapping temperature molten steel is fallen down in the ladle, pour into the steel ingot bar after calm 1-2 minute, every 40-50kg of steel ingot weight, steel ingot diameter microcephaly 140mm, major part 155mm.
Described electroslag refining: alloy material will could improve through electroslag refining degree of purity, the structural homogenity of steel alloy effectively through after smelting, and improves surface, the inherent quality of steel ingot, improves the performance of steel alloy.When electroslag refining is complete, carry out feeding, after feeding 3-5 minute, cool off and took off ingot in 〉=3 minutes.Then carry out the ESR ingot surface treatment: the surface strips off the skin, reconditioning.
Described heat analysis comprises: (1) sampling: car or dig sample for chemical analysis beyond the head of ingot, ingot tail 20mm scope; (2) each heat (batch) number is got a sample for chemical analysis, test method by " ASTM E38 nickel-chromium and nickel-chromium-ferro alloy chemical analysis method " requirement is carried out the chemical analysis analysis to material, and screen by the content standard data, the melting chemistry should meet:
Described forging: will analyze steel ingot after qualified is forged into the 50*50mm size under 1240-1260 ℃ of temperature steel billet.
1. will carry out annealing in process to steel ingot before forging, the heat treatment temperature according to the form below carries out:
2. deformation technique: forging compression ratio is: 4-6; More than the square billet major part excision 100mm, the microcephaly excises more than the 50mm; Forge square billet and be of a size of 50*50mm; The forging stock surface treatment: the reconditioning that strips off the skin of forging stock surface, remove the blemish such as surperficial wrinkle crackle pipe.
Described ultrasonic examination: the square rod of the reconditioning that will strip off the skin carries out ultrasound examination by detection method and the acceptance criteria of regulation in " bar Dynamic Non-Destruction Measurement condition ".
Described hot rolling: square billet placed under 1200 ℃ of left and right sides temperature carry out hot rolling, be rolled into the material of 13*25mm, the hot-rolled temperature deviation is no more than 10 degree, will be by the crackle of root check surface quality after the hot rolling cooling, the defective such as fold, scab, be mingled with, and thoroughly polishing is clean;
1. the square billet after forging carries out first annealing in process before hot rolling, annealing temperature such as following table:
2. roll control: end cap is rolled into 13*25mm with material; Will be by root check face crack after the milling material cooling, the defective such as fold, scab, be mingled with, and excision or thoroughly polishing is clean; Rolling ratio is 〉=5.
Described heat treatment comprises: 1. solution treatment: the end cap material 13*25mm material after the hot rolling is tiled in solution treatment in the bell-jar hydrogen protection stove, heat treatment temperature such as following table:
| Phosphorus content wt.% | Minimum holding temperature ℃ |
| 0.015 | 1016 |
| 0.016 | 1023 |
| 0.017 | 1030 |
| 0.018 | 1036 |
| 0.019 | 1043 |
| 0.020 | 1049 |
| 0.021 | 1055 |
| 0.022 | 1060 |
| 0.023 | 1066 |
| 0.024 | 1071 |
| 0.025 | 1076 |
| 0.026 | 1081 |
| 0.027 | 1085 |
| 0.028 | 1090 |
| 0.029 | 1094 |
| 0.030 | 1099 |
Wherein, the holding temperature deviation be no more than ± 10 ℃.
2. Ageing Treatment: the bar after the solution treatment must carry out Ageing Treatment, and Ageing Treatment also should be carried out in the hydrogen shield stove, and heat treatment temperature is:
Wherein, Ageing Treatment should be above ± 10 ℃ at the temperature deviation of soak.
3. solid solution and timeliness heat treatment record should be listed in the certificate of quality file, and the heat treatment record should comprise holding temperature and deviation, temperature retention time, the rate of heat addition, heating atmosphere and the type of cooling.
Described performance test comprises:
1. sampling: each stove lot number is appointed and is got a sample and do mechanical property test, the longitudinal axis of tensile sample be parallel to bar axially.The useful part of tensile sample is at least one times of diameter of rod from the bar end; The residing position of the longitudinal axis of tensile sample is the bar center; Sample has enough length, so that all test consumptions and the required samples of possibility retrial such as intercepting hardness sample, metallographic specimens.
2. tension test should meet:
Wherein, the standard specimen of gauge length 50mm, diameter 12.5mm is adopted in tension test.
3. Metallographic Analysis: Metallographic Analysis is done in the sample close position sampling in tension test, and the Metallographic Analysis examination criteria is:
4. macro-erosion test: appoint one of extraction to carry out the macroetch test for every batch, should test at crop cross section position, the two ends of bar, with the naked eye or by magnifying glass below 10 times evaluate, do not allowed the defectives such as shrinkage cavity, cavity, crackle, slag inclusion and pin hole.
5. Huey test: the every batch of bar should any bar after Ageing Treatment be got one group of (two) sample and is carried out Huey test, sample is got in the stretching adjacent locations, sample should be processed through sensitization first, the sensitization resolving system be 675 ℃ ± 5 ℃ the insulation 1 hour, the sample corrosion rate should less than 20mdd (milligram/square decimeter. day).
6. product analysis: each stove is appointed and is got the product analysis that a sample is done material near tensile sample, and the product analysis result should meet:
Described end cap Vehicle Processing: the 13*25mm material after the Ageing Treatment is made a service test, and qualified material is machined, be processed on request φ 22.86 ± 0.05, long 50.8 ± 0.07 end cap product.
Described dimensional gaughing: 1, the Zhi Jinhang visual inspection is pursued on every material surface, end cap has not allowed indentation, burr, lobe, metal to heave.2, material is carried out dimensional gaughing, the inspection quantity of every stove material should be greater than 5%.
Described mark: on every material, should accurately make the sign or tie on a label, should comprise: job number, material trademark and specification, bar piece number, hearth number, heat treatment heat (batch) number, bar maker's name.
Described cleaning: by relevant regulations bar is cleaned, guarantee that finished product end cap surface does not have rust staining, dust and other pollutants.
Claims (6)
1. the antivibration bar assembly of a CAP1400 nuclear power generating sets steam generator is characterized in that comprising: the antivibration bar of V-shape structure and respectively fixed cover be located at the end cap at antivibration bar two ends; The cross section of antivibration bar is rectangular, and the cross section of end cap is three-back-shaped.
2. the antivibration bar assembly of CAP1400 nuclear power generating sets steam generator as claimed in claim 1, it is characterized in that: described antivibration bar is selected 405 stainless steel materials; Described end cap is selected 690 nickel-bass alloy materials.
3. the antivibration bar assembly of CAP1400 nuclear power generating sets steam generator as claimed in claim 1 or 2, it is characterized in that: described end cap upsetting pressure is fixed on the described antivibration bar.
4. the preparation method of the claims 2 described antivibration bar assemblies is characterized in that in turn including the following steps:
A, antivibration bar bar bent the operation of moulding: with antivibration bar bar on request the size overall length add the 50mm allowance and cut off, set angle bends the antivibration bar, the antivibration bar after bending places on the surface grinding machine, and the bent angle buildup area is carried out reconditioning;
The operation of B, end cap assembling: end cap dabbed with alcohol wash the end cap surface and line cuts endoporus, with alcohol stainless steel bars is cleaned simultaneously, after cleaning up, deburring, bite mark, protrusion metal or wedge angle; Again the end of stainless steel bar is inserted in the endoporus of cap end;
The operation of C, upsetting pressure: the cap end is put into the upsetting pressure mould, respectively four points at the middle position of end cap and the contiguous end cap two ends on the antivibration bar are carried out upsetting pressure with hydraulic press, depress maintenance pressure off-load after 10 seconds behind the location.
5. the preparation method of antivibration bar assembly according to claim 4, it is characterized in that: the preparation method of described antivibration bar bar in turn includes the following steps:
A, induction furnace are smelted: place nickel plate, pure iron, crome metal in the induction furnace bottom when alloy material is smelted, and load in mixture closely knit, after the fusing 70%, 2% the slag charge that adds the weight that always feeds intake is made steel, record molten steel temperature and reach after the tapping temperature molten steel is fallen down in the ladle, pour into the steel ingot bar after calm 1-2 minute;
B, forging: the alloy material steel ingot after will smelting by induction furnace is forged into the steel billet of 50*50mm size after 1150-1220 ℃ of heating and insulation, and carries out the surface finish reconditioning;
C, hot rolling: with antivibration bar alloy material 50 * 50mm blank, carry out hot rolling after placing under the 1050-1100 ℃ of temperature heating, insulation, be rolled into the bar of ф 16mm;
D, the first heat treatment: process for the surface quality that the guarantees antivibration bar alloy material bar after to hot rolling carries out carrying out vacuum annealing after surface finish, the reconditioning again, φ 16 antivibration bar alloy material bars heat, are incubated under 800 ℃ ± 10 ℃ of temperature;
E, cold-drawn: carry out first soft annealing and process, insulation is 40 minutes under 720-750 ℃ of temperature; With glomerocryst mould successively drawing, and effects on surface micro-crack place carries out reconditioning by deformation requirements, and reconditioning can be carried out the drawing of lower road to zero defect;
F, the second heat treatment: antivibration bar alloy bar is pulled to finished-product material is tiled in the bell-jar heat-treatment furnace, heat-treat under the hydrogen shield state, temperature is 788-815 ℃ between the annealing soak, and insulation is more than 3 hours; Then to be no more than below 28 ℃ of/hour cooling velocity slow cooling to 610 ℃, air cooling is to room temperature again;
G, finished product processing: the bar after processing is aligned, polished.
6. the manufacture method of antivibration bar assembly according to claim 4, it is characterized in that: the preparation method of described end cap comprises following operation successively: induction furnace smelting, forging, hot rolling, heat treatment, end cap Vehicle Processing;
Described induction furnace is smelted: put nickel plate, pure iron, crome metal in the induction furnace bottom when alloy material is smelted, and load in mixture closely knit, after the fusing 70%, 2% the slag charge that adds the weight that always feeds intake is made steel, record molten steel temperature and reach after the tapping temperature molten steel is fallen down in the ladle, pour into steel ingot after calm 1-2 minute;
Described forging: the alloy material steel ingot after will smelting by induction furnace is forged into the steel billet of 50*50mm size after 1150-1220 ℃ of heating and insulation, and carries out the surface finish reconditioning;
Described hot rolling: with antivibration bar alloy material 50 * 50mm blank, carry out hot rolling after placing under 1200 ± 10 ℃ of temperature heating, insulation, be rolled into the bar of ф 13 * 25mm;
Described heat treatment successively comprises: (1) solution treatment: the end cap material 13*25mm material after the hot rolling is tiled in solution treatment in the bell-jar hydrogen protection stove; (2) Ageing Treatment: also place the hydrogen shield stove to carry out Ageing Treatment the bar after the solution treatment;
Described end cap Vehicle Processing: the 13*25mm material after the Ageing Treatment is machined, be processed into the end cap of required size.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210355184.4A CN102927552B (en) | 2012-09-23 | 2012-09-23 | Shockproof strip assembly for steam generator of nuclear power unit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210355184.4A CN102927552B (en) | 2012-09-23 | 2012-09-23 | Shockproof strip assembly for steam generator of nuclear power unit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102927552A true CN102927552A (en) | 2013-02-13 |
| CN102927552B CN102927552B (en) | 2014-08-20 |
Family
ID=47642420
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210355184.4A Active CN102927552B (en) | 2012-09-23 | 2012-09-23 | Shockproof strip assembly for steam generator of nuclear power unit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102927552B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104048699A (en) * | 2014-06-23 | 2014-09-17 | 梧州恒声电子科技有限公司 | Method for controlling wires and sticks of T iron class |
| CN104089644A (en) * | 2014-06-23 | 2014-10-08 | 梧州恒声电子科技有限公司 | Control process for T iron type wire bar |
| CN111618120A (en) * | 2020-05-21 | 2020-09-04 | 东莞市万欣金属制品有限公司 | Production method for improving strength of 316L stainless steel bar |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4747373A (en) * | 1986-04-24 | 1988-05-31 | Westinghouse Electric Corp. | Method and apparatus for minimizing antivibration bar gaps of a steam generator |
| US4991645A (en) * | 1988-06-20 | 1991-02-12 | Westinghouse Electric Corp. | Steam generator tube antivibration apparatus |
| CN2562025Y (en) * | 2002-07-02 | 2003-07-23 | 上海汽车空调配件有限公司 | Tubing for threaded joint |
| CN202037426U (en) * | 2011-04-01 | 2011-11-16 | 上海电气核电设备有限公司 | Auxiliary anti-vibration strip assembly tooling for steam generator tube bundle |
| CN202065989U (en) * | 2011-05-10 | 2011-12-07 | 江苏新华合金电器有限公司 | Shockproof strip component used for steam generator of nuclear power station |
| US20120087720A1 (en) * | 2010-10-06 | 2012-04-12 | Mitsubishi Heavy Industries, Ltd. | Dissimilar material joint structure |
-
2012
- 2012-09-23 CN CN201210355184.4A patent/CN102927552B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4747373A (en) * | 1986-04-24 | 1988-05-31 | Westinghouse Electric Corp. | Method and apparatus for minimizing antivibration bar gaps of a steam generator |
| US4991645A (en) * | 1988-06-20 | 1991-02-12 | Westinghouse Electric Corp. | Steam generator tube antivibration apparatus |
| CN2562025Y (en) * | 2002-07-02 | 2003-07-23 | 上海汽车空调配件有限公司 | Tubing for threaded joint |
| US20120087720A1 (en) * | 2010-10-06 | 2012-04-12 | Mitsubishi Heavy Industries, Ltd. | Dissimilar material joint structure |
| CN202037426U (en) * | 2011-04-01 | 2011-11-16 | 上海电气核电设备有限公司 | Auxiliary anti-vibration strip assembly tooling for steam generator tube bundle |
| CN202065989U (en) * | 2011-05-10 | 2011-12-07 | 江苏新华合金电器有限公司 | Shockproof strip component used for steam generator of nuclear power station |
Non-Patent Citations (1)
| Title |
|---|
| 盛旭婷: "压水堆蒸汽发生器的制造", 《装备机械》, 31 December 2010 (2010-12-31) * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104048699A (en) * | 2014-06-23 | 2014-09-17 | 梧州恒声电子科技有限公司 | Method for controlling wires and sticks of T iron class |
| CN104089644A (en) * | 2014-06-23 | 2014-10-08 | 梧州恒声电子科技有限公司 | Control process for T iron type wire bar |
| CN111618120A (en) * | 2020-05-21 | 2020-09-04 | 东莞市万欣金属制品有限公司 | Production method for improving strength of 316L stainless steel bar |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102927552B (en) | 2014-08-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN102794608B (en) | Anti-vibration strip component of steam generator of AP1000 nuclear power unit | |
| CN102927552B (en) | Shockproof strip assembly for steam generator of nuclear power unit | |
| CN103801903A (en) | Preparation method for anti-vibration bar assembly of steam generator of CAP1000 nuclear power unit | |
| CN102764966B (en) | Method for producing vibration-resistant bar assembly of AP1000 nuclear power generating set steam generator | |
| CN103659173B (en) | The end cap of the antivibration bar assembly of nuclear power generating sets steam generator | |
| JP5672215B2 (en) | Surface processing crack sensitivity evaluation method and apparatus | |
| CN103801902B (en) | The anti-vibration bar assembly of CAP1000 nuclear power generating sets steam generator | |
| CN103934646B (en) | A kind of preparation method of Shockproof strip assembly for steam generator of nuclear power unit | |
| CN103056603B (en) | Preparation method for vibration-proof strip assembly for CAP1400 nuclear power generating set vapor generator | |
| CN103659172B (en) | Prepare the method for the anti-vibration bar of nuclear power generating sets steam generator | |
| CN103659170B (en) | Prepare the method for the antivibration bar assembly of nuclear power generating sets | |
| CN112371886B (en) | Forging method of large-size titanium alloy bar blank for gas cylinder | |
| CN103659169B (en) | A kind of method of the anti-vibration bar assembly preparing nuclear power generating sets | |
| CN103921079B (en) | The preparation method of anti-vibration bar assembly | |
| CN103921080B (en) | A kind of preparation method of nuclear power generating sets steam generator anti-vibration bar assembly | |
| CN103934645B (en) | A kind of preparation method of the anti-vibration bar bar in anti-vibration bar assembly | |
| CN103934647B (en) | The preparation method of the anti-vibration bar assembly of steam generator | |
| CN103921083B (en) | Preparation method of the steam generator with antivibration bar assembly | |
| CN103921082B (en) | A kind of preparation method of antivibration bar assembly | |
| CN202846099U (en) | Vibration-proof bar component of access point (AP) 1000 nuclear power unit vapor generator | |
| JP2005271000A (en) | Method for producing high nickel alloy steel plate | |
| RU2531077C2 (en) | Production of mandrels for pipe rolling mills | |
| Liu et al. | Twinning in weld HAZ of ZK21 commercial magnesium alloy | |
| Zhang | Study on Impacts of the Power Spinning Process on the Properties of Hastelloy C-276 | |
| Hahn et al. | Cladding tube manufacturing technology |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |