Machining method for pump cover of variable oil pump

Abstract

The invention discloses a method for machining a pump cover of a variable oil pump, and relates to the technical field of pump cover machining. S2, positioning and clamping are carried out; s3, a rough machining stage; s4, a finish machining stage; s5, special process treatment; (1) heat treatment; (2) surface treatment; s6, checking and testing; and S7, packaging and storing. According to the machining method for the pump cover of the variable oil pump, the hardness and the abrasion resistance of the pump cover of the variable oil pump can be effectively improved through heat treatment by adding a special process treatment procedure, and on the other hand, the corrosion resistance and the attractiveness of the pump cover of the variable oil pump can be effectively enhanced through anodic oxidation treatment; and by adding inspection and test procedures, the size and form and location tolerance of the pump cover of the variable oil pump formed after machining can be accurately measured, meanwhile, the performance indexes such as the sealing performance and the drug resistance of the pump cover of the variable oil pump can be tested, and it is guaranteed that the produced pump cover of the variable oil pump is qualified.

Description

Technical Field

[0001] The invention relates to the technical field of pump cover processing, and in particular to a method for processing a variable oil pump cover. Background Art

[0002] A variable oil pump is a hydraulic pump that can adjust flow and pressure as needed. It adjusts the flow of the pump by changing the inclination angle of the variable head. When the pull rod moves, it pushes the servo piston, thereby changing the pressure oil distribution in the upper and lower chambers of the variable housing, thereby changing the inclination angle of the variable head to adjust the flow. When the inclination angle becomes zero, the variable head will change in the direction of the negative deflection angle to achieve the reversal of the fluid flow.

[0003] The patent with announcement number CN104999220B in the prior art discloses a variable oil pump cover processing method, which includes the following steps: A. Position the pump cover to be processed on a rotatable support plate through a positioning fixture, and first make the support plate horizontal; B. Rough processing the front of the pump cover, including: rough milling the shaft side plane, milling the shaft end face and cover plane, drilling the shaft hole and chamfering the hole; C. Fine processing the front of the pump cover, including: sleeve the shaft side plane and fine boring the shaft hole; D. Rotate the support plate to position the support plate at 15°; E. Drill the inclined oil hole on the inclined surface of the pump cover. The present invention has high processing accuracy and short processing time.

[0004] The method for processing the variable oil pump cover proposed in the above patent technology has the defect that the surface of the variable oil pump cover after processing is not processed, and after processing, the variable oil pump cover cannot be effectively inspected. In view of this. The present invention proposes a method for processing the variable oil pump cover. Summary of the invention

[0005] The invention discloses a method for machining a variable oil pump cover, aiming to solve the technical problems in the background technology.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions: A variable oil pump cover processing method comprises the following steps: S1. Preliminary preparation; (1) Material selection; (2) Drawing review; (3) Preparation of blanks; S2, positioning and clamping; (1) Positioning reference; (2) Clamping design; (3) Preload and check; S3, rough machining stage; (1) Plane milling; (2) Hole processing; S4, finishing stage; (1) Plane finishing milling; (2) Hole finishing; (3) Inclined oil channel processing; S5, special process treatment; (1) Heat treatment; ‌Normalizing treatment‌: Put the pump cover into the ZH800 fully automatic normalizing machine and heat it to 800℃-900℃, keep it warm for a while, and then cool it in the air. Normalizing treatment can increase the wear resistance and hardness of the pump cover‌; Annealing treatment: After normalizing, the pump cover is placed in an RTP150 annealing furnace and heated to 600℃-700℃. After keeping warm for a period of time, it is cooled in the furnace or naturally. Annealing treatment is used to reduce hardness and facilitate subsequent processing and drilling; Quenching treatment: Put the annealed pump cover into a vacuum quenching furnace and heat it to above the critical point, keep it warm and then cool it quickly. Quenching treatment can greatly improve the hardness and strength of the pump cover; Tempering treatment: The pump cover after quenching treatment is placed in a general-purpose sealed box furnace tempering furnace for tempering treatment to eliminate internal stress, adjust hardness, and improve plasticity and toughness. The tempering temperature is usually lower than the quenching temperature. After heat preservation, it is cooled by a method that meets the requirements; (2) Surface treatment; The heat-treated pump cover is subjected to anodizing surface treatment. The specific steps are as follows: ‌Cleaning‌: Remove oil, dust and other impurities on the surface of the pump cover to ensure the surface is clean; Pickling: Soak the pump cover in an acid solution to remove the oxide scale and oxide on the surface and improve the anodizing effect; ‌Anodizing‌: Place the pump cover in an anodizing tank to form an oxide film on the surface of the pump cover through an electrolytic reaction. This process requires controlling the electrolysis time and current density to adjust the thickness of the oxide film.

[0007] Coloring: The anodized pump cover is colored by electrolytic coloring or chemical coloring to make the oxide film present different colors; ‌Sealing‌: Place the colored pump cover into the sealing liquid to seal the micropores in the oxide film, improve the corrosion resistance and sealing performance of the pump cover, and finally clean and dry it‌‌: S6. Inspection and testing The pump cover after surface treatment is inspected and tested. The specific steps are as follows: (1) Dimension inspection: Use tools such as vernier calipers, dry scales, and three-coordinate measuring machines to accurately measure the dimensions of the pump cover to ensure that it meets the design requirements.

[0008] (2) Geometric tolerance inspection: Check the flatness, verticality, parallelism and other geometric tolerances of the pump cover to ensure assembly accuracy.

[0009] (3) Performance test: By simulating actual working conditions, the pump cover’s sealing, pressure resistance and other performance indicators are tested.

[0010] S7, packaging and storage; (1) Cleaning and rust prevention: After processing, clean the pump cover thoroughly to remove processing residues and apply anti-rust oil to prevent rust.

[0011] (2) Packaging: Use appropriate packaging materials, such as foam, cartons or wooden boxes, to ensure that the pump cover is not damaged during transportation and storage.

[0012] In a preferred embodiment, in step S1, When selecting materials, high-strength, corrosion-resistant aluminum alloy or cast iron materials are used to ensure their stability and durability under high temperature and high pressure environments; When reviewing the drawings, carefully review the two-dimensional or three-dimensional drawings of the pump cover according to the design requirements, and clarify the requirements for processing dimensions, tolerances, surface roughness, etc.; When preparing the blank, select the appropriate blank material according to the drawing size, and perform preliminary cutting and deburring.

[0013] In a preferred embodiment, in step S2, When determining the positioning reference, determine the reference of the bottom surface, side surface and specific hole position of the pump cover to ensure the consistency and accuracy of subsequent processing; In the process of clamping, choose the appropriate clamp to ensure that the pump cover is stable and does not shake during processing, while avoiding clamp marks or deformation; During the pre-tightening and calibration process, the fixture is pre-tightened before formal processing, and the position accuracy of the pump cover is checked using a calibration tool.

[0014] In a preferred embodiment, in step S3, In the process of plane milling, a milling machine or machining center is used to rough mill the bottom, top and sides of the pump cover to remove most of the excess and approach the final size; During the hole machining process, the oil inlet hole, oil outlet hole and mounting hole on the pump cover are drilled and bored according to the design requirements. At the same time, attention should be paid to controlling the hole diameter, hole depth and position accuracy.

[0015] In a preferred embodiment, in step S4, When performing plane fine milling, the precision milling process is used to fine mill the key surfaces of the pump cover to ensure that the surface roughness meets the design requirements; During the machining of the inclined oil channel, special tools or a five-axis machining center are required for precise machining to ensure that the oil channel is unobstructed and accurately positioned.

[0016] As can be seen from the above, the variable oil pump cover processing method provided by the present invention has the following technical effects.

[0017] Firstly, the variable oil pump cover processing method proposed in the present invention can gradually perform heat treatment and surface treatment on the processed variable oil pump cover by adding special process treatment procedures. On the one hand, the hardness and wear resistance of the variable oil pump cover can be effectively improved through normalizing, annealing, quenching and tempering treatments in the heat treatment. On the other hand, the corrosion resistance and aesthetics of the variable oil pump cover can be effectively enhanced by anodizing the variable oil pump cover.

[0018] Second: The variable oil pump cover processing method proposed in the present invention, by adding inspection and testing procedures, can accurately measure the size and shape and position tolerances of the variable oil pump cover formed after processing, to ensure that the finished product can perfectly meet the production process requirements, and at the same time can simulate actual working conditions to test the performance indicators such as the sealing and drug resistance of the variable oil pump cover, to ensure that the produced variable oil pump cover is qualified. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A schematic diagram of the steps of a variable oil pump cover processing method proposed by the present invention.

[0020] Figure 2 A schematic diagram of the special process steps of a variable oil pump cover processing method proposed by the present invention.

[0021] Figure 3 A schematic diagram of the inspection and testing steps of a variable oil pump cover processing method proposed in the present invention. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0023] Reference Figures 1 to 3 A variable oil pump cover processing method comprises the following steps: S1. Preliminary preparation; (1) Material selection; Specifically, when selecting materials, high-strength, corrosion-resistant aluminum alloy or cast iron materials are used to ensure their stability and durability under high temperature and high pressure environments.

[0024] (2) Drawing review; Specifically, when reviewing the drawings, carefully review the two-dimensional or three-dimensional drawings of the pump cover according to the design requirements, and clarify the requirements for processing dimensions, tolerances, surface roughness, etc.

[0025] (3) Preparation of blanks; Specifically, when preparing the blank, select the appropriate blank material according to the drawing size, and perform preliminary cutting and deburring.

[0026] S2, positioning and clamping; (1) Positioning reference; Specifically, when determining the positioning reference, the references of the bottom surface, side surface and specific hole positions of the pump cover are determined to ensure the consistency and accuracy of subsequent processing.

[0027] (2) Clamping design; Specifically, in the process of clamping, choose a suitable clamp to ensure that the pump cover is stable and does not shake during processing, while avoiding clamp marks or deformation.

[0028] (3) Preload and check; Specifically, during the pre-tightening and calibration process, the fixture is pre-tightened before formal processing, and a calibration tool is used to check the position accuracy of the pump cover.

[0029] S3, rough machining stage; (1) Plane milling; Specifically, in the process of plane milling, a milling machine or a machining center is used to perform rough milling on the bottom, top and side surfaces of the pump cover to remove most of the excess and approach the final size.

[0030] (2) Hole processing; Specifically, during the hole processing, according to the design requirements, the oil inlet hole, oil outlet hole and mounting hole on the pump cover are drilled and bored, and at the same time, attention needs to be paid to controlling the hole diameter, hole depth and position accuracy.

[0031] S4, finishing stage; (1) Plane finishing milling; Specifically, when performing plane fine milling, a precision milling process is used to perform fine milling on the key surfaces of the pump cover to ensure that the surface roughness meets the design requirements.

[0032] (2) Hole finishing; Specifically, during the machining of the inclined oil channel, special tools or a five-axis machining center are required for precise machining to ensure that the oil channel is unobstructed and accurately positioned.

[0033] (3) Inclined oil channel processing; S5, special process treatment; (1) Heat treatment; ‌Normalizing treatment‌: Put the pump cover into the ZH800 fully automatic normalizing machine and heat it to 800℃-900℃, keep it warm for a while, and then cool it in the air. Normalizing treatment can increase the wear resistance and hardness of the pump cover‌; Annealing treatment: After normalizing, the pump cover is placed in an RTP150 annealing furnace and heated to 600℃-700℃. After keeping warm for a period of time, it is cooled in the furnace or naturally. Annealing treatment is used to reduce hardness and facilitate subsequent processing and drilling; Quenching treatment: Put the annealed pump cover into a vacuum quenching furnace and heat it to above the critical point, keep it warm and then cool it quickly. Quenching treatment can greatly improve the hardness and strength of the pump cover; Tempering treatment: The pump cover after quenching treatment is placed in a general-purpose sealed box furnace tempering furnace for tempering treatment to eliminate internal stress, adjust hardness, and improve plasticity and toughness. The tempering temperature is usually lower than the quenching temperature. After heat preservation, it is cooled by a method that meets the requirements; (2) Surface treatment; The heat-treated pump cover is subjected to anodizing surface treatment. The specific steps are as follows: ‌Cleaning‌: Remove oil, dust and other impurities on the surface of the pump cover to ensure the surface is clean; Pickling: Soak the pump cover in an acid solution to remove the oxide scale and oxide on the surface and improve the anodizing effect; ‌Anodizing‌: Place the pump cover in an anodizing tank to form an oxide film on the surface of the pump cover through an electrolytic reaction. This process requires controlling the electrolysis time and current density to adjust the thickness of the oxide film.

[0034] Coloring: The anodized pump cover is colored by electrolytic coloring or chemical coloring to make the oxide film present different colors; ‌Sealing‌: Place the colored pump cover into the sealing liquid to seal the micropores in the oxide film, improve the corrosion resistance and sealing performance of the pump cover, and finally clean and dry it‌‌: Among them, the variable oil pump cover processing method proposed in the present invention can gradually perform heat treatment and surface treatment on the processed variable oil pump cover by adding special process treatment procedures. On the one hand, the hardness and wear resistance of the variable oil pump cover can be effectively improved through normalizing, annealing, quenching and tempering treatments in the heat treatment. On the other hand, the corrosion resistance and aesthetics of the variable oil pump cover can be effectively enhanced by anodizing the variable oil pump cover.

[0035] S6. Inspection and testing The pump cover after surface treatment is inspected and tested. The specific steps are as follows: (1) Dimension inspection: Use tools such as vernier calipers, dry scales, and three-coordinate measuring machines to accurately measure the dimensions of the pump cover to ensure that it meets the design requirements.

[0036] (2) Geometric tolerance inspection: Check the flatness, verticality, parallelism and other geometric tolerances of the pump cover to ensure assembly accuracy.

[0037] (3) Performance test: By simulating actual working conditions, the pump cover’s sealing, pressure resistance and other performance indicators are tested.

[0038] S7. Packaging and storage (1) Cleaning and rust prevention: After processing, clean the pump cover thoroughly to remove processing residues and apply anti-rust oil to prevent rust.

[0039] (2) Packaging: Use appropriate packaging materials, such as foam, cartons or wooden boxes, to ensure that the pump cover is not damaged during transportation and storage.

[0040] Among them, the variable oil pump cover processing method proposed in the present invention, by adding inspection and testing procedures, can accurately measure the size and shape and position tolerances of the variable oil pump cover formed after processing, to ensure that the finished product can perfectly meet the production process requirements, and at the same time can simulate actual working conditions to test the performance indicators such as the sealing and drug resistance of the variable oil pump cover, to ensure that the produced variable oil pump cover is qualified.

[0041] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. The replacement may be a replacement of a part of the structure, device, method step, or a complete technical solution. Any equivalent replacement or change according to the technical solution and the inventive concept of the present invention shall be covered within the protection scope of the present invention.

Claims

1. A variable oil pump cover processing method, characterized in that: The following steps are involved: S1. Preliminary preparation; (1) Material selection; (2) Drawing review; (3) Preparation of blanks; S2, positioning and clamping; (1) Positioning reference; (2) Clamping design; (3) Preload and check; S3, rough machining stage; (1) Plane milling; (2) Hole processing; S4, finishing stage; (1) Plane finishing milling; (2) Hole finishing; (3) Inclined oil channel processing; S5, special process treatment; (1) Heat treatment; Normalizing treatment: put the pump cover into the ZH800 fully automatic normalizing machine and heat it to 800℃-900℃, keep it warm for a while, and then cool it in the air; Annealing treatment: After normalizing, the pump cover is placed in an RTP150 annealing furnace and heated to 600℃-700℃. After keeping warm for a period of time, it is cooled in the furnace or naturally; Quenching treatment: put the annealed pump cover into a vacuum quenching furnace, heat it to above the critical point, keep it warm and then cool it quickly; Tempering treatment: put the pump cover after quenching treatment into a universal sealed box furnace tempering furnace for tempering treatment; (2) Surface treatment; The heat-treated pump cover is subjected to anodizing surface treatment. The specific steps are as follows: ‌Cleaning‌: Remove oil, dust and other impurities on the surface of the pump cover to ensure the surface is clean; Pickling: Soak the pump cover in an acid solution to remove the oxide scale and oxide on the surface and improve the anodizing effect; ‌Anodizing‌: Place the pump cover in an anodizing tank to form an oxide film on the surface of the pump cover through an electrolytic reaction; Coloring: The anodized pump cover is colored by electrolytic coloring or chemical coloring to make the oxide film present different colors; ‌Sealing‌: Place the colored pump cover into the sealing liquid to seal the micropores in the oxide film, improve the corrosion resistance and sealing performance of the pump cover, and finally clean and dry it‌‌: S6. Inspection and testing; The pump cover after surface treatment is inspected and tested. The specific steps are as follows: (1) Dimension inspection: Use tools such as vernier calipers, dry scales, and three-coordinate measuring instruments to accurately measure the dimensions of the pump cover to ensure that it meets the design requirements; (2) Geometric tolerance inspection: Check the flatness, verticality, parallelism and other geometric tolerances of the pump cover to ensure assembly accuracy; (3) Performance test: By simulating actual working conditions, test the pump cover's sealing, pressure resistance and other performance indicators; S7, packaging and storage; (1) Cleaning and rust prevention: After processing, clean the pump cover thoroughly to remove processing residues and apply anti-rust oil to prevent rust; (2) Packaging: Use appropriate packaging materials, such as foam, cartons or wooden boxes, to ensure that the pump cover is not damaged during transportation and storage.

2. A variable oil pump cover processing method according to claim 1, characterized in that: In step S1, When selecting materials, high-strength, corrosion-resistant aluminum alloy or cast iron materials are used to ensure their stability and durability under high temperature and high pressure environments; When reviewing the drawings, carefully review the two-dimensional or three-dimensional drawings of the pump cover according to the design requirements, and clarify the requirements for processing dimensions, tolerances, surface roughness, etc.; When preparing the blank, select the appropriate blank material according to the drawing size, and perform preliminary cutting and deburring.

3. The variable oil pump cover processing method according to claim 1, characterized in that: In step S2, When determining the positioning reference, determine the reference of the bottom surface, side surface and specific hole position of the pump cover to ensure the consistency and accuracy of subsequent processing; In the process of clamping, choose the appropriate clamp to ensure that the pump cover is stable and does not shake during processing, while avoiding clamp marks or deformation; During the pre-tightening and calibration process, the fixture is pre-tightened before formal processing, and the position accuracy of the pump cover is checked using a calibration tool.

4. The variable oil pump cover processing method according to claim 1, characterized in that: In step S3, In the process of plane milling, a milling machine or machining center is used to rough mill the bottom, top and sides of the pump cover to remove most of the excess and approach the final size; During the hole machining process, the oil inlet hole, oil outlet hole and mounting hole on the pump cover are drilled and bored according to the design requirements. At the same time, attention should be paid to controlling the hole diameter, hole depth and position accuracy.

5. The variable oil pump cover processing method according to claim 1, characterized in that: In step S4, When performing plane fine milling, the precision milling process is used to fine mill the key surfaces of the pump cover to ensure that the surface roughness meets the design requirements; During the machining of the inclined oil channel, special tools or a five-axis machining center are required for precise machining to ensure that the oil channel is unobstructed and accurately positioned.

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