CN112044979A - Low-bursting-rate pure titanium seamless tube for metal corrugated tube and production process thereof - Google Patents
Low-bursting-rate pure titanium seamless tube for metal corrugated tube and production process thereof Download PDFInfo
- Publication number
- CN112044979A CN112044979A CN202010604801.4A CN202010604801A CN112044979A CN 112044979 A CN112044979 A CN 112044979A CN 202010604801 A CN202010604801 A CN 202010604801A CN 112044979 A CN112044979 A CN 112044979A
- Authority
- CN
- China
- Prior art keywords
- pipe
- rate
- tube
- finished
- bursting
- 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.)
- Pending
Links
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 title claims abstract description 47
- 239000010936 titanium Substances 0.000 title claims abstract description 45
- 229910052719 titanium Inorganic materials 0.000 title claims abstract description 44
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 25
- 239000002184 metal Substances 0.000 title claims abstract description 25
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 22
- 230000009172 bursting Effects 0.000 claims abstract description 14
- 238000000137 annealing Methods 0.000 claims description 26
- 238000005097 cold rolling Methods 0.000 claims description 25
- 239000013067 intermediate product Substances 0.000 claims description 18
- 238000005096 rolling process Methods 0.000 claims description 16
- 239000000047 product Substances 0.000 claims description 15
- 230000007547 defect Effects 0.000 claims description 12
- 238000003723 Smelting Methods 0.000 claims description 9
- 238000005406 washing Methods 0.000 claims description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 8
- 238000003754 machining Methods 0.000 claims description 6
- 238000005554 pickling Methods 0.000 claims description 6
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims description 4
- 239000002253 acid Substances 0.000 claims description 4
- 238000005520 cutting process Methods 0.000 claims description 4
- 229910017604 nitric acid Inorganic materials 0.000 claims description 4
- 238000004321 preservation Methods 0.000 claims description 4
- 239000002245 particle Substances 0.000 claims description 3
- 238000004381 surface treatment Methods 0.000 claims description 3
- 238000005242 forging Methods 0.000 claims description 2
- 238000002156 mixing Methods 0.000 claims description 2
- 238000007790 scraping Methods 0.000 claims description 2
- 238000002791 soaking Methods 0.000 claims description 2
- 238000000034 method Methods 0.000 abstract description 37
- 238000002360 preparation method Methods 0.000 abstract description 9
- 230000008569 process Effects 0.000 description 24
- 239000000463 material Substances 0.000 description 11
- 229910001069 Ti alloy Inorganic materials 0.000 description 10
- 239000012535 impurity Substances 0.000 description 9
- 238000003466 welding Methods 0.000 description 8
- 238000003672 processing method Methods 0.000 description 6
- 238000005204 segregation Methods 0.000 description 6
- 239000010935 stainless steel Substances 0.000 description 5
- 229910001220 stainless steel Inorganic materials 0.000 description 5
- 230000001276 controlling effect Effects 0.000 description 4
- 238000013016 damping Methods 0.000 description 4
- 238000006073 displacement reaction Methods 0.000 description 4
- 238000005553 drilling Methods 0.000 description 4
- 238000001192 hot extrusion Methods 0.000 description 4
- 229910052799 carbon Inorganic materials 0.000 description 3
- 239000013078 crystal Substances 0.000 description 3
- 238000009826 distribution Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 239000004568 cement Substances 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 230000002950 deficient Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005272 metallurgy Methods 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 238000007789 sealing Methods 0.000 description 2
- 238000004062 sedimentation Methods 0.000 description 2
- 238000009987 spinning Methods 0.000 description 2
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 2
- 229910052721 tungsten Inorganic materials 0.000 description 2
- 239000010937 tungsten Substances 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 description 1
- NRTOMJZYCJJWKI-UHFFFAOYSA-N Titanium nitride Chemical compound [Ti]#N NRTOMJZYCJJWKI-UHFFFAOYSA-N 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000003889 chemical engineering Methods 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 150000001247 metal acetylides Chemical class 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 239000011733 molybdenum Substances 0.000 description 1
- 229910052758 niobium Inorganic materials 0.000 description 1
- 239000010955 niobium Substances 0.000 description 1
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 description 1
- 150000004767 nitrides Chemical class 0.000 description 1
- 229910052755 nonmetal Inorganic materials 0.000 description 1
- 230000006911 nucleation Effects 0.000 description 1
- 238000010899 nucleation Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- -1 oxides Chemical compound 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 238000004886 process control Methods 0.000 description 1
- 238000001953 recrystallisation Methods 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 238000005482 strain hardening Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C37/00—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape
- B21C37/06—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape of tubes or metal hoses; Combined procedures for making tubes, e.g. for making multi-wall tubes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
- B21B37/78—Control of tube rolling
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P23/00—Machines or arrangements of machines for performing specified combinations of different metal-working operations not covered by a single other subclass
- B23P23/04—Machines or arrangements of machines for performing specified combinations of different metal-working operations not covered by a single other subclass for both machining and other metal-working operations
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/08—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for tubular bodies or pipes
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
- C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
- C22F1/16—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of other metals or alloys based thereon
- C22F1/18—High-melting or refractory metals or alloys based thereon
- C22F1/183—High-melting or refractory metals or alloys based thereon of titanium or alloys based thereon
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G1/00—Cleaning or pickling metallic material with solutions or molten salts
- C23G1/02—Cleaning or pickling metallic material with solutions or molten salts with acid solutions
- C23G1/10—Other heavy metals
- C23G1/106—Other heavy metals refractory metals
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23G—CLEANING OR DE-GREASING OF METALLIC MATERIAL BY CHEMICAL METHODS OTHER THAN ELECTROLYSIS
- C23G3/00—Apparatus for cleaning or pickling metallic material
- C23G3/04—Apparatus for cleaning or pickling metallic material for cleaning pipes
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Organic Chemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Optics & Photonics (AREA)
- Heat Treatment Of Steel (AREA)
Abstract
The invention relates to a low-bursting-rate pure titanium seamless tube for a metal corrugated tube and a production process thereof. The method is characterized in that: the seamless tube has the grain size of 6-7 grade, the tensile strength of 300MPa to Rm of 400MPa, the yield strength of 180MPa to Rp0.2 of 310MPa, the elongation of 50% or more, the wall thickness of 5% t, the ultimate flaring rate of 60% or more and the bursting rate of 3% or less. The pure titanium seamless pipe prepared by the method has the advantages that the grain size reaches 6-7 grades, the room-temperature elongation rate reaches more than 50%, the wall thickness deviation is controlled to be +/-5% t, the ultimate flaring rate reaches more than 60%, and the bursting rate in the subsequent corrugated pipe preparation can be below 3%.
Description
Technical Field
The invention relates to a low-bursting-rate pure titanium seamless tube for a metal corrugated tube and a production process thereof.
Background
The metal corrugated pipe is a flexible, thin-walled and transversely corrugated pipe shell part, can generate axial displacement, angular displacement, lateral displacement and combined displacement under the action of external force, can be used as a sensitive element, a damping element, a compensating element, a sealing element, a valve element and a pipeline connecting piece, has the effects of compensating thermal deformation of a pipeline, damping, absorbing sedimentation deformation of the pipeline and the like, and is widely applied to industries such as petrifaction, instruments, aerospace, chemical engineering, electric power, cement, metallurgy and the like. The material for manufacturing the metal corrugated pipe not only needs to have good compatibility with the temperature, the corrosiveness and the like of a working environment, but also needs to have higher strength and longer fatigue life, and meanwhile, the material has better manufacturing manufacturability. The corrugated pipe with smaller diameter is usually made of small-specification seamless pipe, and the corrugated pipe with larger specification is usually made of plate or strip to form a cylinder, then a longitudinal welding seam is formed, and then the corrugated pipe is formed.
The main forming technologies of the metal corrugated pipe comprise hydraulic bulging, mechanical bulging, roll forming, welding forming and the like, wherein compared with other forming technologies, the hydraulic forming has the advantages of uniform deformation, higher corrugation roundness, plump waveform, good surface quality of a finished product, high forming rate and the like, becomes a mainstream technology for forming the metal corrugated pipe, and is mainly used for forming and manufacturing the small-caliber metal corrugated pipe. At present, the main material for manufacturing the metal corrugated pipe is stainless steel, the bursting rate of the corrugated pipe manufactured by the stainless steel is generally below 5%, but the stainless steel corrugated pipe is easy to lose efficacy in a high-temperature and strong-corrosivity working environment. Titanium and titanium alloy become a novel corrugated pipe manufacturing material due to high specific strength, good process performance and excellent corrosion resistance, and the corrugated pipe prepared from titanium and titanium alloy plays an important role in prolonging the service life of equipment and improving the safety and reliability of the equipment. Among them, a pure titanium seamless tube has excellent cold formability, and a U-shaped corrugated tube is generally produced by a cold working method such as hydroforming.
The bursting rate of the U-shaped corrugated pipe prepared from the pure titanium seamless pipe produced in the market by hydraulic bulging (the forming working pressure of the hydraulic bulging is generally 10-13 MPa) reaches about 10 percent, and the reasons are as follows:
(1) the inside of the used blank pipe has metallurgical defects of component segregation or inclusion and the like: the method is influenced by factors such as the distribution uniformity of impurity elements in the titanium sponge, the change of cooling conditions, the shape and the depth of a molten pool in the smelting process, the different distribution coefficients of the impurity elements during solidification and crystallization, and the like, so that the impurity elements are inevitably distributed in the local part of the blank to form segregation; the titanium sponge contains defective titanium blocks such as nitrides and the like or foreign matters such as organic matters and the like, high-melting-point metal or nonmetal compounds brought in the electrode preparation, welding, smelting and the like, and inclusion defects which are obviously different from a matrix structure are formed in a blank due to reasons such as incomplete electrode penetration caused by material falling and the like, the inclusions are generally divided into high-density (such as tungsten, molybdenum, niobium and the like) and low-density (such as titanium nitride, oxides, carbon, carbides, electrode which is not penetrated and the like) inclusions according to density, the melting points of the inclusions are generally high, and the inclusions are difficult to eliminate in smelting. Segregation causes large differences in properties of various parts of the corrugated pipe, and inclusions, particularly low-density inclusions, are usually hard and brittle, so that crack formation and crack propagation in the production and use processes of the corrugated pipe are promoted, and the hydraulic bulging pipe can be cracked.
(2) The elongation of the used blank pipe at room temperature is not high enough: the elongation at room temperature of the pipe is critical to the preparation of the corrugated pipe, and is an important factor influencing the hydroforming limit and the forming working pressure. Generally speaking, the higher the room temperature elongation of the pipe, the larger the allowable deformation degree, the larger the forming limit, and the smaller the forming working pressure, the more favorable the bulging, so the raw material with high elongation is generally selected when selecting the material. The room temperature elongation of the existing pure titanium seamless pipe is not high enough, generally 30% -40%, which is not beneficial to the preparation of corrugated pipes by hydraulic bulging of the pipe.
(3) The wall thickness uniformity of the used blank pipe is not good enough: in the hydraulic bulging process of the metal corrugated pipe, the wall thickness deviation can cause uneven cold hardening at the trough part, the uneven distribution of deformation stress is aggravated, and the cracking is easily caused, so the requirement of the metal corrugated pipe on the uniformity of the wall thickness of the raw material is strict, the requirement is preferably up to +/-5% t (t is the nominal wall thickness), and the wall thickness deviation of the current seamless pipe is generally controlled within the range of +/-10% t.
(4) The processing performance of the used blank pipe is not good enough: the ultimate flaring rate is one of important indexes for measuring the processing performance of the pipe, and the larger the ultimate flaring rate is, the more excellent the processing performance of the pipe is. The texture is the root cause influencing the performance of the pipe, the limit flaring rate of the pipe can be improved by regulating and controlling the circumferential texture of the pipe to be superior to the radial texture, and the high limit flaring rate is beneficial to the hydraulic bulging of the pipe. The limit flaring rate of the existing pure titanium seamless pipe is not high enough, and is generally about 45%.
Disclosure of Invention
The invention aims to provide a low-bursting-rate pure titanium seamless tube for a metal corrugated tube, which has the grain size of 6-7 grades, the room-temperature elongation of more than 50 percent, the wall thickness deviation controlled within +/-5 percent t and the ultimate flaring rate of more than 60 percent, and can realize the bursting rate of less than 3 percent in the subsequent preparation of the corrugated tube.
The second purpose of the invention is to provide a production process of the pure titanium seamless tube.
A low-bursting-rate pure titanium seamless tube for a metal corrugated tube is characterized in that: the seamless tube has the grain size of 6-7 grade, the tensile strength of 300MPa to Rm of 400MPa, the yield strength of 180MPa to Rp0.2 of 310MPa, the elongation of 50% or more, the wall thickness of 5% t, the ultimate flaring rate of 60% or more and the bursting rate of 3% or less.
The production process of the low-bursting-rate pure titanium seamless tube for the metal corrugated tube is characterized by comprising the following steps of:
(1) selecting loose sponge titanium of grade 0 or above grade 0, and smelting to obtain an ingot;
(2) preparing a tube blank: forging and machining the cast ingot to prepare a smooth rod with the thickness of 50-90 mm, and then using a cross rolling puncher to prepare the smooth rod into a tube blank with the specification of the tube blank
(3) Surface treatment of the tube blank: eliminating oxide skin and macroscopic defects on the outer surface of the tube blank;
(4) cold rolling of the intermediate product pipe: cold rolling by using a two-roller tube machine with a large processing rate for 3-5 times, wherein the processing rate of each pass is controlled to be 55-80%, and the Q value is 0.9-1.5; then cold rolling by a 1-2-pass multi-roller mill, wherein the pass processing rate is controlled to be 25-40%, the total processing rate is controlled to be 45-70%, and the rolling Q value is controlled to be 1.8-3;
annealing the intermediate product pipe, wherein the annealing temperature of the intermediate product pipe is 650-700 ℃, and the heat preservation time is 90-120 min;
acid washing and water washing are carried out on the intermediate product pipe: soaking the obtained intermediate product pipe in hot water to remove oil stains, then pickling in a pickling solution, and finally washing with water;
finishing and treating the surface of the intermediate product pipe: straightening the intermediate product pipe by using a straightening machine after each-pass annealing, wherein the straightness of the straightened pipe is less than or equal to 3 mm/m; after straightening, removing the tail of the pipe by using a pipe cutting machine or a sawing machine, and then flatly flattening to ensure that the end part is smooth and has no burrs; rolling the tube blank for one pass, and scraping and repairing the outer surface and boring the inner wall after annealing and straightening to eliminate the visible defect of the outer surface; the unilateral boring amount is 0.3-0.5 mm, so that the inner wall of the pipe is free of any hard particles, metal chips and macroscopic defects;
obtaining a finished product pipe;
(5) annealing of the finished pipe: annealing the obtained finished pipe, wherein the annealing temperature of the finished pipe is 600-700 ℃, and the heat preservation time is 60-120 min;
acid washing the finished pipe: the pickling solution is HF, HNO3 and water according to a certain proportion, namely HF: HNO3：H2O is 3-15: 40-70: mixing at a volume ratio of 100;
finishing and treating the surface of the finished pipe: specifically, a straightening machine is used for straightening the finished pipe after annealing, the straightness of the straightened pipe is less than or equal to 2mm/m, and the straightened finished pipe is ensured to have no waves, straightening lines and the like on the surface; and (3) using a pipe cutting machine or a circular saw to length the finished pipe, and then flatly flattening the end of the finished pipe to ensure that the end of the finished pipe is smooth and has no burrs.
The invention provides a pure titanium seamless pipe and a cold rolling process thereof, which are characterized in that measures such as high-grade sponge titanium, impurity element content, enhanced smelting process control and the like are selected to control and reduce metallurgical defects such as segregation, inclusion and the like, a skew-rolled perforated pipe blank with a certain specification is prepared, a large processing rate of two-roller cold rolling, multi-roller rolling Q value control, surface treatment and a proper vacuum annealing system are adopted, and the prepared finished seamless pipe has uniform tissue, high room-temperature elongation, uniform wall thickness and excellent process performance, and can realize low bursting rate in subsequent corrugated pipe preparation. The pure titanium seamless pipe prepared by the method has the advantages that the grain size reaches 6-7 grades, the room-temperature elongation rate reaches more than 50%, the wall thickness deviation is controlled to be +/-5% t, the ultimate flaring rate reaches more than 60%, and the bursting rate in the subsequent corrugated pipe preparation can be below 3%.
Detailed Description
The technical problems solved by the method and the adopted technical characteristics are mainly as follows:
(1) the ingot has segregation, inclusion and other metallurgical defects as less as possible: the method is characterized in that sponge titanium of grade 0 or above is selected, the content of Fe and O in main impurity elements is uniform, the fluctuation of Fe is within 0.02%, the fluctuation of O is within 0.02%, the fluctuation of C, N content is controlled within 0.01%, the content of impurity elements such as Mn, Mg, Cl and the like is as low as possible, the loose packing density of the sponge titanium is small, the sponge titanium particles are in a sponge shape, the forming performance is good, the quality of pressed electrodes is high, and the stability of the smelting process can be ensured; removing defective titanium blocks and impurities in the titanium sponge through titanium sponge picking; the vacuum plasma welding box is used for welding, so that tungsten electrode pollution, welding line oxidation and nitridation are avoided, and the risk of inclusion brought in the production process is further reduced; one electrode is used in the last smelting, so that the phenomenon that the electrode is not completely melted to form inclusions due to material dropping in the smelting process is avoided; the equipment and on-site cleaning and the production process control are enhanced, and foreign impurities are prevented from being brought in the production process.
(2) The crystal grains are fully crushed by adopting two-roller cold rolling for multiple passes and high processing rate, so that on one hand, the deformation storage energy can be increased, the dislocation density is improved, and on the other hand, the tissue uniformity can be improved; meanwhile, the proper annealing temperature is adopted, the nucleation rate is improved, the recrystallization of crystal grains is promoted to be complete, the room-temperature elongation of the finished pipe can reach more than 50%, and the grain size is 6-7 grade.
(3) Selecting a skew rolling tube blank with the wall thickness deviation within the range of +/-10% t, and controlling the wall thickness deviation of the finished tube to be within the range of +/-5% t by utilizing the deviation rectifying capability of a multi-pass two-roller rolling mill.
(4) The tubular product texture is regulated and controlled by controlling the Q value of two-roller and multi-roller cold rolling, so that the circumferential texture of the tubular product is superior to the axial texture, the tubular product is ensured to have excellent technological performance, and the ultimate flaring rate of the tubular product reaches over 60 percent.
The metal corrugated pipe is used as a sensitive element, a damping element, a compensation element, a sealing element, a valve element and a pipeline connecting piece, has the effects of compensating the thermal deformation of a pipeline, damping, absorbing the sedimentation deformation of the pipeline and the like, and is widely applied to the industries of petrifaction, instruments, aerospace, chemical industry, electric power, cement, metallurgy and the like. The material for manufacturing the metal corrugated pipe not only needs to have good compatibility with the temperature, the corrosiveness and the like of a working environment, but also needs to have higher strength and longer fatigue life, and meanwhile, the material has better manufacturing manufacturability. The corrugated pipe with smaller diameter is usually made of small-specification seamless pipe, and the corrugated pipe with larger specification is usually made of plate or strip to form a cylinder, then a longitudinal welding seam is formed, and then the corrugated pipe is formed. At present, the main material for manufacturing the metal corrugated pipe is stainless steel (such as 0Cr18Ni9, 0Cr18Ni9Ti and the like), but the stainless steel corrugated pipe is easy to lose efficacy in a high-temperature and strong-corrosivity working environment, and titanium alloy become a novel corrugated pipe material due to high specific strength, good process performance and excellent corrosion resistance. At present, the high-strength titanium alloy seamless pipe is manufactured into a corrugated pipe by adopting welding or superplastic forming and other methods, and a U-shaped corrugated pipe is generally manufactured by cold processing methods such as hydraulic bulging and the like due to excellent cold formability of a pure titanium seamless pipe; the corrugated pipe prepared by the cold processing method has high requirements on the internal quality, the tissue uniformity, the room temperature plasticity and the process performance of the seamless pipe. The pure titanium seamless pipe produced in the current market has certain metallurgical defects (segregation or inclusion and the like), has low room temperature plasticity (generally 30-40%), large wall thickness deviation (plus or minus 10 percent t) and poor process performance (for example, the ultimate flaring rate is about 45 percent), so that the pure titanium seamless pipe has high bursting rate (about 10 percent) in the corrugated pipe preparation process.
At present, patents and articles for carrying out cold rolling process research on pure titanium seamless pipes aiming at low bursting rate performance do not exist, and most of the articles and patents related to the pure titanium seamless pipes are titanium and titanium alloy pipes with high standard, high strength and high precision or (ultra) thin and thick walls and other performances. At present, the common processing methods of the titanium and titanium alloy seamless pipes mainly comprise drilling hot extrusion, machining, spinning or rolling, drawing after the drilling hot extrusion, machining or rolling, drawing after oblique rolling perforation and the like, and the methods respectively have unique process characteristics and practical production modes.
Although the titanium and titanium alloy seamless pipes related to the related patents have unique process characteristics and flexible production modes, the deformation, Q value, heat treatment and cold rolling processes in the production process are different, so that the finished pipes have differences in structure uniformity, wall thickness deviation, room temperature plasticity and process performance.
At present, the common processing methods of titanium and titanium alloy seamless pipes mainly comprise methods of drilling hot extrusion, machining, spinning or rolling, drawing after the drilling hot extrusion, machining, rolling or rolling, drawing after cross rolling perforation and the like, most of the methods are only researched for titanium and titanium alloy pipes with large caliber, high straightness, high strength, high precision or thin and thick walls, and the like, and related researches on a pure titanium seamless pipe cold rolling process aiming at low expansion fracture rate performance are not yet carried out. Pure titanium seamless tubes are generally manufactured by cold processing methods such as hydraulic forming, bulging forming and the like, and the corrugated tubes manufactured by the cold processing methods have high requirements on the structural uniformity, plasticity and technological performance of seamless tubes. The pure titanium pipe produced in the current market has certain metallurgical defects, uneven structure, low room temperature elongation and low process performance, so that the burst rate of the seamless pipe for preparing the corrugated pipe in a cold processing mode is high (generally 10%).
Example 1:
low-bursting pure titanium
The cold rolling process of the seamless pipe comprises the following steps: cross piercing
The tube blank is subjected to 3-pass two-roller cold rolling (pass working ratio is controlled to be 55-80%, and Q value is 0.9-1.5) and 1-pass multi-roller cold rolling (pass working ratio is 27.84%, and Q value is 1.87), the annealing temperature of an intermediate product is 650-700 ℃ for 90-120 min, and the annealing temperature of a finished product is 700 x 90 min. The finished product is detected to have the room-temperature tensile strength of 341MPa, the yield strength of 193MPa and the elongation of 60 percent; the ultimate flaring rate reaches 60 percent, and the grain size reaches 6 grades; the burst rate of the corrugated pipe is 2.8 percent.
Example 2:
low-bursting pure titanium
The cold rolling process of the seamless pipe comprises the following steps: cross piercing
The tube blank is subjected to 3-pass two-roller cold rolling (pass reduction rate is controlled to be 55-80%, Q value is 0.9-1.5) and 1-pass multi-roller cold rolling (pass reduction rate is 39.78%, Q value is 2.83), and the intermediate product is annealed at high temperatureThe temperature is 650-700 ℃ multiplied by 90-120 min, and the annealing temperature of the finished product is 650 multiplied by 90 min. The finished product is detected to have the room-temperature tensile strength of 352MPa, the yield strength of 201MPa and the elongation of 66 percent; the ultimate flaring rate reaches 68 percent, and the grain size reaches 7 grades; the burst rate of the corrugated pipe is 2.7 percent.
Example 3:
low-bursting pure titanium
The cold rolling process of the seamless pipe comprises the following steps: cross piercing
The tube blank is subjected to 3-pass two-roller cold rolling (pass working ratio is controlled to be 55-80%, and Q value is 0.9-1.5) and 1-pass multi-roller cold rolling (pass working ratio is 39.56%, and Q value is 1.71), the annealing temperature of an intermediate product is 650-700 ℃ for 90-120 min, and the annealing temperature of a finished product is 650 x 90 min. The finished product is detected to have the room temperature tensile strength of 360MPa, the yield strength of 213MPa and the elongation of 68 percent; the ultimate flaring rate reaches 70%, and the grain size reaches 8 levels; the burst rate of the corrugated pipe is 2.9 percent.
Compared with the best prior art, the pure titanium seamless pipe produced by the method has the advantages of uniform crystal grains, moderate size (the grain size is 6-7 grade), high room-temperature elongation (the elongation is more than or equal to 50%), uniform wall thickness (plus or minus 5 percent t), excellent process performance (the ultimate flaring rate reaches more than 60 percent) and the like, and the burst rate of the prepared metal corrugated pipe can reach less than 3 percent.
The method for preparing the seamless pipe of the corrugated pipe with low bursting rate has the following performance indexes: tensile Properties at room temperature (20 ℃): rm is more than or equal to 300MPa and less than or equal to 400MPa in tensile strength, Rp0.2 is more than or equal to 180MPa in yield strength, and the percentage elongation after fracture is more than or equal to 50 percent. Wall thickness deviation: 5% t. Limiting flaring rate: the flaring rate of the pipe is more than or equal to 60 percent. Grain size: 6-7 grade.
The invention provides a pure titanium seamless pipe product which is applied to the preparation of a metal corrugated pipe, has the grain size of 6-7 grades, high room-temperature elongation (the tensile strength is more than or equal to 300MPa and less than or equal to 400MPa, the yield strength is more than or equal to 180MPa and less than or equal to Rp0.2 and less than or equal to 310MPa, the elongation is more than or equal to 50%), uniform wall thickness (plus or minus 5% t), excellent processing performance (the ultimate flaring rate is more than 60%) and low bursting rate (less than 3%). Selecting loose titanium sponge of 0 grade or above, controlling the fluctuation range of the content of main impurity element Fe within 0.02%, the fluctuation range of the content of O within 0.02%, and the fluctuation range of the content of C, N within 0.01%. The cold rolling process of the pipe comprises the following steps: the large processing rate of the two-roller cold rolling pass is controlled to be 55-80%, and the Q value is 0.9-1.5; the multi-roll cold rolling pass working rate is 25-40%, the total working rate is 45-70%, and the Q value is controlled to be 1.8-3. The pipe vacuum annealing process comprises the following steps: the annealing temperature of the intermediate product is 650-700 ℃; the annealing temperature of the finished product is 600-700 ℃.
Claims (2)
1. The utility model provides a metal corrugated pipe is with pure titanium seamless pipe of low bursting strength which characterized in that: the seamless tube has the grain size of 6-7 grade, the tensile strength of 300MPa to Rm of 400MPa, the yield strength of 180MPa to Rp0.2 of 310MPa, the elongation of 50% or more, the wall thickness of 5% t, the ultimate flaring rate of 60% or more and the bursting rate of 3% or less.
2. The production process of the low-bursting-rate pure titanium seamless tube for the metal corrugated tube is characterized by comprising the following steps of:
(1) selecting loose sponge titanium of grade 0 or above grade 0, and smelting to obtain an ingot;
(2) preparing a tube blank: forging and machining the cast ingot to prepare a smooth rod with the thickness of 50-90 mm, and then using a cross rolling puncher to prepare the smooth rod into a tube blank with the specification of the tube blank
(3) Surface treatment of the tube blank: eliminating oxide skin and macroscopic defects on the outer surface of the tube blank;
(4) cold rolling of the intermediate product pipe: cold rolling by using a two-roller tube machine with a large processing rate for 3-5 times, wherein the processing rate of each pass is controlled to be 55-80%, and the Q value is 0.9-1.5; then cold rolling by a 1-2-pass multi-roller mill, wherein the pass processing rate is controlled to be 25-40%, the total processing rate is controlled to be 45-70%, and the rolling Q value is controlled to be 1.8-3;
annealing the intermediate product pipe, wherein the annealing temperature of the intermediate product pipe is 650-700 ℃, and the heat preservation time is 90-120 min;
acid washing and water washing are carried out on the intermediate product pipe: soaking the obtained intermediate product pipe in hot water to remove oil stains, then pickling in a pickling solution, and finally washing with water;
finishing and treating the surface of the intermediate product pipe: straightening the intermediate product pipe by using a straightening machine after each-pass annealing, wherein the straightness of the straightened pipe is less than or equal to 3 mm/m; after straightening, removing the tail of the pipe by using a pipe cutting machine or a sawing machine, and then flatly flattening to ensure that the end part is smooth and has no burrs; rolling the tube blank for one pass, and scraping and repairing the outer surface and boring the inner wall after annealing and straightening to eliminate the visible defect of the outer surface; the unilateral boring amount is 0.3-0.5 mm, so that the inner wall of the pipe is free of any hard particles, metal chips and macroscopic defects;
obtaining a finished product pipe;
(5) annealing of the finished pipe: annealing the obtained finished pipe, wherein the annealing temperature of the finished pipe is 600-700 ℃, and the heat preservation time is 60-120 min;
acid washing the finished pipe: the pickling solution is HF, HNO3 and water according to a certain proportion, namely HF: HNO3：H2O is 3-15: 40-70: mixing at a volume ratio of 100;
finishing and treating the surface of the finished pipe: specifically, a straightening machine is used for straightening the finished pipe after annealing, the straightness of the straightened pipe is less than or equal to 2mm/m, and the straightened finished pipe is ensured to have no waves, straightening lines and the like on the surface; and (3) using a pipe cutting machine or a circular saw to length the finished pipe, and then flatly flattening the end of the finished pipe to ensure that the end of the finished pipe is smooth and has no burrs.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911401186 | 2019-12-30 | ||
| CN2019114011860 | 2019-12-30 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112044979A true CN112044979A (en) | 2020-12-08 |
Family
ID=73601819
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010604801.4A Pending CN112044979A (en) | 2019-12-30 | 2020-06-29 | Low-bursting-rate pure titanium seamless tube for metal corrugated tube and production process thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112044979A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114717496A (en) * | 2022-03-24 | 2022-07-08 | 太原理工大学 | Boeing hot rolling combined pulse current annealing method for titanium alloy plate |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2364210A1 (en) * | 1973-01-23 | 1974-07-25 | Princeton Metal Systems Corp | METHOD OF MANUFACTURING A MOLDED PART, IN PARTICULAR A PIPE |
| CA2003244A1 (en) * | 1988-11-18 | 1990-05-18 | Atsuhiko Kuroda | Method of manufacturing seamless tube formed of titanium material |
| CN101708511A (en) * | 2007-12-13 | 2010-05-19 | 攀钢集团四川长城特殊钢有限责任公司 | Method for manufacturing pure titanium seamless tubes |
| CN102240890A (en) * | 2011-05-20 | 2011-11-16 | 西部钛业有限责任公司 | Manufacturing method of thick-walled titanium tube |
| CN106493187A (en) * | 2016-10-27 | 2017-03-15 | 南京宝泰特种材料股份有限公司 | A kind of heavy caliber thick wall titanium and its low-cost manufacture method of alloy seamless tubing |
| CN107052076A (en) * | 2016-11-28 | 2017-08-18 | 安徽宝泰特种材料有限公司 | A kind of method of chuck plug hot rolling heavy caliber titanium or titanium alloy thin-wall seamless pipe |
| CN107234145A (en) * | 2017-07-18 | 2017-10-10 | 攀钢集团研究院有限公司 | The method of pure titanium seamless tubes roll piercing |
| CN107377668A (en) * | 2017-09-22 | 2017-11-24 | 攀钢集团研究院有限公司 | Production method for the pure titanium hollow forging sizings of TA2 |
-
2020
- 2020-06-29 CN CN202010604801.4A patent/CN112044979A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2364210A1 (en) * | 1973-01-23 | 1974-07-25 | Princeton Metal Systems Corp | METHOD OF MANUFACTURING A MOLDED PART, IN PARTICULAR A PIPE |
| CA2003244A1 (en) * | 1988-11-18 | 1990-05-18 | Atsuhiko Kuroda | Method of manufacturing seamless tube formed of titanium material |
| CN101708511A (en) * | 2007-12-13 | 2010-05-19 | 攀钢集团四川长城特殊钢有限责任公司 | Method for manufacturing pure titanium seamless tubes |
| CN102240890A (en) * | 2011-05-20 | 2011-11-16 | 西部钛业有限责任公司 | Manufacturing method of thick-walled titanium tube |
| CN106493187A (en) * | 2016-10-27 | 2017-03-15 | 南京宝泰特种材料股份有限公司 | A kind of heavy caliber thick wall titanium and its low-cost manufacture method of alloy seamless tubing |
| CN107052076A (en) * | 2016-11-28 | 2017-08-18 | 安徽宝泰特种材料有限公司 | A kind of method of chuck plug hot rolling heavy caliber titanium or titanium alloy thin-wall seamless pipe |
| CN107234145A (en) * | 2017-07-18 | 2017-10-10 | 攀钢集团研究院有限公司 | The method of pure titanium seamless tubes roll piercing |
| CN107377668A (en) * | 2017-09-22 | 2017-11-24 | 攀钢集团研究院有限公司 | Production method for the pure titanium hollow forging sizings of TA2 |
Non-Patent Citations (1)
| Title |
|---|
| 杨英丽;卢亚锋;郭荻子;罗媛媛;赵恒章;苏航标;: "氧含量及轧制工艺对纯钛管材性能的影响", 钛工业进展, no. 05, pages 27 - 30 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114717496A (en) * | 2022-03-24 | 2022-07-08 | 太原理工大学 | Boeing hot rolling combined pulse current annealing method for titanium alloy plate |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5141566A (en) | Process for manufacturing corrosion-resistant seamless titanium alloy tubes and pipes | |
| CA2967906C (en) | High-strength thick-walled electric-resistance-welded steel pipe for deep-well conductor casing, method for manufacturing the same, and high-strength thick-walled conductor casing for deep wells | |
| JP6197850B2 (en) | Method for producing duplex stainless steel seamless pipe | |
| WO2010082395A1 (en) | Process for production of duplex stainless steel pipe | |
| JP2003311317A (en) | Method for manufacturing seamless tube | |
| WO2013133076A1 (en) | Method for producing high-strength steel material having excellent sulfide stress cracking resistance | |
| RU2583566C1 (en) | METHOD FOR PRODUCING COLD-DEFORMED SEAMLESS PIPES MADE OF TITANIUM ALLOY Ti-3Al-2,5V | |
| JP6341125B2 (en) | Method for producing duplex stainless steel pipe | |
| CN115667560B (en) | Alloy pipe and method for manufacturing same | |
| WO2010113843A1 (en) | Method for producing high-strength seamless cr-ni alloy pipe | |
| CN113399461B (en) | Method for processing niobium-containing austenitic heat-resistant stainless steel round pipe billet | |
| CN114250414B (en) | Seamless steel pipe for pipeline and preparation method thereof | |
| CN110218940B (en) | High-temperature alloy seamless pipe and preparation method thereof | |
| CN111575450A (en) | Seamless steel pipe and preparation method thereof | |
| CN112718910A (en) | Manufacturing method of large-caliber TC4 titanium alloy thick-wall pipe | |
| JP2000104117A (en) | Production of seamless steel pipe for linepipe excellent in toughness and uniformity of strength | |
| CN112008348B (en) | Manufacturing method of cold-hardened high-strength super dual-phase steel seamless pipe | |
| JP2007196237A (en) | Method for producing seamless steel tube for machine structural component | |
| CN112044979A (en) | Low-bursting-rate pure titanium seamless tube for metal corrugated tube and production process thereof | |
| CN110788141B (en) | Seamless steel tube, manufacturing method and high-pressure gas cylinder thereof | |
| CN111118410A (en) | Thick-wall large-caliber high-steel grade pipeline pipe with thickness of 40-60 mm and manufacturing method thereof | |
| CN111187978A (en) | Phi 559 mm-711 mm large-caliber oblique rolling rotary-expansion seamless pipeline pipe and manufacturing method thereof | |
| JP4462454B1 (en) | Manufacturing method of duplex stainless steel pipe | |
| CN118308666A (en) | Stainless steel pipe and method for manufacturing same | |
| JPH10291008A (en) | Tool for hot making tube and its manufacture |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20201208 |