Method for machining workbench base of vertical lathe

Abstract

The invention relates to a method for machining a workbench base of a vertical lathe. The method comprises the following steps that (1) high rigidity and high stability of a numerical control gantry milling and boring machine structure are determined; (2) a modular combined milling cutter and a modular combined boring cutter which need to be used are determined according to the base of the whole workbench; (3) determining the stability of the cutter in the machining process; (4) designing and simulating the whole machining process by utilizing three-dimensional software; (5) the whole workbench base is fixed to a workbench of the numerical control gantry boring and milling machine, and the levelness and stability of the workbench base are guaranteed; (6) the stability of the workpiece in the machining process is monitored in a fixed meter clamping and pressing mode; (7) selecting a proper cutter and cutting parameters; and (8) after machining is completed, necessary follow-up treatment and precision inspection are carried out. According to the method, the machining efficiency and the machining precision can be effectively improved, the machining cost is effectively reduced, and the method has wide applicability.

Description

Technical Field

[0001] The invention belongs to the technical field of mechanical processing, and in particular relates to a method for processing a vertical lathe worktable base. Background Art

[0002] In the field of mechanical processing, the guide surface and spindle hole of the integral worktable base are traditionally processed by vertical lathes. However, when processing large or complex workpieces, vertical lathes have problems such as low processing efficiency and difficulty in ensuring precision. In order to improve the quality of parts and production efficiency, the original vertical lathe turning method is now adopted to a new method, using a CNC gantry boring and milling machine to mill the guide surface of the integral worktable base, and boring the spindle hole. Production practice shows that the new processing method can greatly improve part quality and production efficiency. Summary of the invention

[0003] The purpose of the present invention is to provide a method for processing a vertical lathe worktable base, using a CNC gantry boring and milling machine instead of a vertical lathe to process the guide surface of the integral worktable base, the end face of the spindle hole and the spindle hole, so as to improve the processing efficiency and ensure the accuracy of the parts.

[0004] In order to achieve the above object, the technical solution of the present invention is as follows.

[0005] A method for machining a vertical lathe worktable base comprises the following steps:

[0006] (1) Based on the analysis of the machine tool structure, it is determined that the high rigidity and high stability of the CNC gantry milling and boring machine structure are utilized to process the guide surface of the integral worktable base, the end face of the spindle hole, and the spindle hole using a one-time clamping and multi-axis linkage processing scheme;

[0007] (2) Determine the modular combination milling cutter and modular combination boring cutter to be used according to the overall workbench base;

[0008] (3) Calculate the diameter of the milling cutter bar and boring cutter bar according to the cutting force of milling and boring, and determine the stability of the tool during the processing;

[0009] (4) Design the processing path of the overall workbench base and use 3D software to simulate the entire processing process;

[0010] (5) Fix the overall worktable base on the worktable of the CNC gantry boring and milling machine to ensure its levelness and stability; complete the processing of the guide surface and the spindle hole in one clamping to avoid positioning errors caused by multiple clamping;

[0011] (6) Use fixed-meter clamping to monitor the stability of the workpiece during processing;

[0012] (7) Select appropriate tools and cutting parameters to improve part processing efficiency;

[0013] (8) After processing is completed, necessary follow-up processing and precision inspection are carried out.

[0014] Furthermore, the modular combination milling cutter in step (2) includes a first automatic tool changing tool taper shank module, a second equal-diameter intermediate module, a C-type indexable face milling cutter module, and an indexable plane compound milling cutter. The second equal-diameter intermediate module is installed at the bottom of the first automatic tool changing tool taper shank module, the C-type indexable face milling cutter module is installed at the bottom of the second equal-diameter intermediate module, and the indexable plane compound milling cutter is installed at the bottom of the C-type indexable face milling cutter module.

[0015] Furthermore, the modular combination boring tool in step (2) includes a second automatic tool changing tool taper shank module, a second equal-diameter intermediate module and a double-edged adjustable indexable boring tool module, and the second automatic tool changing tool taper shank module and the double-edged adjustable indexable boring tool module are respectively installed at the upper and lower positions of the second equal-diameter intermediate module.

[0016] Furthermore, in step (3), the calculation and selection steps of the milling cutter rod diameter are as follows:

[0017] 3a. Calculate the cutting force of spindle hole end face finishing milling:

[0018] Among them, a e is the milling width; f z is the feed per tooth; a p is the milling depth; d 0 is the diameter of the milling cutter; Z is the number of teeth of the Φ315 milling cutter;

[0019] 3b. Calculate the deflection of the milling cutter bar:

[0020] Simplify the force on the tool bar and use the deflection formula and the moment of inertia of the solid cylindrical section

[0021] Calculate, in the above formula, F is the spindle hole end face fine milling cutting force calculated in step 3a, d is the tool rod diameter, 1 is the tool rod length, E is the elastic modulus, and I represents the moment of inertia of the solid cylindrical section.

[0022] Furthermore, in step (3), the calculation and selection steps of the boring bar diameter are as follows:

[0023] 3c. Calculate the radial cutting force of spindle hole fine boring:

[0024]

[0025] in, Take 92; aP is the boring depth; Take 1.0; f is the feed rate; Take 0.75; V c is the cutting speed; Take 0; Take 1, Represents the coefficient.

[0026] 3d. Simplify the force on the tool bar and use the deflection formula and the moment of inertia of the solid cylindrical section

[0027] Calculate, in the above formula, F is the spindle hole end face fine milling cutting force calculated in step 3c, d is the tool rod diameter, 1 is the tool rod length, E is the elastic modulus, and I represents the moment of inertia of the solid cylindrical section.

[0028] Furthermore, the operation method in step (5) is to install the equal height washers and washers on the T-type quick-release bolts under the base of the integral workbench to be processed, and fix them on the flat pressure plate with hexagonal nuts, and use the magnetic base of the dial indicator to fit on the base of the integral workbench to be processed.

[0029] In this invention, the high rigidity and high stability of the CNC gantry milling and boring machine structure are utilized, and a one-time clamping and multi-axis linkage processing scheme is adopted to process the guide surface of the integral worktable base, the end face of the spindle hole and the spindle hole. The modular combination milling cutter and boring cutter required for use are determined according to the integral worktable base, and the stability of the tool during the processing is determined by theoretical calculation. The three-dimensional software design simulates the entire processing process to ensure that there is no interference and error. During processing, a fixed table clamping method is used to monitor the stability of the workpiece during the processing process to avoid the problem of the workpiece affecting the processing accuracy due to displacement during the processing.

[0030] The beneficial effects of the invention are as follows: in the inventive method, the milling process is multi-tooth processing with high rotation speed, and its processing efficiency is higher than the turning efficiency when processing annular planes, which can effectively improve the processing efficiency. The method uses one clamping to complete the processing of all processing surfaces, avoiding the positioning error caused by multiple clampings and improving the processing accuracy. Due to the improvement of processing efficiency and accuracy, the processing cost is effectively reduced in the inventive method. The present invention is suitable for the processing of the integral worktable base of vertical lathes of various specifications and has a wide range of applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic diagram of the integral worktable base of the DVT500 vertical lathe used in the embodiment of the present invention.

[0032] Figure 2 1 is a schematic diagram of a modular milling cutter assembly used in an embodiment of the present invention.

[0033] Figure 3 1 is a schematic diagram of a modular boring tool assembly used in an embodiment of the present invention.

[0034] Figure 4 It is a simplified diagram of the force conditions of the milling cutter rod used in the embodiment of the present invention.

[0035] Figure 5 It is a simplified diagram of the force condition of the boring bar used in the embodiment of the present invention.

[0036] Figure 6 It is a simulation diagram of the guide rail surface milling route used in the embodiment of the present invention.

[0037] Figure 7 It is a simulation diagram of the spindle hole end face milling route used in the embodiment of the present invention.

[0038] Figure 8 It is a simulation diagram of the spindle hole boring route used in the embodiment of the present invention.

[0039] Fig. 9 It is a schematic diagram of the structure of one side of the fixed meter clamp used in the embodiment of the present invention.

[0040] Fig.10 It is a schematic diagram of the structure of the other side of the fixed meter clamp used in the embodiment of the present invention.

[0041] Explanation of the marks in the figure: 1. The first automatic tool change tool taper shank module; 2. The second equal-diameter intermediate module; 3. The module for installing the C-type indexable face milling cutter; 4. The indexable plane compound milling cutter; 5. The second automatic tool change tool taper shank module; 6. The second equal-diameter intermediate module; 7. The double-edged adjustable indexable boring cutter module; 8. The guide surface; 9. The modular milling cutter; 10. The guide surface milling processing route; 11. The spindle hole end face; 12. The modular milling cutter disc after combination; 13. The spindle hole end face milling processing route; 14. The shaft hole; 15. The modular boring cutter after combination; 16. The shaft hole boring processing route; 17. The base of the integral workbench to be processed; 18. The equal-height shims; 19. The T-type quick-release bolts; 20. The shims; 21. The flat pressure plate; 22. The hexagonal nut; 23. The dial indicator; 24. The magnetic base. DETAILED DESCRIPTION

[0042] The specific implementation of the present invention is described below in conjunction with the accompanying drawings and examples to facilitate a better understanding of the present invention.

[0043] Example

[0044] A method for machining a vertical lathe worktable base in this embodiment includes the following steps:

[0045] (1) Determination of the scheme: Based on the analysis of the machine tool structure, it was determined that the high rigidity and high stability of the CNC gantry milling and boring machine structure would be utilized, and a one-time clamping and multi-axis linkage processing scheme would be adopted to process the guide surface of the integral worktable base, the end face of the spindle hole, and the spindle hole.

[0046] (2) This embodiment uses the DVT500 vertical lathe integral worktable base as an example, the guide rail uses 7075 hydrostatic guide rail plate, and the body material is HT250. The diameters of the milling cutter bar and the boring cutter bar are calculated according to the cutting force of the milling spindle end face and the boring spindle hole during fine machining to ensure the stability of the tool during fine machining.

[0047] (2.1) Select the appropriate tool handle and tool body according to the drawing:

[0048] a. DVT500 vertical lathe overall worktable base diagram, such as Figure 1 shown.

[0049] b. Modular combination milling cutter and boring cutter determined according to the overall workbench base drawing, such as Figure 2 , Figure 3 As shown. The modular combination milling cutter includes a first automatic tool change tool taper shank module 1, a second equal-diameter intermediate module 2, a C-type indexable face milling cutter module 3, and an indexable plane compound milling cutter 4. The second equal-diameter intermediate module 2 is installed at the lower part of the first automatic tool change tool taper shank module 1, the C-type indexable face milling cutter module 3 is installed at the lower part of the second equal-diameter intermediate module 2, and the indexable plane compound milling cutter 4 is installed at the lower position of the C-type indexable face milling cutter module 3. The modular combination boring tool includes a second automatic tool change tool taper shank module 5, a second equal-diameter intermediate module 6, and a double-edged adjustable indexable boring tool module 7. The second automatic tool change tool taper shank module 5 and the double-edged adjustable indexable boring tool module 7 are installed at the upper and lower positions of the second equal-diameter intermediate module 6, respectively.

[0050] (2.2) Calculation and selection of milling cutter rod diameter:

[0051] a. Calculation of the cutting force for fine milling of the spindle hole end face (part material: HT250):

[0052]

[0053] Among them, a e is the milling width, take 260mm; f z is the feed per tooth, take 0.6mm; a p is the milling depth, take 0.25mm; d 0 is the diameter of the milling cutter, which is Φ315mm; Z is the number of teeth of the Φ315 milling cutter, which is 2. Calculation: The fine milling cutting force Fc is calculated to be 169N.

[0054] b. Calculation of milling cutter bar deflection:

[0055] Simplify the force on the tool bar into Figure 4 , and according to the deflection formula and the moment of inertia of the solid cylindrical section Perform calculations.

[0056] F=169Nd=Φ125cm, shank diameter

[0057] 1=292mm

[0058] E (elastic modulus, 40Cr) = 200 GPa = 200000 MPa = 200000 N / mm 2

[0059] I (solid cylindrical section moment of inertia) = 1.198 × 10 7

[0060] Calculation: The deflection of the tool bar ω is calculated B =-0.00059mm

[0061] Through the calculation of the tool bar deflection, it can be seen that the influence of the tool bar deflection deformation on the processing during the fine milling process can be ignored.

[0062] (2.3) Calculation and selection of boring bar diameter:

[0063] a. Calculation of radial cutting force for fine boring of spindle hole (part material: HT250):

[0064]

[0065] in, Take 92; a P is the boring depth, take 0.25mm; Take 1.0; f is the feed speed, take 0.16mm / r; Take 0.75; V c is the cutting speed, which is 17.6 mm / min; Take 0; Take 1.

[0066] Calculation: Through calculation, the radial cutting force of the spindle fine boring is Fc=56N.

[0067] b. Simplify the force on the tool bar into Figure 5 , and according to the deflection formula and solid cylindrical sections

[0068] Moment of inertia Perform calculations.

[0069] F=56N

[0070] d = Φ125cm, shank diameter

[0071] l=245mm

[0072] E (elastic modulus, 40Cr) = 200 GPa = 200000 MPa = 200000 N / mm 2

[0073] I (solid cylindrical section moment of inertia) = 1.198 × 10 7

[0074] Calculation: The deflection of the tool bar ω is calculated B =-0.00011mm

[0075] Through the calculation of the tool bar deflection, it can be seen that the influence of the tool bar deflection deformation on the processing during the precision boring process can be ignored.

[0076] (3) Design the machining path of the overall worktable base, including the milling path of the guide surface, the end face of the spindle hole, and the boring path of the spindle hole. Use 3D software to design and simulate the entire machining process to ensure that there is no interference and error. Figure 6 It is a simulation diagram of the guide rail surface milling route. The modular milling cutter 9 is used to operate the guide rail surface 8 according to the guide rail surface milling processing route 10. The guide plate material of the guide rail surface 8 is 7075. Figure 7 It is a simulation diagram of the spindle hole end face milling route. The combined modular milling cutter disc 12 is used to process the spindle hole end face 11 according to the spindle hole end face milling processing route 13. The material of the spindle hole end face 11 is HT250. Figure 8 It is a simulation diagram of the spindle hole boring route. The combined modular boring tool 15 is used to process the shaft hole 14 according to the shaft hole boring processing route 16. The material of the shaft hole 14 is HT250.

[0077] (4) Place the part on a high shim such as the workbench of a CNC gantry boring and milling machine, align it, and use a fixed clamping method to monitor the stability of the workpiece during processing, such as Fig. 9 , Fig.10 As shown, the equal-height shims 18 are placed on the worktable of the CNC gantry boring and milling machine, the base 17 of the integral worktable to be processed is placed on the equal-height shims 18, the shims 20 are placed on the outside of the base 17 of the integral worktable to be processed, the T-type quick-release bolts 19 are placed between the base 17 of the integral worktable to be processed and the shims 20, and are placed in the T-slot of the worktable of the CNC gantry boring and milling machine, the flat pressure plate 21 is placed on the shims 20 and the foot sockets of the base 17 of the integral worktable to be processed, and the T-type quick-release bolts 19 are fixed to the flat pressure plate 21 with hexagonal nuts 22, and the magnetic base 24 of the dial indicator 23 is attached to the base 17 of the integral worktable to be processed.

[0078] (5) Use a CNC gantry boring and milling machine to mill the guide surface and the end face of the spindle hole, and to bore the spindle hole. By precisely controlling the multi-axis linkage of the machine tool, efficient and high-precision processing of the entire worktable base can be achieved.

[0079] (6) Select appropriate tools and cutting parameters to replace traditional turning with milling and boring to improve part processing efficiency (Table 1).

[0080] Table 1 Comparison of cutting parameters and processing time of DVT500 guide surface, spindle hole end face and spindle hole

[0081]

[0082] (7) After processing, the fitter removes burrs and chamfers the parts, and the accuracy is checked by three-coordinate measurement (Table 2).

[0083] Table 2 Comparison of machining accuracy of DVT500 guide surface, spindle hole end face and spindle hole

[0084]

[0085] The above is a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A method for machining a vertical lathe worktable base, characterized in that: The following steps are involved: (1) Based on the analysis of the machine tool structure, it is determined that the high rigidity and high stability of the CNC gantry milling and boring machine structure are utilized to process the guide surface of the integral worktable base, the end face of the spindle hole, and the spindle hole using a one-time clamping and multi-axis linkage processing scheme; (2) Determine the modular combination milling cutter and modular combination boring cutter to be used according to the overall workbench base; (3) Calculate the diameter of the milling cutter bar and boring cutter bar according to the cutting force of milling and boring, and determine the stability of the tool during the processing; (4) Design the processing path of the overall workbench base and use 3D software to simulate the entire processing process; (5) Fix the overall worktable base on the worktable of the CNC gantry boring and milling machine to ensure its levelness and stability; complete the processing of the guide surface and the spindle hole in one clamping to avoid positioning errors caused by multiple clamping; (6) Use fixed-meter clamping to monitor the stability of the workpiece during processing; (7) Select appropriate tools and cutting parameters to improve part processing efficiency; (8) After processing is completed, necessary follow-up processing and precision inspection are carried out.

2. The method for machining a vertical lathe worktable base according to claim 1, characterized in that: The modular combination milling cutter in step (2) includes a first automatic tool changing tool taper shank module, a second equal-diameter intermediate module, a C-type indexable face milling cutter module, and an indexable plane compound milling cutter. The second equal-diameter intermediate module is installed at the bottom of the first automatic tool changing tool taper shank module, the C-type indexable face milling cutter module is installed at the bottom of the second equal-diameter intermediate module, and the indexable plane compound milling cutter is installed at the bottom of the C-type indexable face milling cutter module.

3. The method for machining a vertical lathe worktable base according to claim 1, characterized in that: The modular combination boring tool in step (2) includes a second automatic tool changing tool taper shank module, a second equal-diameter intermediate module and a double-edged adjustable indexable boring tool module. The second automatic tool changing tool taper shank module and the double-edged adjustable indexable boring tool module are respectively installed at the upper and lower positions of the second equal-diameter intermediate module.

4. The method for machining a vertical lathe worktable base according to claim 1, characterized in that: In step (3), the calculation and selection steps of the milling cutter rod diameter are as follows: 3a. Calculate the cutting force of spindle hole end face finishing milling: Among them, a e is the milling width; f z is the feed per tooth; a p is the milling depth; d0 is the diameter of the milling cutter; Z is the number of teeth of the Φ315 milling cutter; 3b. Calculate the deflection of the milling cutter bar: Simplify the force on the tool bar and use the deflection formula and the moment of inertia of the solid cylindrical section Calculate, in the above formula, F is the spindle hole end face fine milling cutting force calculated in step 3a, d is the tool rod diameter, 1 is the tool rod length, E is the elastic modulus, and I represents the moment of inertia of the solid cylindrical section.

5. The method for machining a vertical lathe worktable base according to claim 1, characterized in that: In step (3), the calculation and selection steps of the boring bar diameter are as follows: 3c. Calculate the radial cutting force of spindle hole fine boring: in, Take 92; a P is the boring depth; Take 1.0; f is the feed rate; Take 0.75; V c is the cutting speed; Take 0; Take 1, All represent coefficients; 3d. Simplify the force on the tool bar and use the deflection formula and the moment of inertia of the solid cylindrical section Calculate, in the above formula, F is the spindle hole end face fine milling cutting force calculated in step 3c, d is the tool rod diameter, 1 is the tool rod length, E is the elastic modulus, and I represents the moment of inertia of the solid cylindrical section.

6. The method for machining a vertical lathe worktable base according to claim 1, characterized in that: The operation method in step (5) is to install the equal height washers and washers on the T-type quick-release bolts below the base of the integral workbench to be processed, and fix them on the flat pressure plate with hexagonal nuts, and use the magnetic base of the dial indicator to fit on the base of the integral workbench to be processed.

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