CN114876603A - Manufacturing method of high-speed high-power internal combustion engine camshaft - Google Patents
Manufacturing method of high-speed high-power internal combustion engine camshaft Download PDFInfo
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- CN114876603A CN114876603A CN202210457453.1A CN202210457453A CN114876603A CN 114876603 A CN114876603 A CN 114876603A CN 202210457453 A CN202210457453 A CN 202210457453A CN 114876603 A CN114876603 A CN 114876603A
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- grinding
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- camshaft
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
- F01L1/02—Valve drive
- F01L1/04—Valve drive by means of cams, camshafts, cam discs, eccentrics or the like
- F01L1/047—Camshafts
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K26/00—Working by laser beam, e.g. welding, cutting or boring
- B23K26/352—Working by laser beam, e.g. welding, cutting or boring for surface treatment
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
- B24B1/00—Processes of grinding or polishing; Use of auxiliary equipment in connection with such processes
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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
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C24/00—Coating starting from inorganic powder
- C23C24/08—Coating starting from inorganic powder by application of heat or pressure and heat
- C23C24/10—Coating starting from inorganic powder by application of heat or pressure and heat with intermediate formation of a liquid phase in the layer
- C23C24/103—Coating with metallic material, i.e. metals or metal alloys, optionally comprising hard particles, e.g. oxides, carbides or nitrides
- C23C24/106—Coating with metal alloys or metal elements only
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- 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 discloses a manufacturing method of a high-speed high-power internal combustion engine camshaft, which comprises the following steps: preprocessing the quenched and tempered blank, and reserving laser cladding processing thickness sizes for the shaft diameter and the cam part; uniformly cladding a metal layer as a transition layer at the shaft diameter and the cam of the preprocessed workpiece by adopting a laser cladding method; grinding the transition layer cladded on the workpiece to ensure the uniformity of the transition layer, and inspecting; if the transition layer is qualified, adopting a laser cladding method to homogenize the metal layer as a functional layer; grinding the functional layer to remove redundant processing allowance; the surface of the invention is manufactured by laser cladding, and the surface is strengthened by laser, so that the wear resistance and corrosion resistance are better; the manufacturing risk is reduced, the subsequent heat treatment links in the original manufacturing method are reduced, and the preparation period is further shortened.
Description
Technical Field
The invention belongs to the technical field of internal combustion engines, and particularly relates to a manufacturing method of a high-speed high-power internal combustion engine camshaft.
Background
The camshaft is one of the important parts of the oil-spraying and gas-distributing transmission system of the internal combustion engine and is directly related to the reliability of the operation of the internal combustion engine. The total length of the camshaft of the high-speed high-power internal combustion engine can reach 1400mm, and belongs to slender shaft parts. In the existing high-speed high-power internal combustion engine camshaft processing technical scheme, a blank usually adopts alloy structural steel or rolling bearing steel, and the core part strength and the working surface wear resistance are respectively ensured through quenching and tempering, induction quenching or carburizing quenching; the surface strengthening mode of induction quenching and carburizing quenching is inconvenient for controlling the thickness and the uniformity of a strengthening layer, and the fatigue of the surface of a cam is easy to cause early wear and microcrack in a working environment with a complex stress state, so that the surface of the cam is ineffective, and the internal combustion engine cannot work normally; meanwhile, by adopting the strengthening mode, the stress (thermal stress and phase change stress) is changed greatly in the strengthening process, and cracks are easy to generate to cause the rejection of workpieces.
Disclosure of Invention
In order to overcome the defects in the background technology, the invention provides a manufacturing method of a high-speed high-power internal combustion engine camshaft, which aims to pre-process part structures including the opening size and the cam profile through machining. And then, printing a wear-resistant layer material by laser cladding, and finally performing surface strengthening by adopting laser to ensure the strength of the core part of the part and the surface wear resistance.
In order to achieve the purpose, the invention provides the following technical scheme:
a manufacturing method of a high-speed high-power internal combustion engine camshaft comprises the following steps:
s1, quenching and tempering the blank to obtain good matching between strength and toughness;
s2, preprocessing the quenched and tempered blank, and reserving laser cladding processing thickness sizes at the shaft diameter and the cam part;
s3, uniformly cladding a metal layer as a transition layer at the position of the shaft diameter and the cam of the workpiece after being preprocessed by adopting a laser cladding method so as to ensure that the functional layer and the matrix for subsequent cladding have good bonding performance;
s4, grinding the transition layer cladded on the workpiece to ensure the uniformity of the transition layer, and carrying out ultrasonic inspection, coloring inspection, hardness inspection and size inspection;
s5, if the transition layer is qualified, adopting a laser cladding method to homogenize the metal layer as a functional layer; if the transition layer is not qualified, repeating the step S4 until the transition layer is qualified;
s6, grinding the functional layer to remove excessive machining allowance;
s7, performing aging treatment to remove the internal stress of the workpiece;
s8, measuring the jumping quantity of the shaft neck and the cam base circle, and grinding in one step if the shaft neck and the cam base circle are detected to be qualified; if the detection is unqualified, performing a correction procedure; the correction procedure is that a press is used for applying pressure at a high point by taking center holes at two ends of a camshaft as a reference for correction, and if the correction value is larger than 0.5mm, the steps S7 to S8 are repeated until the detection of the jumping amount is qualified;
s9, grinding the functional layer, and carrying out ultrasonic inspection, coloring inspection, hardness inspection and size inspection on the finished functional layer to ensure the quality of the functional layer;
s10, processing and checking the qualified workpiece in the step S9, and performing surface strengthening on the excircle of the shaft neck and the contour of the cam by adopting laser to improve the strength;
s11, polishing to improve and ensure the contour surface quality of the camshaft;
and S12, final inspection and oil seal storage.
Wherein the thickness of the laser cladding metal layer obtained in the step S3 is 3-3.35 mm; the thickness of the ground transition layer obtained in the step S4 is 0.5-1 mm; the thickness of the laser cladding functional layer obtained in the step S5 is 3-3.5 mm.
As a further optimization, after step S5 and before step S6, the method further includes: and 501, aging treatment is carried out to eliminate the internal stress of the workpiece.
Wherein the grinding process of step S9 includes double feed grinding, wherein the second grinding is non-feed grinding.
As a further optimization, after step S10 and before step S11, the method further includes: s101, performing nondestructive flaw detection on the workpiece obtained in the step S10, and if flaw detection shows that the workpiece is damaged by cracks, performing scrapping treatment; if no crack is found during flaw detection, the subsequent process is carried out, and the workpiece entering the subsequent process is ensured to have no crack.
Compared with the prior art, the invention has the beneficial effects that:
compared with the conventional camshaft processing scheme, the blank is made of high-quality carbon structural steel, and compared with alloy structural steel and rolling bearing steel, the blank is lower in raw material cost; the surface is manufactured by laser cladding, and the surface is reinforced by laser, compared with the conventional reinforcing mode, the wear-resistant layer is more uniform, and the cladding layer is made of nickel-based and cobalt-based materials, so that the wear resistance and corrosion resistance are better; the cam joint is manufactured on the surface of the steel substrate by a laser direct metal deposition method, so that the manufacturing risk is reduced, the subsequent heat treatment links in the original manufacturing method are reduced, and the preparation period is further shortened.
Drawings
FIG. 1 is a schematic flow chart of the method of example 1 of the present invention;
FIG. 2 is a schematic view of the camshaft structure of embodiment 1 of the invention;
fig. 3 is a schematic view of a camshaft cladding structure in embodiment 1 of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention are clearly and completely described below with reference to the drawings of the present invention, and it is obvious that the described embodiments are only a part of the preferred embodiments of the present invention, and not all embodiments. It should be understood by those skilled in the art that these embodiments are only for explaining the technical principle of the present invention, and are not intended to limit the scope of the present invention. In the description of the present invention, it is to be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships illustrated in the drawings, and are used merely for convenience in describing the present invention and for simplicity in description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and thus, are not to be construed as limiting the present invention. Further, in the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.
Example 1: please refer to fig. 1-3;
the invention provides the following technical scheme: a manufacturing method of a high-speed high-power internal combustion engine camshaft is applied to the camshaft shown in figure 2, and comprises the steps shown in figure 1, and specifically comprises the following steps:
and S1, quenching and tempering the blank to obtain good matching of strength and toughness.
And S2, preprocessing the quenched and tempered blank, wherein the sizes of the shaft diameter and the cam part are smaller than the size of the finished product, and the single side is smaller than the finished product by 3 mm.
And S3, uniformly cladding a metal layer of 3-3.5 mm serving as a transition layer at the shaft diameter and the cam of the preprocessed workpiece by adopting a laser cladding method so as to provide a functional layer and a substrate for subsequent cladding with good bonding performance.
S4, grinding the transition layer cladded on the workpiece to ensure the uniformity of the transition layer, controlling the final thickness of the transition layer to be 0.5-1mm, and carrying out ultrasonic inspection, coloring inspection, hardness inspection and size inspection;
s5, if the transition layer is qualified, uniformly cladding a metal layer of 3-3.5 mm serving as a functional layer by adopting a laser cladding method; if the transition layer is not qualified, repeating the step S4 until the transition layer is qualified;
s501, aging treatment is carried out to eliminate internal stress;
s6, grinding the functional layer to remove excessive machining allowance;
s7, performing aging treatment to remove the internal stress of the workpiece;
s8, measuring the jumping quantity of the shaft neck and the cam base circle, and grinding in one step if the shaft neck and the cam base circle are detected to be qualified; if the detection is unqualified, performing a correction procedure; the correction procedure is that a press is used for applying pressure at a high point by taking center holes at two ends of a camshaft as a reference for correction, and if the correction value is larger than 0.5mm, the steps S7 to S8 are repeated until the detection of the jumping amount is qualified;
s9, grinding the functional layer at a feeding rate of 2 times, wherein the 2 nd grinding is non-feeding grinding, ultrasonic inspection, coloring inspection, hardness inspection and size inspection are carried out after finishing the grinding to ensure the quality of the functional layer, and the final thickness of the functional layer is within the range of 2-2.5 mm;
s10, processing and checking the qualified workpiece in the step S9, and performing surface strengthening on the excircle of the shaft neck and the contour of the cam by adopting laser;
s101, performing nondestructive flaw detection on the workpiece obtained in the step S10, and if flaw detection shows that the workpiece is damaged by cracks, performing scrapping treatment; if no crack is found during flaw detection, the subsequent process is carried out, and the workpiece entering the subsequent process is ensured to have no crack;
s11, polishing to improve and ensure the surface quality of the working journal and the cam profile;
s12, final inspection and oil sealing;
compared with the conventional camshaft processing scheme, the blank is made of high-quality carbon structural steel, and compared with alloy structural steel and rolling bearing steel, the cost of raw materials is lower; the surface is manufactured by laser cladding, and is strengthened by laser, compared with the conventional strengthening mode, the wear-resistant layer is more uniform, and the wear resistance and the corrosion resistance are better; the cam joint is manufactured on the surface of the steel substrate by a laser direct metal deposition method, so that the manufacturing risk is reduced, the subsequent heat treatment links in the original manufacturing method are reduced, and the preparation period is further shortened.
The invention is not described in detail in the prior art; for a person skilled in the art, various technical features of the embodiments described above may be combined arbitrarily, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, however, as long as there is no contradiction between the combinations of the technical features, the combinations should be considered as the scope of the present description. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (5)
1. A manufacturing method of a camshaft of a high-speed high-power internal combustion engine is characterized by comprising the following steps:
s1, quenching and tempering the blank to obtain good matching between strength and toughness;
s2, preprocessing the quenched and tempered blank, and reserving laser cladding processing thickness sizes at the shaft diameter and the cam part;
s3, uniformly cladding a metal layer as a transition layer at the position of the shaft diameter and the cam of the workpiece after being preprocessed by adopting a laser cladding method so as to ensure that the functional layer and the matrix for subsequent cladding have good bonding performance;
s4, grinding the transition layer cladded on the workpiece to ensure the uniformity of the transition layer, and carrying out ultrasonic inspection, coloring inspection, hardness inspection and size inspection;
s5, if the transition layer is qualified, adopting a laser cladding method to homogenize the metal layer as a functional layer; if the transition layer is not qualified, repeating the step S4 until the transition layer is qualified;
s6, grinding the functional layer to remove excessive machining allowance;
s7, performing aging treatment to remove the internal stress of the workpiece;
s8, measuring the jumping amount of the shaft neck, and grinding in one step if the jumping amount is qualified; if the detection is unqualified, performing a correction procedure; the correction procedure is that a press is used for applying pressure at a high point by taking center holes at two ends of a camshaft as a reference for correction, and if the correction value is larger than 0.5mm, the steps S7 to S8 are repeated until the detection of the jumping amount is qualified;
s9, grinding the functional layer, and carrying out ultrasonic inspection, coloring inspection, hardness inspection and size inspection on the finished functional layer to ensure the quality of the functional layer;
s10, processing and checking the qualified workpiece in the step S9, and performing surface strengthening on the excircle of the shaft neck and the contour of the cam by adopting laser to improve the strength;
s11, polishing to improve and ensure the contour surface quality of the camshaft;
and S12, final inspection and oil seal storage.
2. The method for manufacturing a camshaft for a high-speed high-power internal combustion engine according to claim 1, wherein:
the thickness of the laser cladding metal layer obtained in the step S3 is 3-3.35 mm;
the thickness of the ground transition layer obtained in the step S4 is 0.5-1 mm;
the thickness of the laser cladding functional layer obtained in the step S5 is 3-3.5 mm.
3. The method for manufacturing a camshaft of a high-speed high-power internal combustion engine according to claim 2, wherein after step S5 and before step S6, the method further comprises the steps of:
and 501, aging treatment is carried out to eliminate the internal stress of the workpiece.
4. The method for manufacturing a camshaft for a high-speed high-power internal combustion engine according to claim 3, wherein:
the grinding process of step S9 includes double feed grinding, wherein the second grinding is non-feed grinding.
5. The method for manufacturing a camshaft of a high-speed high-power internal combustion engine according to claim 4, wherein after step S10 and before step S11, the method further comprises the following steps:
s101, performing nondestructive flaw detection on the workpiece obtained in the step S10, and if flaw detection shows that the workpiece is damaged by cracks, performing scrapping treatment; if no crack damage is found during flaw detection, the subsequent process is carried out, and the workpieces entering the subsequent process are ensured to have no cracks.
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| CN202210457453.1A CN114876603B (en) | 2022-04-28 | 2022-04-28 | Manufacturing method of high-speed high-power internal combustion engine camshaft |
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| CN202210457453.1A CN114876603B (en) | 2022-04-28 | 2022-04-28 | Manufacturing method of high-speed high-power internal combustion engine camshaft |
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| CN114876603B CN114876603B (en) | 2023-10-10 |
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1411494A (en) * | 1972-08-31 | 1975-10-29 | Schaudt Maschinenbau Gmbh | Method for the grinding of camshafts |
| US4528781A (en) * | 1982-04-29 | 1985-07-16 | Toyoda Koki Kabushiki Kaisha | Method of forming cam by grinding |
| US4621463A (en) * | 1983-10-20 | 1986-11-11 | Toyoda Koki Kabushiki Kaisha | Method of grinding cams on a camshaft |
| JP2000192805A (en) * | 1998-12-25 | 2000-07-11 | Tube Foming Co Ltd | Manufacture of hollow cam shaft and hollow cam shaft |
| CN103498154A (en) * | 2013-09-05 | 2014-01-08 | 江苏翌煜能源科技发展有限公司 | Laser cladding method for surface of automobile engine camshaft |
| DE102013012860A1 (en) * | 2013-08-01 | 2014-04-03 | Daimler Ag | Cam for camshaft, particularly piston internal combustion engine, has external circumference sided cam surface, over which corresponding cam follower is actuated by cam, where cam surface is locally provided to form recesses |
| US20160340762A1 (en) * | 2015-05-20 | 2016-11-24 | Caterpillar Inc. | Cladding Composition and Method for Remanufacturing Components |
| CN112643034A (en) * | 2020-12-16 | 2021-04-13 | 苏州热工研究院有限公司 | Composite additive manufacturing method of large camshaft |
| CN113528793A (en) * | 2021-07-15 | 2021-10-22 | 河北华北柴油机有限责任公司 | Camshaft strengthening treatment process |
-
2022
- 2022-04-28 CN CN202210457453.1A patent/CN114876603B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1411494A (en) * | 1972-08-31 | 1975-10-29 | Schaudt Maschinenbau Gmbh | Method for the grinding of camshafts |
| US4528781A (en) * | 1982-04-29 | 1985-07-16 | Toyoda Koki Kabushiki Kaisha | Method of forming cam by grinding |
| US4621463A (en) * | 1983-10-20 | 1986-11-11 | Toyoda Koki Kabushiki Kaisha | Method of grinding cams on a camshaft |
| JP2000192805A (en) * | 1998-12-25 | 2000-07-11 | Tube Foming Co Ltd | Manufacture of hollow cam shaft and hollow cam shaft |
| DE102013012860A1 (en) * | 2013-08-01 | 2014-04-03 | Daimler Ag | Cam for camshaft, particularly piston internal combustion engine, has external circumference sided cam surface, over which corresponding cam follower is actuated by cam, where cam surface is locally provided to form recesses |
| CN103498154A (en) * | 2013-09-05 | 2014-01-08 | 江苏翌煜能源科技发展有限公司 | Laser cladding method for surface of automobile engine camshaft |
| US20160340762A1 (en) * | 2015-05-20 | 2016-11-24 | Caterpillar Inc. | Cladding Composition and Method for Remanufacturing Components |
| CN112643034A (en) * | 2020-12-16 | 2021-04-13 | 苏州热工研究院有限公司 | Composite additive manufacturing method of large camshaft |
| CN113528793A (en) * | 2021-07-15 | 2021-10-22 | 河北华北柴油机有限责任公司 | Camshaft strengthening treatment process |
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