Anti-corrosion oil cooler pipeline structure

Abstract

The invention relates to the technical field of oil cooler pipelines, in particular to an anti-corrosion oil cooler pipeline structure which is characterized in that an oil cooler pipeline is a bent pipe, the lengths of the pipeline bodies at the two ends of the bent pipe are unequal, a port of the long pipeline is in an outwards-protruding arc-shaped closing-up type, and a port of the short pipeline is in an outwards-protruding boss shape and is provided with a pipeline extending section; the structure of the whole pipe wall of the oil cooler pipeline is an aluminum alloy composite material layer, and the aluminum alloy composite material layer takes 3003 aluminum-manganese alloy as a core layer and takes 6-series aluminum alloy as an outer coating layer; at least one 4-series aluminum alloy layer is arranged on the outer surface of the pipeline extension section and the lower surface of the boss, and the material of the 4-series aluminum alloy layer is selected from one of 4004 aluminum alloy, 4047 aluminum alloy, 4343 aluminum alloy and 4032 aluminum alloy; and the following relation needs to be met: the melting point of the core layer is greater than the melting point of the outer coating layer and is greater than or equal to the melting point of the 4-series aluminum alloy layer. According to the structure, the corrosion risk can be resisted, and the liquid leakage and falling risks at the ports can be reduced.

Description

Technical Field

[0001] The invention relates to the technical field of oil cooler pipelines, and in particular to an anti-corrosion oil cooler pipeline structure. Background Art

[0002] As the market demand for ordinary family cars increases, the demand for automotive oil coolers has also increased significantly. At present, the main material for manufacturing automotive oil coolers is aluminum alloy sheets. The oil cooler is mainly used to cool the engine crankcase, clutch, valve assembly, etc. Its main components include oil inlet pipes, water inlet pipes, floors, partitions and fins. Oil cooler pipes are usually made of metal materials, which are corrosion-resistant to a certain extent. However, since the oil cooler pipes are often exposed to oil products during use, which may contain corrosive substances, and are affected by the external environment (such as cooling water, etc.), the oil cooler pipes are at a greater risk of corrosion during long-term use.

[0003] Another commonly used alloy material for pipelines is 3003 aluminum-manganese alloy. Due to its good corrosion resistance, weldability and forming processing characteristics, 3003 aluminum-manganese alloy is widely used in oil tanks, gasoline or lubricating oil pipes, various liquid containers, kitchen utensils, food and chemical product processing and storage devices, tanks and tanks for transporting liquid products, and heat exchangers. The chemical composition of 3003 aluminum-manganese alloy includes Si 0.6%, Cu0.05-0.2%, Mn 1%-1.5%, Fe 0.7%, Zn0%-0.1% and the balance is Al. Because it contains manganese elements, this alloy has good resistance to various environmental conditions such as atmosphere, fresh water, sea water, food, organic acid, gasoline and neutral inorganic salt aqueous solution. The melting point of 3003 aluminum alloy is about 660℃. The tensile strength of this alloy is 140-180MPa, and the conditional yield strength is greater than or equal to 115MPa. It has high plasticity in the annealed state, but low plasticity when cold-hardened. Its mechanical properties are mainly improved by cold working methods. The strength of 3003 aluminum-manganese alloy is relatively low and cannot be strengthened by heat treatment. In addition, its machinability is poor. Although this material has good corrosion resistance when used as the oil cooler pipeline, it also has a high risk of corrosion during long-term use; in addition, due to its high melting point and the need to weld the port at one end of the pipeline to other components, solder is needed to weld the two, which may cause uneven welding density, uneven strength at the weld, and other undesirable factors. During long-term use, it will bring the risk of leakage or even falling off, increasing safety hazards. Summary of the invention

[0004] In order to solve the technical problems of high risk of oil cooler pipeline corrosion and high risk of leakage and falling off at welding points, an anti-corrosion oil cooler pipeline structure is provided. The oil cooler pipeline of the present invention is a three-layer metal composite pipe structure, the core material of the composite pipe is 3003 aluminum-manganese alloy, and a 6-series aluminum alloy coating layer is provided on the outer surface of the core material as an anti-corrosion protective layer. The protective layer can resist the risk of corrosion on the one hand, and reduce the risk of leakage and falling off at the port on the other hand.

[0005] In order to achieve the above objectives, the present invention is implemented through the following technical solutions:

[0006] A corrosion-resistant oil cooler pipeline structure, the oil cooler pipeline is a curved pipe, the lengths of the pipelines at both ends of the curved pipe are unequal, the port of the longer pipeline is in an outwardly convex arc-shaped closing style, and the port of the shorter pipeline is in an outwardly protruding boss shape and has a pipeline extension section; the structure of the overall pipe wall of the oil cooler pipeline is an aluminum alloy composite material layer, the aluminum alloy composite material layer has a 3003 aluminum-manganese alloy as a core layer and a 6 series aluminum alloy as an outer cladding layer;

[0007] Since the 6-series aluminum alloy has a tendency to crack, a layer of 4-series aluminum alloy is provided on at least the outer surface of the pipeline extension section and the lower surface of the boss, and the material of the 4-series aluminum alloy layer is selected from one of 4004 (melting point of about 550-583°C), 4047 (melting point of about 575°C), 4343 (melting point of about 580-600°C), and 4032 (melting point of about 582°C);

[0008] And the following relationship needs to be satisfied: the material melting point of the core layer > the material melting point of the outer covering layer ≥ the material melting point of the 4 series aluminum alloy layer, that is, the melting points of each layer from the core layer to the outer surface decrease in sequence. Therefore, without welding, the 4 series aluminum alloy can make the pipeline extension section of the oil cooler pipeline and the external metal port be able to be melted and bonded at a lower heating temperature, and the bonding strength after cooling is better than that of welding.

[0009] Furthermore, the inner and outer surfaces of the elbow further include a layer of 4 series aluminum alloy, and the arrangement of the 4 series aluminum alloy layer is the same as the arrangement of the 4 series aluminum alloy layer in the pipeline extension section.

[0010] Furthermore, the material of the 4-series aluminum alloy layer is disposed on the surface of the outer coating layer (the surface refers to the inner and outer surfaces of the integral elbow) by spraying or dipping, and the temperature of the spraying or dipping reaches the melting point of the outer coating layer. That is, at the melting point temperature of the outer coating layer material, the 4-series aluminum alloy is in a molten state, and when the elbow is sprayed or dipped, the 6-series aluminum alloy on the inner and outer surfaces of the elbow will be partially melted, so that the 4-series aluminum alloy in a molten state can penetrate into the 6-series aluminum alloy to improve the bonding between the two, and at the same time improve the crack resistance of the 6-series aluminum alloy, so that the anti-corrosion ability is further improved.

[0011] Furthermore, the 6 series aluminum alloy is selected from one of 6061 (melting point of about 582-652°C), 6082 (melting point of about 582-635°C), 6060 (melting point of about 530°C), and 6A02 (melting point of about 575-645°C).

[0012] Furthermore, the total thickness of the pipe wall of the oil cooler pipe is in the range of 1.1-1.5 mm, the thickness of the outer coating layer on both sides accounts for 10±5% of the total thickness of the pipe wall; the thickness of the 4 series aluminum alloy layer is 10±5% of the total thickness of the pipe wall. On the one hand, it has a good fitting effect with the external port, and on the other hand, it has a good bonding strength with the outer coating layer.

[0013] Further, the oil cooler pipeline is a 90° elbow with a curvature radius of 26±1 mm;

[0014] Taking the center line of the oil cooler pipeline as a reference, the ratio of the length of the longer pipeline to the length of the shorter pipeline is in the range of 1.8-2.0:1.

[0015] Furthermore, the outer diameters of the two ports of the elbow are equal to the outer diameter of the oil cooler pipeline, and the outer diameter of the oil cooler pipeline is 14±0.3 mm;

[0016] The outer diameter of the port with an outward convex arc closing style is 1.5±0.3mm larger than the outer diameter of the oil cooler pipeline, and the curvature radius of the convex arc is 1.5±0.5mm; the outer diameter of the port in the shape of an outwardly protruding boss is 5±0.1mm larger than the outer diameter of the oil cooler pipeline, the boss thickness is 2-2.5mm, and the length of the pipeline extension section is 3±0.5mm.

[0017] Beneficial technical effects:

[0018] The oil cooler pipeline of the present invention is a three-layer metal composite pipe structure. The core material of the composite pipe is 3003 aluminum-manganese alloy. The surface of the core material has a 6-series aluminum alloy outer coating layer as an anti-corrosion protective layer. The protective layer can resist the risk of corrosion on the one hand, and reduce the risk of leakage and falling off at the port on the other hand.

[0019] In order to improve the crack resistance of the 6 series aluminum alloy, a layer of 4 series aluminum alloy is arranged on the surface of the outer cladding layer. The melting points of the materials in each layer from the core layer to the outer surface decrease successively. Therefore, without welding, the pipeline extension section can be melted with the external metal port at a lower heating temperature, which is due to the lower melting point of the surface 4 series aluminum alloy. In order to further increase the strength of the melt, the heating temperature can be increased to the melting point of the 6 series aluminum alloy, so that the 4 series aluminum alloy penetrates into the 6 series aluminum alloy to form a composite and melt with the external port to improve the bonding strength and bonding effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the pipeline structure of the oil cooler of the present invention;

[0021] Figure 2 The figure is a schematic diagram of the layer structure of the pipe wall of the oil cooler pipe of the present invention. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present invention will be described clearly and completely below in combination with the embodiments of the present invention and the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. All other embodiments obtained by ordinary technicians in this field without creative work based on the embodiments of the present invention are within the scope of protection of the present invention.

[0023] Unless otherwise specifically stated, the numerical value set forth in these embodiments does not limit the scope of the present invention. The technology and method known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology and method should be considered as a part of the specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values.

[0024] The experimental methods in the following examples without specifying specific conditions are usually measured in accordance with national standards; if there is no corresponding national standard, the method is carried out in accordance with the general standard requirements or general methods.

[0025] Example 1

[0026] An anti-corrosion oil cooler pipeline structure, the structural schematic diagram of which is shown in Figure 1 As shown, the oil cooler pipeline is a 90° elbow with a curvature radius of 26±1mm; the lengths of the pipelines at both ends of the elbow are not equal, the port 21 of the longer pipeline is in an outwardly convex arc-shaped closing style, and the port of the shorter pipeline is in an outwardly protruding boss shape 22 and has a pipeline extension section 23; the structure of the overall pipe wall of the oil cooler pipeline is as shown Figure 2 As shown, it is a three-layer structure, specifically an aluminum alloy composite material layer, wherein the aluminum alloy composite material layer has a 3003 aluminum-manganese alloy as a core layer 11 and a 6061 aluminum alloy as an outer cladding layer 12;

[0027] A layer of 4 series aluminum alloy ( Figure 1 and Figure 2 Not shown), the material of the 4 series aluminum alloy layer is selected from 4047 aluminum alloy;

[0028] Wherein, the total wall thickness of the oil cooler pipeline is T=1.2mm ( Figure 2 As shown in T), the thickness of the two outer coating layers 12 is 120 μm; the thickness of the 4-series aluminum alloy layer on the outer surface of the pipeline extension section 23 is 150 μm;

[0029] Among them, the outer diameters of the two ports of the bent pipe are equal to the outer diameter of the oil cooler pipeline, and the outer diameter of the oil cooler pipeline is 14±0.3mm; taking the intersection of the horizontal center line and the vertical center line of the oil cooler pipeline as the reference, the length of the longer pipeline is 65±2mm (that is, the length of the straight pipe part is about 39mm), and the length of the shorter pipeline is 34mm (including the thickness of the boss, but excluding the length of the pipeline extension section); the outer diameter of the port 21 with an outward convex arc closing style is 1.5±0.3mm larger than the outer diameter of the oil cooler pipeline, and the curvature radius of the convex arc is 1.5±0.5mm; the outer diameter of the port 22 in the shape of a protruding boss is 5±0.1mm larger than the outer diameter of the oil cooler pipeline, the boss thickness is 2.4mm, and the length of the pipeline extension section 23 is 3±0.5mm.

[0030] Example 2

[0031] An anti-corrosion oil cooler pipeline structure, the structural schematic diagram of which is shown in Figure 1 As shown, the oil cooler pipeline is a 90° elbow with a curvature radius of 26±1mm; the lengths of the pipelines at both ends of the elbow are not equal, the port 21 of the longer pipeline is in an outwardly convex arc-shaped closing style, and the port of the shorter pipeline is in an outwardly protruding boss shape 22 and has a pipeline extension section 23; the structure of the overall pipe wall of the oil cooler pipeline is as shown Figure 2 As shown, it is a three-layer structure, specifically an aluminum alloy composite material layer, wherein the aluminum alloy composite material layer has a 3003 aluminum-manganese alloy as a core layer 11 and a 6082 aluminum alloy as an outer cladding layer 12;

[0032] A layer of 4 series aluminum alloy ( Figure 1 and Figure 2 ), the material of the 4 series aluminum alloy layer is selected from 4004 aluminum alloy;

[0033] Wherein, the total wall thickness of the oil cooler pipeline is T=1.2mm ( Figure 2 As shown in T), the thickness of the two outer coating layers 12 is 180 μm; the thickness of the 4-series aluminum alloy layer on the outer surface of the pipeline extension section 23 is 180 μm;

[0034] Among them, the outer diameters of the two ports of the bent pipe are equal to the outer diameter of the oil cooler pipeline, and the outer diameter of the oil cooler pipeline is 14±0.3mm; taking the intersection of the horizontal center line and the vertical center line of the oil cooler pipeline as the reference, the length of the longer pipeline is 65±2mm (that is, the length of the straight pipe part is about 39mm), and the length of the shorter pipeline is 34mm (including the thickness of the boss, but excluding the length of the pipeline extension section); the outer diameter of the port 21 with an outward convex arc closing style is 1.5±0.3mm larger than the outer diameter of the oil cooler pipeline, and the curvature radius of the convex arc is 1.5±0.5mm; the outer diameter of the port 22 in the shape of a protruding boss is 5±0.1mm larger than the outer diameter of the oil cooler pipeline, the boss thickness is 2.4mm, and the length of the pipeline extension section 23 is 3±0.5mm.

[0035] Example 3

[0036] An anti-corrosion oil cooler pipeline structure, the structural schematic diagram of which is shown in Figure 1 As shown, the oil cooler pipeline is a 90° elbow with a curvature radius of 26±1mm; the lengths of the pipelines at both ends of the elbow are not equal, the port 21 of the longer pipeline is in an outwardly convex arc-shaped closing style, and the port of the shorter pipeline is in an outwardly protruding boss shape 22 and has a pipeline extension section 23; the structure of the overall pipe wall of the oil cooler pipeline is as shown Figure 2 As shown, it is a three-layer structure, specifically an aluminum alloy composite material layer, wherein the aluminum alloy composite material layer has a 3003 aluminum-manganese alloy as a core layer 11 and a 6061 aluminum alloy as an outer cladding layer 12;

[0037] A layer of 4 series aluminum alloy is also provided on the inner and outer surfaces of the elbow (including the pipeline extension section 23 and the boss) Figure 1 and Figure 2 Not shown), the material of the 4 series aluminum alloy layer is selected from 4032 aluminum alloy;

[0038] Wherein, the total wall thickness of the oil cooler pipeline is T=1.2mm ( Figure 2 As shown in T), the thickness of the outer coating layer 12 on both sides is 80 μm; the thickness of the 4 series aluminum alloy layer on both sides is 100 μm;

[0039] Among them, the outer diameters of the two ports of the bent pipe are equal to the outer diameter of the oil cooler pipeline, and the outer diameter of the oil cooler pipeline is 14±0.3mm; taking the intersection of the horizontal center line and the vertical center line of the oil cooler pipeline as the reference, the length of the longer pipeline is 65±2mm (that is, the length of the straight pipe part is about 39mm), and the length of the shorter pipeline is 34mm (including the thickness of the boss, but excluding the length of the pipeline extension section); the outer diameter of the port 21 with an outward convex arc closing style is 1.5±0.3mm larger than the outer diameter of the oil cooler pipeline, and the curvature radius of the convex arc is 1.5±0.5mm; the outer diameter of the port 22 in the shape of a protruding boss is 5±0.1mm larger than the outer diameter of the oil cooler pipeline, the boss thickness is 2.4mm, and the length of the pipeline extension section 23 is 3±0.5mm.

[0040] The production process of the above bent pipes follows the usual preparation method of the industry, and the coating thickness is designed according to the upper limit of the coating thickness required by the user. For example, the coating thickness of the product after 1.2mm is 60-180μm, so the intermediate coating rate is 10%. According to the coating rate requirements, the deformation of the coating and substrate during the rolling process is designed according to the law of volume invariance, and the coating slab thickness is calculated according to the following formula: coating rate = coating slab thickness / (substrate slab thickness + 2×coating slab thickness). If the thickness of the substrate slab is 300mm, then the initial coating slab thickness is 37.5mm. Then prepare the slabs of the corresponding materials, use hot rolling to roll the core layer and the coating layer to the corresponding thickness, clean the surface of the material, and then follow the Figure 2 The three-layer structure is stacked in sequence and fixed with a steel belt to prevent movement and impurity adhesion during the subsequent heating process; the three-layer stacked structure is then hot-rolled, cold-rolled, and the two end faces are bent into corresponding shapes to form two ports, and then annealed. The temperature and time of hot rolling and annealing are operated according to the usual settings in the industry, and then the tube is rolled into a tube by a tube forming machine. The tubular intermediate product is further extruded by an extruder to make its opening and seam close, and the seam is welded and finished; at least the outer surface of the pipeline extension section and the lower surface of the boss and the lower surface of the boss are sprayed or dipped with a 4 series aluminum alloy material melt (for example, supersonic flame spraying or direct melt dipping) to a corresponding thickness, or the 4 series aluminum alloy material melt can be sprayed or dipped on the inner and outer surfaces of the integral elbow.

[0041] The present invention has the following configuration in the pipeline extension section: the melting points of the various layers of materials from the core layer to the outer surface are successively reduced, so that the outermost layer of 4-series aluminum alloy can be melted (at least the core layer does not melt) by only a relatively low heating temperature without welding, thereby achieving fusion with the external pipe connection; if the heating temperature further reaches the melting point of the outer coating layer, the 4-series aluminum alloy can penetrate into the 6-series aluminum alloy, thereby improving the crack tendency of the 6-series aluminum alloy, thereby improving the corrosion resistance of the overall elbow, and the fusion strength of the port is better than that of welding; during the corrosion process, the outermost 4-series aluminum alloy layer, the 6-series aluminum alloy outer coating layer and the 3003 aluminum alloy core layer form an electrochemical principle, and the outermost 4-series aluminum alloy layer loses electrons to form corrosion inhibition.

[0042] The composite aluminum alloy layer structure of the tube wall structure of the present invention, 4 series aluminum alloy / 6 series aluminum alloy / 3003 core layer, not only has good mechanical properties and crack resistance, but also has excellent corrosion resistance.

[0043] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An anti-corrosion oil cooler pipeline structure, characterized in that: The oil cooler pipeline is a curved pipe, the lengths of the pipelines at both ends of the curved pipe are unequal, the port (21) of the longer pipeline is in an outwardly convex arc-shaped closing style, and the port (22) of the shorter pipeline is in an outwardly protruding boss shape and has a pipeline extension section (23); the structure of the overall pipe wall of the oil cooler pipeline is an aluminum alloy composite material layer, the aluminum alloy composite material layer has a 3003 aluminum-manganese alloy as a core layer (11) and a 6 series aluminum alloy as an outer cladding layer (12); A layer of 4-series aluminum alloy is provided at least on the outer surface of the pipeline extension section (23) and the lower surface of the boss, and the material of the 4-series aluminum alloy layer is selected from one of 4004, 4047, 4343, and 4032 aluminum alloys; And the following relationship needs to be satisfied: the material melting point of the core layer (11)>the material melting point of the outer cladding layer (12)≥the material melting point of the 4-series aluminum alloy layer.

2. The anti-corrosion oil cooler pipeline structure according to claim 1, characterized in that: The inner and outer surfaces of the bent pipe also include a layer of 4 series aluminum alloy, and the arrangement of the 4 series aluminum alloy layer is the same as the arrangement of the 4 series aluminum alloy layer in the pipeline extension section (23).

3. The anti-corrosion oil cooler pipeline structure according to claim 2, characterized in that: The material of the 4-series aluminum alloy layer is disposed on the surface of the outer coating layer (12) by spraying or dipping, and the temperature of the spraying or dipping reaches the melting point of the material of the outer coating layer (12).

4. The anti-corrosion oil cooler pipeline structure according to any one of claims 1 to 3, characterized in that: The 6 series aluminum alloy is selected from one of 6061, 6082, 6060, and 6A02 aluminum alloys.

5. The anti-corrosion oil cooler pipeline structure according to claim 4, characterized in that: The total wall thickness of the oil cooler pipeline is in the range of 1.1-1.5 mm, and the thickness of the outer coating layers on both sides accounts for 10±5% of the total wall thickness; the thickness of the 4 series aluminum alloy layer is 10±5% of the total wall thickness.

6. The anti-corrosion oil cooler pipeline structure according to claim 5, characterized in that: The oil cooler pipeline is a 90° elbow with a curvature radius of 26±1mm; Taking the center line of the oil cooler pipeline as a reference, the ratio of the length of the longer pipeline to the length of the shorter pipeline is in the range of 1.8-2.0:

1.

7. The anti-corrosion oil cooler pipeline structure according to claim 5, characterized in that: The outer diameters of the two ports of the elbow are equal to the outer diameter of the oil cooler pipeline, and the outer diameter of the oil cooler pipeline is 14±0.3mm; The outer diameter of the port with an outward convex arc closing style is 1.5±0.3mm larger than the outer diameter of the oil cooler pipeline, and the curvature radius of the convex arc is 1.5±0.5mm; the outer diameter of the port in the shape of an outwardly protruding boss is 5±0.1mm larger than the outer diameter of the oil cooler pipeline, the boss thickness is 2-2.5mm, and the length of the pipeline extension section is 3±0.5mm.

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