Blade part machining method capable of protecting machine tool and cutter

Abstract

The invention discloses a blade type part machining method capable of protecting a machine tool and a cutter, and relates to the field of blade type part machining.The blade type part machining method mainly comprises the following steps that a blade is cut for the first time, characteristic parameters in the cutting process are obtained, and the characteristic parameters are initial parameters; determining rotation angle ranges corresponding to different cutting volumes of the blade according to the initial parameters; determining a program segment for machining the corresponding rotation angle range in the machine tool according to each rotation angle range; cutting parameters in the program segment are adjusted, so that the characteristic parameters in the cutting process are changed to be within the set proportion range of the average value of the initial parameters; cutting the blade for multiple times by the machine tool; and the steps are repeated, and machining of the blade is completed. When the method is used for machining the blade, cutting force fluctuation, cutting vibration and impact generated during circulating non-uniform cutting in the machining process can be effectively reduced, and the purpose of protecting a machine tool and a cutter is achieved.

Description

Technical Field

[0001] The invention relates to the field of blade part processing, in particular to a blade part processing method capable of protecting a machine tool and a cutting tool. Background Art

[0002] As important components of high-end CNC machine tools, the working stability and positioning accuracy of the feed system and spindle system are crucial to ensuring the processing quality and efficiency of machine tool parts. The mechanical transmission structure of the CNC machine tool feed system is mainly composed of servo motors, couplings, ball screw pairs, rolling bearings and guide rail pairs. The spindle of a CNC machine tool is mainly composed of a spindle box, a spindle motor, bearings, seals, etc. The spindle of a CNC machine tool is one of the core components of a CNC machine tool, which directly affects the performance and processing accuracy of the CNC machine tool. Rolling bearings mainly support the spindle, bear radial and axial forces, or support the operation of ball screw pairs. The most common type of failure is wear failure, which will increase the gap between the bearing rolling element and the inner and outer ring raceways, reduce the accuracy of the bearing operation, and cause the spindle system rotation accuracy to decrease, and the feed system movement or rotation accuracy to decrease. The ball screw pair will be under high load and high speed working conditions for a long time, and is prone to wear and bending deformation, affecting the stability of the feed movement, and may also cause motor overload and creep. The coupling may be cracked or the screws loosened, causing the transmission to be out of sync, or even interference with the workbench. When the guide rail pair is not lubricated enough or the load is too large, it may cause damage to the rail surface, resulting in poor movement of the slider and creeping.

[0003] In the process of machining blade parts made of difficult-to-machine materials such as high-strength stainless steel, titanium alloy, and high-temperature alloy, due to the characteristics of high cutting force, high cutting temperature, and severe tool wear during the cutting of difficult-to-machine materials, and the different volumes of cutting materials during the 360-degree rotation of the blade, large fluctuations in cutting force, large impacts, and large cutting vibrations are generated during the cutting process. Uneven cyclic cutting will aggravate the wear of the spindle and feed system bearings, the wear and bending of the ball screw pair, and thus cause problems such as reduced rotation accuracy of the spindle system, reduced movement or rotation accuracy of the feed system, and even cause the premature scrapping of key components such as bearings, ball screw pairs, and guide rails. At the same time, uneven cyclic cutting will aggravate tool wear and breakage, reduce tool life, increase tool use costs, reduce production efficiency, and increase tool replacement time.

[0004] Therefore, a new processing method for blade parts is needed. Summary of the invention

[0005] The object of the present invention is to provide a machining method for blade-like parts that can protect machine tools and cutting tools. When machining blades, it can effectively reduce the cutting force fluctuations, cutting vibrations and impacts generated during uneven cyclic cutting in the machining process, achieving the purpose of protecting key components of machine tools, extending the service life of machine tools, reducing tool wear and breakage, increasing the service life of tools, reducing tool usage costs, improving production efficiency, and reducing tool change time.

[0006] The technical solution adopted by the present invention is as follows: A machining method for blade-like parts that can protect machine tools and cutting tools, comprising the following steps: S1: Select a suitable machining machine tool and cutting parameters according to the shape, size and precision requirements of the blade, and clamp the blade on the rotating shaft of the machining machine tool; for blades with complex shapes and high precision requirements, such as aero-engine blades, gas turbine blades, etc., a five-axis machining machine tool can be selected; for occasions with high requirements for machining efficiency, such as mass-produced blades, a 4+2-axis machine tool can be selected; and for titanium alloy superalloy blades, because titanium alloys and superalloys have characteristics such as high strength, low thermal conductivity, and work hardening, which make it easy to generate large cutting forces and high cutting temperatures during machining, thereby affecting machining efficiency and surface quality, so the parameters for rough machining can be: cutting speed 50-150 m / min, feed rate 0.1-0.2 mm / tooth, cutting depth 1-3 mm; the parameters for finish machining can be: cutting speed 80-200 m / min, feed rate 0.15 mm / tooth, cutting depth 0.5 mm; of course, for other materials, superalloys, the cutting speed can be optimized to 20-50 m / min.

[0007] S2: Start the rotating shaft, and the rotating shaft drives the blade to rotate at least one week. At the same time, the cutting tool cuts the blade, and characteristic parameters of the cutting process are obtained. These characteristic parameters are the initial parameters; preferably one week, of course, it can also rotate more weeks, as long as the characteristic parameters of cutting within the 360° range on the blade can be completely obtained.

[0008] S3: Determine the rotation angle range corresponding to different cutting volumes of the blade according to the initial parameters; within the same or similar cutting volume range, the angle rotated by the rotating shaft is the rotation angle range; specifically, the initial parameter is numerically at the peak position, and the corresponding cutting volume is larger; the initial parameter is numerically at the trough position, and the corresponding cutting volume is smaller or there is uncut material.

[0009] S4: Determine the program segments in the machine tool for machining the corresponding rotation angle ranges according to each rotation angle range.

[0010] S5: Adjust the cutting parameters in the program segment to change the characteristic parameters of the cutting process to within the set proportion range of the average value of the initial parameters. Specifically, for the range of rotational angles at the peak, the characteristic parameters when cutting the material of the blade within this range of rotational angles can be reduced by decreasing the cutting parameter values, such as the rotational speed of the spindle, the feed rate of the tool, the cutting width, the cutting depth, and the rotational speed of the rotating axis. For the range of rotational angles at the trough, the characteristic parameters when cutting the material of the blade within this range of rotational angles can be increased by increasing the cutting parameter values, such as the rotational speed of the spindle, the feed rate of the tool, the cutting width, the cutting depth, and the rotational speed of the rotating axis. Thereby, the fluctuations of the cutting force and the changes in the degree of cutting vibration and impact generated during the uneven cutting of the blade within 360° are weakened, and further, the purpose of protecting the key components of the machine tool, extending the service life of the machine tool, reducing the wear and breakage of the tool, increasing the service life of the tool, reducing the tool usage cost, improving the production efficiency, and reducing the tool replacement time is achieved.

[0011] S6: The machine tool performs multiple cuts on the blade, and the cutting parameters for each cut are the cutting parameters in step S5. Its main purpose is to cut the blade material in some ranges of rotational angles with increased or decreased cutting parameters.

[0012] S7: After completing step S6, the range of rotational angles corresponding to different cutting volumes of the blade will change. Taking the characteristic parameters obtained from the last cut in step S6 as the initial parameters, repeat steps S3 - S6 to complete the machining of the blade.

[0013] Furthermore, in step S1, the processing machine tool is a machine tool with a spindle, that is, preferably a five-axis machining center, which can complete the multi-sided machining of the blade at one time, reduce the number of clamping times, improve the processing efficiency, and at the same time can achieve the machining of the blade with high precision, and can ensure the profile accuracy and dimensional accuracy of the blade.

[0014] Furthermore, in step S2, the characteristic parameters include one or more of cutting force, torque, bending moment, and spindle current.

[0015] Furthermore, in step S2, sensors are installed on the tool shank and the rotating axis to obtain the cutting force, torque, and bending moment in the characteristic parameters, such as strain gauges; or a tool shank or rotating axis with the function of obtaining the cutting force, torque, and bending moment in the characteristic parameters is adopted.

[0016] Furthermore, in step S2, the processing machine tool directly obtains the current driving the spindle rotation in the control system as the spindle current.

[0017] It should be noted that, no matter which method is used to obtain the characteristic parameters, it is known to those skilled in the art. At the same time, the method of obtaining the characteristic parameters is not the focus of the disclosed solution of the present invention. Therefore, no detailed description will be given in this specification.

[0018] Further, in step S5, the cutting parameters include any one or more of the rotational speed of the main shaft, the feed rate of the tool, the cutting width, the cutting depth, and the rotational speed of the rotating shaft.

[0019] Further, in step S5, the set ratio range is 90% - 110%, that is, within the range of ±10% of the average value; we found that changing the characteristic parameters to within the range of ±10% of the average value of the initial parameters can achieve an effective balance in terms of efficiency and the protection of the tool and the machine tool; specifically, if the characteristic parameters are changed to be lower than this range, such as only reaching 50% of the average value, then there is a lack of efficiency; if the characteristic parameters are changed to be higher than this range, such as reaching 150% of the average value, the characteristic parameter value is large, and there is a lack of protection for the tool and the machine tool.

[0020] Further, in step S6, the number of cutting times does not exceed 10 times.

[0021] Further, in step S6, the number of cutting times is uncertain. When cutting, the characteristic parameters obtained are used to determine the range of rotation angles corresponding to different cutting volumes of the blade. When the change amount of the current rotation angle range compared with the rotation range determined by the initial parameters exceeds 5%, the machine tool completes multiple cuts on the blade.

[0022] In summary, due to the adoption of the above technical solutions, the beneficial effects of the present invention are as follows: The present invention obtains the range of rotation angles corresponding to different cutting volumes of the blade, adjusts the cutting parameters according to the range of rotation angles, so that during the subsequent cutting process, the characteristic parameters during cutting within the corresponding range of rotation angles are changed to within the set ratio range of the average value of the initial parameters, thereby effectively reducing the cutting force fluctuation, cutting vibration and impact degree generated during uneven cyclic cutting in the machining process, achieving the purpose of reducing tool wear and breakage, increasing the tool service life, reducing the tool usage cost, improving the production efficiency, reducing the tool change time, and reducing the damage degree to key components such as bearings, ball screw pairs, and guide rails on the machine tool, and at the same time having the effect of protecting the machine tool and extending its service life. Specific embodiments

[0023] In the description of this specification, it should be noted that if terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are used to indicate the orientation or positional relationship, it is based on the shown orientation or positional relationship, or the orientation or positional relationship in which the product of this specification is usually placed during use. This is only for the convenience of describing this specification and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to this specification.

[0024] In addition, in the description of this specification, if terms such as "horizontal" and "vertical" are used, it does not mean that the components are required to be absolutely horizontal or hanging vertically, but they can be slightly inclined. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and it does not mean that this structure must be completely horizontal, but it can be slightly inclined.

[0025] In the description of this specification, it should also be noted that unless otherwise clearly specified and limited, if terms such as "set", "installed", "connected", "linked" are used, they should be understood in a broad sense. For example, the connection can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components.

[0026] Embodiment A method for machining blade-like parts that can protect machine tools and cutting tools. Taking the machining of titanium alloy blade-like parts as an example, it includes the following steps: S1: Select a suitable machining machine tool and cutting parameters according to the blade, and clamp the blade on the rotating shaft of the machining machine tool; the machining machine tool is a five-axis machining machine tool with a main shaft, the cutting tool is a carbide end mill with a diameter of 25 mm, and the cutting parameters are: rotational speed 380 r / min - 800 r / min, feed 450 mm / min - 720 mm / min, cutting width 8 mm - 12.5 mm, cutting depth 0.8 mm - 1.5 mm.

[0027] S2: Start the rotating shaft, and the rotating shaft drives the blade to rotate at least one week. At the same time, the cutting tool cuts the blade with the cutting parameters in step S1, and obtain the characteristic parameters of the cutting process, and this characteristic parameter is the initial parameter; The characteristic parameters include one or more of cutting force, torque, bending moment, and spindle current; Install sensors on the tool shank and the rotating shaft to obtain the cutting force, torque, and bending moment in the characteristic parameters; or use a tool shank or a rotating shaft with the function of obtaining the cutting force, torque, and bending moment in the characteristic parameters; Directly obtain the current that drives the main shaft to rotate in the control system of the machining machine tool as the spindle current; In this embodiment, the characteristic parameter is selected as the bending moment, which is obtained by a wireless force-measuring tool shank. The obtained bending moment has a peak value of 42 Nm, a trough value of -14 Nm, and an average value of 28 Nm.

[0028] S3: Determine the range of rotation angles corresponding to different cutting volumes of the blade according to the initial parameters. Of course, when the blade rotates one week, there are multiple ranges of rotation angles within its 360°. The cutting volume corresponding to each range of rotation angles is different, and the size of the range is reflected according to the specific value of the characteristic parameter. For example, a difference in numerical values within ±10% can be considered as the same cutting volume, that is, when the rotating shaft drives the blade to rotate and the tool cuts the same cutting volume, the angle rotated by the rotating shaft is the range of rotation angles. Specifically, when the rotating shaft drives the blade to rotate, if the characteristic parameter generated during the tool cutting the blade is between 20.68 Nm and 22.74 Nm, it can be considered that the cutting volume cut by the tool is the same cutting volume, and the corresponding rotating shaft angle is 30° - 40°, then the range of rotation angles is 30° - 40°; another example is that when the tool cuts the blade and the characteristic parameter generated is between 35.43 Nm and 42.00 Nm, it can be considered that the cutting volume cut by the tool is the same cutting volume, and the corresponding rotating shaft angle is 225° - 250°, then the range of rotation angles is 225° - 250°.

[0029] S4: Determine the program segments in the machine tool that process the corresponding ranges of rotation angles according to each range of rotation angles, such as finding the program segments where the rotating shaft rotates by 30° - 40° and 225° - 250°.

[0030] S5: Adjust the cutting parameters in the program segment to change the characteristic parameter during the cutting process to within the set proportion range of the average value of the initial parameters. The set proportion range is 90% - 110%; the cutting parameters to be adjusted include any one or more of the rotational speed of the main shaft, the feed rate of the tool, the cutting width, the cutting depth, and the rotational speed of the rotating shaft. In this embodiment, taking the average value of the characteristic parameter as 28 Nm as an example, the bending moment values corresponding to the set proportion range are 25.2 Nm - 30.8 Nm; then the rotational speed of the main shaft, the feed rate of the tool, the cutting width, the cutting depth, and the rotational speed of the rotating shaft can be reduced so that the bending moment when cutting the material of the blade in this range of rotation angles is within the range of 25.2 Nm - 30.8 Nm; further, the rotational speed of the main shaft can be adjusted by adjusting the power of the main shaft motor, etc., and the rotational speed of the rotating shaft can be adjusted by adjusting the power of the rotating shaft motor.

[0031] S6: The machine tool performs multiple cuts on the blade, and the cutting parameters for each cut are the cutting parameters in step S5. The number of cutting times generally does not exceed 20 times; or as the machining progresses, the position of the rotation angle range on the blade changes, that is, the number of cutting times is uncertain. The characteristic parameters obtained during cutting are used to determine the rotation angle range corresponding to different cutting volumes of the blade. When the change amount of the current rotation angle range compared to the rotation range determined by the initial parameters exceeds 5%, the machine tool completes multiple cuts on the blade.

[0032] S7: Take the characteristic parameters obtained from the last cut in step S6 as the initial parameters, and repeat steps S3 - S6 to complete the machining of the blade.

[0033] It is found through practice that compared with the traditional machining method, when using the method disclosed in this embodiment until the tool is damaged, for the same type of tool, the number of blades machined by the method disclosed in this embodiment has increased by 15%, and the time taken to complete the machining of the blade is only slightly lower than that of the traditional machining method, with an average time-consuming of 104% of the time taken by the traditional machining method to complete the machining of the blade. Thus, it can be known that by obtaining the rotation angle range corresponding to different cutting volumes of the blade and adjusting the cutting parameters according to the rotation angle range, during the subsequent cutting process, the characteristic parameters during cutting within the corresponding rotation angle range are changed to within the set ratio range of the average value of the initial parameters, thereby effectively reducing the cutting force fluctuation, cutting vibration and impact degree generated during uneven cyclic cutting in the machining process, achieving the purpose of reducing tool wear and breakage, increasing tool service life, reducing tool usage cost, improving production efficiency, reducing tool replacement time, and reducing the damage degree to key components such as bearings, ball screw pairs, and guide rails on the machine tool, while having the effect of protecting the machine tool and extending its service life.

[0034] The present invention is not limited to the foregoing specific embodiments. The present invention extends to any new feature or any new combination disclosed in this specification, as well as any new method or process step or any new combination disclosed.

Claims

1. A blade parts processing method capable of protecting machine tools and cutting tools, characterized in that: The following steps are involved: S1: Select a suitable processing machine tool and cutting parameters according to the blade, and clamp the blade on the rotating axis of the processing machine tool; S2: Start the rotating shaft, and the rotating shaft rotates the blade for at least one circle. At the same time, the tool cuts the blade and obtains characteristic parameters of the cutting process, which are initial parameters. S3: Determine the rotation angle range corresponding to different cutting volumes of the blade according to the initial parameters; S4: Determine the program segment for processing the corresponding rotation angle range in the machine tool according to each rotation angle range; S5: Adjust the cutting parameters in the program segment so that the characteristic parameters of the cutting process are changed to within a set ratio range of the average value of the initial parameters; S6: The machine tool performs multiple cutting on the blade, and the cutting parameters of each cutting are the cutting parameters in step S5; S7: Using the characteristic parameters obtained by the last cutting in step S6 as initial parameters, repeat steps S3-S6 to complete the processing of the blade.

2. The blade parts processing method capable of protecting machine tools and cutting tools according to claim 1 is characterized in that: In step S1 , the processing machine tool is a processing machine tool having a main spindle.

3. The blade parts processing method capable of protecting machine tools and cutting tools according to claim 2 is characterized in that: In step S2, the characteristic parameters include one or more of cutting force, torque, bending moment, and spindle current.

4. The blade parts processing method capable of protecting machine tools and cutting tools according to claim 3 is characterized in that: In step S2, sensors are installed on the tool handle and rotating shaft of the tool to obtain the cutting force, torque and bending moment among the characteristic parameters; or a tool handle and rotating shaft with the function of obtaining the cutting force, torque and bending moment among the characteristic parameters are used.

5. The blade parts processing method capable of protecting machine tools and cutting tools according to claim 3 is characterized in that: In step S2 , the processing machine tool directly obtains the current driving the spindle to rotate in the control system as the spindle current.

6. The blade parts processing method capable of protecting machine tools and cutting tools according to claim 2 is characterized in that: In step S5 , the cutting parameters include any one or more of the spindle speed, the tool feed speed, the cutting width, the cutting depth and the rotation speed of the rotary axis.

7. The blade parts processing method capable of protecting machine tools and cutting tools according to claim 2 is characterized in that: In step S5, the set ratio range is 90%-110%.

8. The blade parts processing method capable of protecting machine tools and cutting tools according to claim 2 is characterized in that: In step S6, the number of cutting times does not exceed 10 times.

9. The blade parts processing method capable of protecting machine tools and cutting tools according to claim 2, characterized in that: In step S6, the number of cutting times is uncertain, and the characteristic parameters obtained during cutting are used to determine the rotation angle range corresponding to different cutting volumes of the blade. If the current rotation angle range changes by more than 5% compared to the rotation range determined by the initial parameters, the machine tool has completed multiple cutting of the blade.