CN113333598B - Processing method of metal composite pipe - Google Patents
Processing method of metal composite pipe Download PDFInfo
- Publication number
- CN113333598B CN113333598B CN202110688656.7A CN202110688656A CN113333598B CN 113333598 B CN113333598 B CN 113333598B CN 202110688656 A CN202110688656 A CN 202110688656A CN 113333598 B CN113333598 B CN 113333598B
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- Prior art keywords
- metal
- pipe
- temperature
- induction heating
- composite pipe
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- 239000002905 metal composite material Substances 0.000 title claims abstract description 27
- 238000003672 processing method Methods 0.000 title abstract description 6
- 229910052751 metal Inorganic materials 0.000 claims abstract description 56
- 239000002184 metal Substances 0.000 claims abstract description 56
- 230000006698 induction Effects 0.000 claims abstract description 43
- 238000010438 heat treatment Methods 0.000 claims abstract description 34
- 238000000034 method Methods 0.000 claims abstract description 33
- 239000002131 composite material Substances 0.000 claims abstract description 11
- 230000004927 fusion Effects 0.000 claims description 20
- 239000003795 chemical substances by application Substances 0.000 claims description 14
- 230000009471 action Effects 0.000 claims description 6
- 230000002500 effect on skin Effects 0.000 claims description 5
- 230000007704 transition Effects 0.000 claims description 5
- 238000006243 chemical reaction Methods 0.000 claims description 4
- 238000005488 sandblasting Methods 0.000 claims description 3
- 239000011295 pitch Substances 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 abstract description 7
- 230000008569 process Effects 0.000 abstract description 7
- 230000008859 change Effects 0.000 abstract description 3
- 238000010297 mechanical methods and process Methods 0.000 abstract description 3
- 239000007789 gas Substances 0.000 description 12
- 239000010935 stainless steel Substances 0.000 description 8
- 229910001220 stainless steel Inorganic materials 0.000 description 8
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 6
- 229910000975 Carbon steel Inorganic materials 0.000 description 6
- 239000010962 carbon steel Substances 0.000 description 6
- 239000001569 carbon dioxide Substances 0.000 description 3
- 229910002092 carbon dioxide Inorganic materials 0.000 description 3
- 238000005253 cladding Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 238000005096 rolling process Methods 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 229910001335 Galvanized steel Inorganic materials 0.000 description 1
- 229910001566 austenite Inorganic materials 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 238000000354 decomposition reaction Methods 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 239000008397 galvanized steel Substances 0.000 description 1
- ZLNQQNXFFQJAID-UHFFFAOYSA-L magnesium carbonate Chemical compound [Mg+2].[O-]C([O-])=O ZLNQQNXFFQJAID-UHFFFAOYSA-L 0.000 description 1
- 239000001095 magnesium carbonate Substances 0.000 description 1
- 229910000021 magnesium carbonate Inorganic materials 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 230000008961 swelling Effects 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D39/00—Application of procedures in order to connect objects or parts, e.g. coating with sheet metal otherwise than by plating; Tube expanders
- B21D39/04—Application of procedures in order to connect objects or parts, e.g. coating with sheet metal otherwise than by plating; Tube expanders of tubes with tubes; of tubes with rods
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D37/00—Tools as parts of machines covered by this subclass
- B21D37/16—Heating or cooling
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/25—Process efficiency
Abstract
The invention is suitable for the related field of composite pipe production, and provides a processing method of a metal composite pipe, which comprises the following steps: a plurality of medium-frequency induction heating coils are sequentially and evenly arranged among the rotating straight roller ways; placing the metal composite tube with the expansion agent packaged inside on a roller way to rotate and move forwards; sequentially passes through the medium-frequency induction heating coil arranged between the roller ways. The method is characterized in that a plurality of medium-frequency induction heating coils are arranged, the temperature of the heating coils is controlled, and the metal composite pipe can be processed in the process of the metal pipe rotating and advancing, and compared with the metal composite pipe manufactured by other methods, the method has the characteristics of simple process and low cost; by utilizing the expansion of decomposed gas of the expanding agent and the phase change of the metal outer pipe in the heating process, the metal composite pipe manufactured by the method has stronger bonding force and higher comprehensive performance compared with a composite pipe combined by a mechanical method.
Description
Technical Field
The invention belongs to the field related to composite pipe production, and particularly relates to a processing method of a metal composite pipe.
Background
The metal composite steel pipe is a novel composite water supply pipe material which is formed by strongly embedding a galvanized steel pipe, a welded pipe or a seamless steel pipe and a stainless steel pipe with thinner wall thickness, and is a more ideal pipeline upgrading and updating product. It retains the inherent advantages of two different metal materials and complements their inherent disadvantages, thus being convenient, reliable, sanitary and safe in use.
Wherein, the outer base pipe is responsible for the pressure-bearing and the effect that the pipeline rigidity supported, and the interior bushing pipe undertakes effects such as corrosion-resistant, stand wear and tear. The existing methods for manufacturing the metal composite pipe comprise a mechanical rolling method, an explosion cladding method, a drawing cladding method and a hydraulic cladding method. The mechanical rolling method and the drawing composite method have higher requirements on the levelness of linear feeding of mechanical parts in the operation process; the other two methods are relatively complicated to operate and relatively high in manufacturing cost.
Disclosure of Invention
The embodiment of the invention aims to provide a method for processing a metal composite pipe, and aims to solve the problems of complex operation and high manufacturing cost of the existing method for manufacturing the metal composite pipe.
The embodiment of the invention is realized in such a way that a method for processing a metal composite pipe comprises the following steps:
a plurality of medium-frequency induction heating coils are evenly arranged between the rotating straight roller ways in sequence; the front multiple intermediate frequency induction heating coils are preheating coils, and the last stage intermediate frequency induction heating coil is a high-temperature pressure fusion induction coil;
placing the metal composite tube with the expansion agent packaged inside on a roller way to rotate and move forwards;
sequentially passing through a medium-frequency induction heating coil arranged between the roller ways;
and fusing the metal interface pressure of the metal inner pipe and the metal outer pipe.
Preferably, the induction temperature of the front plurality of preheating coils is set to a temperature at which the swelling agent is completely decomposed; and setting the induction temperature of the last-stage high-temperature pressure fusion induction coil as the high-temperature pressure fusion temperature.
Preferably, the intermediate frequency induction heating coil sequentially arranged between the roller ways specifically includes:
after passing through a plurality of preheating coils, the expanding agent is heated to decompose gas;
under the condition of the same temperature and the same gas expansion pressure, the high-temperature pressure fusion temperature is reached when the induction coil is fused by high-temperature pressure;
the expansion force of the metal inner pipe and decomposed gas is relied on to force the metal inner pipe to expand and generate plastic deformation, the metal inner pipe is tightly attached to the inner wall of the metal outer pipe and generates interface reaction, and simultaneously, the metal interface of the metal inner pipe and the metal outer pipe is fused under the action of medium-frequency induced current skin effect.
Preferably, the inner wall of the metal outer pipe is subjected to sand blasting.
Preferably, the high-temperature pressure fusion temperature is the phase transition temperature of the metal outer pipe.
Preferably, the sum of the pitches of the plurality of induction heating coils is equal to the length of the clad pipe.
According to the processing method of the metal composite pipe provided by the embodiment of the invention, the plurality of medium-frequency induction heating coils are arranged, and the temperature of the heating coils is controlled, so that the metal composite pipe can be processed in the process of the metal pipe rotating and advancing, and compared with the metal composite pipe manufactured by other methods, the processing method of the metal composite pipe has the characteristics of simple process and low manufacturing cost; by utilizing the expansion of decomposed gas of the expanding agent and the phase change of the metal outer pipe in the heating process, the metal composite pipe manufactured by the method has stronger bonding force and higher comprehensive performance compared with a composite pipe combined by a mechanical method.
Drawings
Fig. 1 is a schematic structural diagram of a metal-clad composite pipe according to an embodiment of the present invention;
FIG. 2 is a schematic structural diagram of a part of a processing apparatus for a metal-clad composite pipe according to an embodiment of the present invention;
1. an outer tube; 2. an inner tube; 3. rotating the straight roller way; 4. preheating a coil; 5. high temperature pressure fuses the induction coil.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Specific implementations of the present invention are described in detail below with reference to specific embodiments.
As shown in fig. 1 and fig. 2, a block diagram of a method for processing a metal composite pipe according to an embodiment is provided, where the method includes:
a plurality of medium-frequency induction heating coils are evenly arranged between the rotating straight roller ways in sequence; the front multiple intermediate frequency induction heating coils are preheating coils, and the last stage intermediate frequency induction heating coil is a high-temperature pressure fusion induction coil; wherein the sum of the distances between the induction heating coils is equal to the length of the composite pipe.
Placing the metal composite pipe with the expansion agent packaged inside on a roller way to rotate and move forwards; wherein the expanding agent decomposes into gases during heating, for example a carbonate expanding agent, and carbon dioxide under heating; the metal inner tube is sealed at both ends so that the expanding agent is in a closed space. The metal inner pipe in the metal composite pipe is preferably a stainless steel inner pipe, and the metal outer pipe is selected from a carbon steel outer pipe. The purpose of heating to decompose the carbonate and expand the generated carbon dioxide gas is to cause the stainless steel inner tube to be plastically deformed under the action of high temperature and gas expansion pressure.
Sequentially passes through the medium-frequency induction heating coil arranged between the roller ways. The purpose of adopting medium-frequency induction heating is to utilize the skin effect of induced current to gather a large amount of current on the metal surface, the current generates a large amount of heat, and the heat can be conducted into the metal, so that the integral temperature of the metal is raised, and the fusion at the rear side is facilitated.
And fusing the metal interface pressure of the metal inner pipe and the metal outer pipe.
In one case of this embodiment, the method sets a plurality of medium frequency induction heating coils, and controls the temperature of the heating coils, so that the metal composite tube can be processed in the process of the metal tube rotating and advancing, and compared with the metal composite tubes manufactured by other methods, the method has the characteristics of simple process and low cost; by utilizing the expansion of the decomposed gas of the expanding agent and the phase change of the metal outer pipe in the heating process, the metal composite pipe manufactured by the method has stronger bonding force and higher comprehensive performance compared with a composite pipe bonded by a mechanical method.
In one case of this embodiment, as shown in fig. 2, the induction temperature of the front plurality of preheating coils is set to a temperature at which the expansion agent is completely decomposed, e.g., the decomposition temperature of magnesium carbonate is 270 ℃; and setting the induction temperature of the last-stage high-temperature pressure fusion induction coil as the high-temperature pressure fusion temperature. The purpose of sequentially arranging the plurality of medium-frequency induction heating coils in the front and keeping the same induction temperature is to ensure the pressure balance of the expansion of carbon dioxide gas in the closed space to all parts of the inner wall of the stainless steel pipe before the metal pipe enters the last stage of induction coil.
The high-temperature pressure fusion temperature is the phase transition temperature of the metal outer pipe, and if the phase transition temperatures (which are the inherent physical properties of metals) of different metals are different, the corresponding high-temperature pressure fusion temperatures are different. When the metal outer pipe reaches the phase transition temperature of austenite transformation, the molecular activity degree of metal is increased, the interface reaction of the bimetal interface is easier to occur, and the high-temperature pressure fusion between the bimetal layers is realized under the conditions of the same temperature and the same pressure.
As shown in fig. 1 and 2, in an embodiment, the intermediate frequency induction heating coil sequentially disposed between the roller beds specifically includes:
after passing through a plurality of preheating coils, the expanding agent is heated to decompose gas;
under the condition of the same temperature and the same gas expansion pressure, the high-temperature pressure fusion temperature is reached when the induction coil is fused by high-temperature pressure;
the expansion force of the metal inner pipe and decomposed gas is relied on to force the metal inner pipe to expand and generate plastic deformation, the metal inner pipe is tightly attached to the inner wall of the metal outer pipe and generates interface reaction, and simultaneously, the metal interface of the metal inner pipe and the metal outer pipe is fused under the action of medium-frequency induced current skin effect. The linear expansion coefficient of the stainless steel is larger than that of the carbon steel, when the stainless steel inner pipe and the carbon steel outer pipe are heated to the same temperature, the stainless steel inner pipe can form pressure on the inner wall of the carbon steel outer pipe due to relatively large expansion amount, and similarly, the carbon steel outer pipe can form pressure on the outer wall of the stainless steel inner pipe due to relatively small expansion amount.
In one aspect of this embodiment, the inner wall of the metal outer tube is grit blasted. After the inner wall of the carbon steel outer pipe is subjected to sand blasting treatment, the inner wall is provided with texture bulges, the bulges are wound and melted under the action of induced current skin effect, and the uniformly distributed local fusion is formed between the bimetallic layers under the action of high temperature and high pressure, which is similar to welding fusion.
It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.
Claims (2)
1. A method of forming a metal composite pipe, the method comprising:
a plurality of medium-frequency induction heating coils are sequentially and evenly arranged between the rotating straight roller ways; the front multiple intermediate frequency induction heating coils are preheating coils, and the last stage of intermediate frequency induction heating coil is a high-temperature pressure fusion induction coil;
placing the metal composite pipe with the expansion agent packaged inside on a roller way to rotate and move forwards;
sequentially passing through a medium-frequency induction heating coil arranged between the roller ways;
fusing the metal interface pressure of the inner metal pipe and the outer metal pipe;
the induction temperature of the front plurality of preheating coils is set to be the temperature at which the expanding agent is completely decomposed; setting the induction temperature of the last-stage high-temperature pressure fusion induction coil as a high-temperature pressure fusion temperature, wherein the high-temperature pressure fusion temperature is the phase transition temperature of the metal outer pipe;
the intermediate frequency induction heating coil that loops through and sets up between the roll table specifically includes:
after passing through a plurality of preheating coils, the expanding agent is heated to decompose gas;
under the conditions of the same temperature and the same gas expansion pressure, the high-temperature pressure fusion temperature is reached when the induction coil is fused through high-temperature pressure;
the metal inner pipe is forced to expand to generate plastic deformation by means of the expansion force of the metal inner pipe and decomposed gas, the metal inner pipe is tightly attached to the inner wall of the metal outer pipe and generates interface reaction, meanwhile, the metal interface pressure of the metal inner pipe and the metal outer pipe is fused under the action of the medium-frequency induced current skin effect, and the metal inner pipe is placed in the metal outer pipe and is subjected to sand blasting treatment on the inner wall of the metal outer pipe before being placed inside the metal outer pipe.
2. The method of claim 1, wherein the sum of the pitches of the plurality of induction heating coils is equal to the length of the composite tube.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110688656.7A CN113333598B (en) | 2021-06-22 | 2021-06-22 | Processing method of metal composite pipe |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110688656.7A CN113333598B (en) | 2021-06-22 | 2021-06-22 | Processing method of metal composite pipe |
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| CN113333598A CN113333598A (en) | 2021-09-03 |
| CN113333598B true CN113333598B (en) | 2023-02-14 |
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|---|---|---|---|---|
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2021
- 2021-06-22 CN CN202110688656.7A patent/CN113333598B/en active Active
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| CN113333598A (en) | 2021-09-03 |
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Denomination of invention: A processing method for metal composite pipes Effective date of registration: 20231030 Granted publication date: 20230214 Pledgee: Qilu Bank Co.,Ltd. Dongying Dongying District Branch Pledgor: SHANDONG SHENGLI CHANGLONG PIPELINE TECHNOLOGY CO.,LTD. Registration number: Y2023980063359 |
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