CN111014314A - Titanium tube production and processing method - Google Patents
Titanium tube production and processing method Download PDFInfo
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- CN111014314A CN111014314A CN201911185241.7A CN201911185241A CN111014314A CN 111014314 A CN111014314 A CN 111014314A CN 201911185241 A CN201911185241 A CN 201911185241A CN 111014314 A CN111014314 A CN 111014314A
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- titanium
- pickling
- washing
- tube
- drying
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
- B21B45/02—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for lubricating, cooling, or cleaning
- B21B45/0239—Lubricating
- B21B45/0242—Lubricants
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B45/00—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
- B21B45/02—Devices for surface or other treatment of work, specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills for lubricating, cooling, or cleaning
- B21B45/0269—Cleaning
-
- 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
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- 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
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Lubricants (AREA)
- Cleaning And De-Greasing Of Metallic Materials By Chemical Methods (AREA)
Abstract
The invention discloses a titanium tube production and processing method, which comprises the following steps: forging the titanium cast ingot into a tube blank, and carrying out surface treatment on the tube blank; rolling the surface-treated tube blank for the first time to form a titanium tube, and removing oil after the first rolling; carrying out first pickling after oil removal, washing the titanium pipe after pickling, drying after washing, annealing after drying, and straightening the titanium pipe after annealing; the invention has the beneficial effects that: the titanium pipe needs to be turned over by 90 degrees during rolling, so that the whole titanium pipe is comprehensively processed, and the symmetrical cracks are reduced; with 23-27% HNO3+2-4% HF + H2Taking the solution of O as a pickling solution, pickling for 8-18min at 10-30 ℃, and enabling the titanium tube to enter the pickling solution for reaction more stably; after acid washing, washing and drying are carried out, which is helpful for improving the plasticity of the titanium tube and avoiding the titanium tube from being rolledHydrogen embrittlement occurs while improving the lubricity.
Description
Technical Field
The invention belongs to the technical field of titanium tube production and processing, and particularly relates to a titanium tube production and processing method.
Background
With the rapid development of modern science and technology and the requirement of national economic construction, the demand of each industrial department for various titanium pipes is increasing day by day, and the requirements for the specification and the technology of the titanium pipes are higher and higher. Particularly, with the demand of market economic development, various industries require more titanium pipes with various specifications. Although the applications of titanium pipes vary, the overall requirements for titanium pipes are consistent, i.e., both the machining conditions and the end use require that the titanium pipes have the required dimensional specifications, precision, corresponding properties, surface finish, and other quality specifications for the application. Whether the quality of the titanium tube can meet various requirements of each user unit on the titanium tube or not is directly related to economic benefits of users or processing industries.
The titanium tube has light weight, high strength and excellent mechanical performance. The heat exchanger is widely applied to heat exchange equipment, such as a shell and tube heat exchanger, a coil heat exchanger, a coiled tube heat exchanger, a condenser, an evaporator, a conveying pipeline and the like. Many nuclear power industries use titanium tubes as the standard tubes of their units.
The existing titanium pipe production and processing has the following defects:
1. the inner surface is easy to crack in production, and the yield is low;
2. the cleanliness of pickling is insufficient.
Disclosure of Invention
The invention aims to provide a titanium tube production and processing method, which aims to solve the problems that the inner surface is easy to crack and the yield is low in the production process proposed in the background technology; there is a problem that cleanliness of pickling is insufficient.
In order to achieve the purpose, the invention provides the following technical scheme: a titanium tube production and processing method comprises the following steps:
the method comprises the following steps: forging the titanium cast ingot into a tube blank, and carrying out surface treatment on the tube blank;
step two: rolling the surface-treated tube blank for the first time to form a titanium tube, and removing oil after the first rolling;
step three: carrying out first pickling after oil removal, washing the titanium pipe after pickling, drying after washing, annealing after drying, and straightening the titanium pipe after annealing;
step four: pickling the titanium pipe again, washing the titanium pipe after pickling, drying the titanium pipe after washing, rolling the titanium pipe for the second time after drying, removing oil from the rolled finished titanium pipe, pickling after removing oil, washing the titanium pipe after pickling, drying after washing, annealing after drying, and straightening the titanium pipe after annealing;
step five: and (4) pickling the titanium pipe after straightening, repeating the steps, and rolling for six times to obtain a finished product.
As a preferable technical scheme of the invention, the solution for acid washing comprises the following components in percentage by weight: 23-27% of HNO3+2-4% HF + H2O。
As a preferred technical scheme of the invention, the solution temperature is 10-30 ℃, and the pickling time is 8-18 min.
As a preferable technical scheme of the invention, MoS2 lubricant is coated on the inner wall and the outer wall of the pierced billet during rolling.
As a preferred technical solution of the present invention, the titanium tube needs to be turned over by 90 ° during the rolling.
As a preferable technical scheme of the invention, the water content of the dried product is less than 8 percent after washing.
The invention also comprises coping, wherein the coping is arranged between annealing and straightening.
Compared with the prior art, the invention has the beneficial effects that:
(1) MoS2 lubricant is coated on the inner wall and the outer wall of the pierced billet during rolling, chlorinated paraffin is strictly forbidden to be used as the lubricant, so that the titanium tube is prevented from being corroded due to the reaction of high temperature generated by the tube and chloride ions in the rolling process, and the yield of the titanium tube is better ensured;
(2) the titanium pipe needs to be turned over by 90 degrees during rolling, so that the whole titanium pipe is comprehensively processed, and the symmetrical cracks are reduced;
(3) with 23-27% HNO3+2-4% HF + H2Taking the solution of O as a pickling solution, pickling for 8-18min at 10-30 ℃, and enabling the titanium tube to enter the pickling solution for reaction more stably;
(4) after acid washing, washing and drying are carried out, which is beneficial to improving the plasticity of the titanium tube, avoiding the hydrogen embrittlement phenomenon of the titanium tube during rolling and improving the lubricating property.
Drawings
FIG. 1 is a process flow diagram of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
Referring to fig. 1, the present invention provides a technical solution: a titanium tube production and processing method comprises the following steps:
the method comprises the following steps: forging the titanium cast ingot into a tube blank, and carrying out surface treatment on the tube blank;
step two: rolling the surface-treated tube blank for the first time to form a titanium tube, and removing oil after the first rolling;
step three: carrying out first pickling after oil removal, washing the titanium pipe after pickling, drying after washing, annealing after drying, and straightening the titanium pipe after annealing;
step four: pickling the titanium pipe again, washing the titanium pipe after pickling, drying the titanium pipe after washing, rolling the titanium pipe for the second time after drying, removing oil from the rolled finished titanium pipe, pickling after removing oil, washing the titanium pipe after pickling, drying after washing, annealing after drying, and straightening the titanium pipe after annealing;
step five: and (4) pickling the titanium pipe after straightening, repeating the steps, and rolling for six times to obtain a finished product.
In this embodiment, the ratio of the pickling solution is preferably as follows: 23% HNO3+2% HF + H2O。
In this embodiment, the solution temperature is preferably 10 ℃ and the pickling time is preferably 18 min.
In this embodiment, it is preferable that MoS2 lubricant is coated on the inner and outer walls of the pierced billet during rolling, and chlorinated paraffin is strictly prohibited to be used as the lubricant, so as to prevent corrosion of the titanium tube caused by reaction between the tube and chloride ions due to high temperature generated during rolling.
In this embodiment, preferably, the titanium tube needs to be turned over by 90 ° during rolling, so that the whole titanium tube is completely processed, which is helpful for reducing symmetric cracks.
In this embodiment, it is preferable that the water content after washing is less than 8%.
In this embodiment, preferably, the method further comprises coping, and coping is placed between annealing and straightening.
The titanium tube after acid washing is washed and dried, and after the titanium tube is washed in acid solution, although the purpose of removing an oxide layer is achieved, part of residual acid exists on the surface of the titanium tube when the surface of the titanium tube is corroded by acid, and if the part of residual acid is not removed, part of hydrogen is diffused into a titanium tube matrix under the chemical action of the residual acid, so that the plasticity of the titanium tube is reduced. Meanwhile, the residual acid on the surface of the titanium pipe can lead to premature wear of a roller during rolling and waste of the titanium pipe. The drying aims to timely drive out hydrogen atoms in metal lattices so as to avoid the hydrogen embrittlement phenomenon formed during rolling of the titanium tube and improve the lubricating property.
Example 2
Referring to fig. 1, the present invention provides a technical solution: a titanium tube production and processing method comprises the following steps:
the method comprises the following steps: forging the titanium cast ingot into a tube blank, and carrying out surface treatment on the tube blank;
step two: rolling the surface-treated tube blank for the first time to form a titanium tube, and removing oil after the first rolling;
step three: carrying out first pickling after oil removal, washing the titanium pipe after pickling, drying after washing, annealing after drying, and straightening the titanium pipe after annealing;
step four: pickling the titanium pipe again, washing the titanium pipe after pickling, drying the titanium pipe after washing, rolling the titanium pipe for the second time after drying, removing oil from the rolled finished titanium pipe, pickling after removing oil, washing the titanium pipe after pickling, drying after washing, annealing after drying, and straightening the titanium pipe after annealing;
step five: and (4) pickling the titanium pipe after straightening, repeating the steps, and rolling for six times to obtain a finished product.
In this embodiment, the ratio of the pickling solution is preferably as follows: 25% HNO3+3% HF + H2O。
In this embodiment, the solution temperature is preferably 20 ℃ and the pickling time is preferably 13 min.
In this embodiment, it is preferable that MoS2 lubricant is coated on the inner and outer walls of the pierced billet during rolling, and chlorinated paraffin is strictly prohibited to be used as the lubricant, so as to prevent corrosion of the titanium tube caused by reaction between the tube and chloride ions due to high temperature generated during rolling.
In this embodiment, preferably, the titanium tube needs to be turned over by 90 ° during rolling, so that the whole titanium tube is completely processed, which is helpful for reducing symmetric cracks.
In this embodiment, it is preferable that the water content after washing is less than 8%.
In this embodiment, preferably, the method further comprises coping, and coping is placed between annealing and straightening.
The titanium tube after acid washing is washed and dried, and after the titanium tube is washed in acid solution, although the purpose of removing an oxide layer is achieved, part of residual acid exists on the surface of the titanium tube when the surface of the titanium tube is corroded by acid, and if the part of residual acid is not removed, part of hydrogen is diffused into a titanium tube matrix under the chemical action of the residual acid, so that the plasticity of the titanium tube is reduced. Meanwhile, the residual acid on the surface of the titanium pipe can lead to premature wear of a roller during rolling and waste of the titanium pipe. The drying aims to timely drive out hydrogen atoms in metal lattices so as to avoid the hydrogen embrittlement phenomenon formed during rolling of the titanium tube and improve the lubricating property.
Example 3
Referring to fig. 1, the present invention provides a technical solution: a titanium tube production and processing method comprises the following steps:
the method comprises the following steps: forging the titanium cast ingot into a tube blank, and carrying out surface treatment on the tube blank;
step two: rolling the surface-treated tube blank for the first time to form a titanium tube, and removing oil after the first rolling;
step three: carrying out first pickling after oil removal, washing the titanium pipe after pickling, drying after washing, annealing after drying, and straightening the titanium pipe after annealing;
step four: pickling the titanium pipe again, washing the titanium pipe after pickling, drying the titanium pipe after washing, rolling the titanium pipe for the second time after drying, removing oil from the rolled finished titanium pipe, pickling after removing oil, washing the titanium pipe after pickling, drying after washing, annealing after drying, and straightening the titanium pipe after annealing;
step five: and (4) pickling the titanium pipe after straightening, repeating the steps, and rolling for six times to obtain a finished product.
In this embodiment, the ratio of the pickling solution is preferably as follows: 27% HNO3+4% HF + H2O。
In this embodiment, the solution temperature is preferably 30 ℃ and the acid washing time is preferably 8 min.
In this embodiment, it is preferable that MoS2 lubricant is coated on the inner and outer walls of the pierced billet during rolling, and chlorinated paraffin is strictly prohibited to be used as the lubricant, so as to prevent corrosion of the titanium tube caused by reaction between the tube and chloride ions due to high temperature generated during rolling.
In this embodiment, preferably, the titanium tube needs to be turned over by 90 ° during rolling, so that the whole titanium tube is completely processed, which is helpful for reducing symmetric cracks.
In this embodiment, it is preferable that the water content after washing is less than 8%.
In this embodiment, preferably, the method further comprises coping, and coping is placed between annealing and straightening.
The titanium tube after acid washing is washed and dried, and after the titanium tube is washed in acid solution, although the purpose of removing an oxide layer is achieved, part of residual acid exists on the surface of the titanium tube when the surface of the titanium tube is corroded by acid, and if the part of residual acid is not removed, part of hydrogen is diffused into a titanium tube matrix under the chemical action of the residual acid, so that the plasticity of the titanium tube is reduced. Meanwhile, the residual acid on the surface of the titanium pipe can lead to premature wear of a roller during rolling and waste of the titanium pipe. The drying aims to timely drive out hydrogen atoms in metal lattices so as to avoid the hydrogen embrittlement phenomenon formed during rolling of the titanium tube and improve the lubricating property.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (7)
1. A titanium tube production and processing method is characterized in that: the processing method comprises the following steps:
the method comprises the following steps: forging the titanium cast ingot into a tube blank, and carrying out surface treatment on the tube blank;
step two: rolling the surface-treated tube blank for the first time to form a titanium tube, and removing oil after the first rolling;
step three: carrying out first pickling after oil removal, washing the titanium pipe after pickling, drying after washing, annealing after drying, and straightening the titanium pipe after annealing;
step four: pickling the titanium pipe again, washing the titanium pipe after pickling, drying the titanium pipe after washing, rolling the titanium pipe for the second time after drying, removing oil from the rolled finished titanium pipe, pickling after removing oil, washing the titanium pipe after pickling, drying after washing, annealing after drying, and straightening the titanium pipe after annealing;
step five: and (4) pickling the titanium pipe after straightening, repeating the steps, and rolling for six times to obtain a finished product.
2. The titanium tube production and processing method according to claim 1, wherein: the solution for acid washing comprises the following components in percentage by weight: 23-27% of HNO3+2-4% HF + H2O。
3. The titanium tube production and processing method according to claim 2, wherein: the solution temperature is 10-30 ℃, and the pickling time is 8-18 min.
4. The titanium tube production and processing method according to claim 1, wherein: and MoS2 lubricant is coated on the inner wall and the outer wall of the pierced billet during the rolling.
5. The titanium tube production and processing method according to claim 1, wherein: and the titanium pipe needs to be turned over for 90 degrees during rolling.
6. The titanium tube production and processing method according to claim 1, wherein: after washing, the water content after drying is less than 8 percent.
7. The titanium tube production and processing method according to claim 1, wherein: also comprises coping, and coping is arranged between annealing and straightening.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911185241.7A CN111014314A (en) | 2019-11-27 | 2019-11-27 | Titanium tube production and processing method |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911185241.7A CN111014314A (en) | 2019-11-27 | 2019-11-27 | Titanium tube production and processing method |
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| CN111014314A true CN111014314A (en) | 2020-04-17 |
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| CN201911185241.7A Pending CN111014314A (en) | 2019-11-27 | 2019-11-27 | Titanium tube production and processing method |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111745354A (en) * | 2020-06-01 | 2020-10-09 | 张家港海岸钛业有限公司 | Titanium alloy thick-wall pipe machining method |
| CN114603307A (en) * | 2020-12-03 | 2022-06-10 | 无锡苏嘉法斯特汽车零配件有限公司 | Method for processing small-diameter thick-wall pipe for automobile shock absorber |
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| JPH0970604A (en) * | 1995-07-05 | 1997-03-18 | Nippon Steel Corp | Manufacture of titanium-based seamless pipe excellent in prevention of occurrence of rolling flaw |
| CN101824564A (en) * | 2009-06-03 | 2010-09-08 | 东港市东方高新金属材料有限公司 | Titanium alloy TC4 cold-rolled tube and production method thereof |
| 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 |
| CN102615138A (en) * | 2012-03-30 | 2012-08-01 | 西北有色金属研究院 | Method for manufacturing titanium pipe |
| CN110972521B (en) * | 2011-07-26 | 2014-03-05 | 西北有色金属研究院 | Preparation method of near α type low-temperature titanium alloy pipe |
-
2019
- 2019-11-27 CN CN201911185241.7A patent/CN111014314A/en active Pending
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|---|---|---|---|---|
| JPH0970604A (en) * | 1995-07-05 | 1997-03-18 | Nippon Steel Corp | Manufacture of titanium-based seamless pipe excellent in prevention of occurrence of rolling flaw |
| CN101824564A (en) * | 2009-06-03 | 2010-09-08 | 东港市东方高新金属材料有限公司 | Titanium alloy TC4 cold-rolled tube and production method thereof |
| 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 |
| CN110972521B (en) * | 2011-07-26 | 2014-03-05 | 西北有色金属研究院 | Preparation method of near α type low-temperature titanium alloy pipe |
| CN102615138A (en) * | 2012-03-30 | 2012-08-01 | 西北有色金属研究院 | Method for manufacturing titanium pipe |
Non-Patent Citations (1)
| Title |
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| 东北工学院轧钢教研室: "《轧钢工艺学》", 30 September 1959 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111745354A (en) * | 2020-06-01 | 2020-10-09 | 张家港海岸钛业有限公司 | Titanium alloy thick-wall pipe machining method |
| CN114603307A (en) * | 2020-12-03 | 2022-06-10 | 无锡苏嘉法斯特汽车零配件有限公司 | Method for processing small-diameter thick-wall pipe for automobile shock absorber |
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Application publication date: 20200417 |