Research on Thermal Compensation of x-Axis Partition of Drilling and Tapping Center Machine Tools

As one of the most commonly used metal cutting machines in modern manufacturing industry, the drilling and tapping center machine tool has an irreplaceable position in modern manufacturing industry due to its high operating speed and fast tool changing speed. However, in the process of machining, the thermal deformation of the x-axis lead screw is caused due to the changes of the ambient end temperature, the wire mother end temperature and the bearing temperature of the motor seat end, resulting in the error of the workpiece. In this paper, through the above three kinds of thermal deformation simulation and experimental data measurement, and then through the analysis and modeling of the experimental data by MATLAB, a scheme of real-time compensation for the thermal error of the x-axis lead screw is proposed. After the compensation, the products produced by an enterprise are verified. The verification results show that the accuracy after the compensation can be improved by 56.25% compared with that before the compensation.

As an important branch of international economic and scientific and technological development, manufacturing industry plays an irreplaceable role in the process of national economic development. In manufacturing industry, metal cutting machine tools, which are one of the material reduction processing, are at the core of development. They have extremely important applications in metal product processing fields such as molds, fixtures, product parts and automation. With the metallization of 3C consumer and wearable electronic products, the number of metal cutting CNC machine tools required by the market has surged. The drilling and tapping center has become one of the best-selling CNC machine tools in the world in recent years because of its high operating The associate editor coordinating the review of this manuscript and approving it for publication was Xi Zhu . speed, fast tool changing speed, and the processing size of 3C products. The accuracy of the processed products is restricted by its design, assembly and other factors. On the premise of ensuring its design and assembly accuracy, the thermal characteristics of the lead screw is still a key issue to be considered [1], [2].
The ball screw pair is the key transmission and positioning part of the CNC machine tool. It belongs to the slender shaft part. Its length diameter ratio is large, and its rigidity is poor. In addition, the difference of installation methods makes it easy to produce thermal deformation during use. Due to the non-uniformity and non-linear characteristics of the thermal deformation of the ball screw pair, the thermal deformation error varies with the use process. In this paper, TC500R drilling and tapping center produced by Shenyang Machine Tool Co., Ltd. is used as the carrier for research. Because the structure of drilling and tapping centers in the market is VOLUME 11, 2023 This work is licensed under a Creative Commons Attribution 4.0 License. For more information, see https://creativecommons.org/licenses/by/4.0/ similar, this equipment can represent the drilling and tapping centers of most manufacturers. The x-axis ball screw is fixed at one end (motor seat end) and supported at the other end (bearing seat end). The fixed end bears axial force and radial force at the same time; The bearing end only bears radial force and can make a small amount of axial floating, which can reduce or avoid the bending due to the dead weight or deformation of the lead screw to a certain extent. This type of structure is the most widely used at present. At present, the servo shafts of small and medium-sized CNC machine tools and vertical machining centers at home and abroad basically adopt this type of structure.

II. INFLUENCE FACTORS OF THERMAL ERROR OF BALL SCREW A. HEAT GENERATED BY BEARING FRICTION AT MOTOR BASE END
Bearing is an important part of CNC machine tool. Its main function is to support the mechanical rotating body, reduce the friction coefficient during its movement and ensure its rotation accuracy. The fast moving speed of the x-axis of TC500R drilling and tapping center machine tool during machining is 48000mm/min, and the maximum cutting speed during cutting is 12000mm / min. the diameter of the ball screw is 25mm, and the pitch is 24mm. The rotational speeds corresponding to the fast moving and the maximum cutting speed are 2000rpm and 500rpm respectively. The fixed end (motor base end) of the x-axis ball screw of TC500R drilling center studied in this paper uses double row angular contact ball bearings and adopts back-to-back installation. The bearing heating calculation is shown in Eq. (1) [2].
where: Q-Calorific value, KW; M -Bearing friction torque,Nmm; n-Bearing speed,r/min. In Eq. (1), M = M 1 + M 2 , M 1 is the torque component of the sliding friction between the bearing ball and the inner and outer rings and the friction between the rolling body and the cage. During the high-speed rotation of the machine tool spindle, this part of the heat source accounts for about 90% of the total heat generated. The calculation formula is shown in Eq. (2); M 2 is the drag torque between rolling element and cage and lubricating oil (grease), and its calculation formula is shown in Eq. (3) [3], [4].
where: f 1 -Bearing type and load factor; P 1 -Calculation load of bearing friction moment, N; d m -Average diameter of bearing, mm; f 0 -Type and lubrication coefficient of bearing; γ -Kinematic viscosity of lubricating oil, mm2/s.
When the x-axis of TC500R drilling center moves rapidly, the speed of the screw is 2000rpm, and the maximum speed during cutting is 500rpm. In this paper, six levels of speed are selected as the experimental conditions for simulation and experiment, which are 2000rpm, 500rpm, 400rpm, 300rpm, 200rpm and 100rpm respectively. According to formula (1) -(3), the heat generation of the bearing at different speeds is calculated, as shown in Table 1.

B. HEAT GENERATED BY BEARING FRICTION AT BEARING SEAT END
For the calculation of bearing calorific value at the bearing seat end, the same 6-stage rotational speed as that at the motor seat end is also selected, and the calorific value of the bearing at different rotational speeds is calculated by formula (1) -(3), as shown in Table 2.

C. INFLUENCE OF ENVIRONMENT AND TEMPERATURE CHANGE OF SCREW NUT END ON BALL SCREW
In the process of x-axis movement, the ambient temperature changes and the rolling friction between the nut and the screw rod and the ball in the middle will cause the temperature of the screw shaft to rise, and the screw shaft will stretch due to the temperature rise, which will lower the positioning accuracy. The calculation formula of the elongation is shown in Eq. (4) [5], [6], [7].
where: l -axial expansion and contraction of the lead screw, mm; ρ-Thermal expansion coefficient, 12 × 10 −6 / • C; t-Temperature change of lead screw, • C; l-Effective length of threaded part, mm. From formula (4), it can be concluded that when the temperature of the lead screw shaft rises by 1 • C, the lead screw shaft extends by 12µm. Generally speaking, the temperature rise of the screw rod due to heat is considered to be 2 • C ∼ 6 • C, the effective length of the x-axis screw rod of TC500R drilling and tapping center is 718.5mm, and its elongation is 17.2µm-51.7µm. And the thermal elongation of the screw rod is 8.6µm.

III. ESTABLISHMENT OF X-AXIS TRANSMISSION EXPERIMENTAL MODEL AND FINITE ELEMENT ANALYSIS A. ESTABLISHMENT OF THERMAL CHARACTERISTIC MODEL OF X-AXIS TRANSMISSION
For a steady-state analysis model, the temperature matrix can be obtained by the matrix equation, as shown in Eq.(5) [8], [9], [10].
Equation (5) is based on two assumptions: 1) The influence of transient is not considered in the steady-state analysis; 2) [K T ] and {Q T } can be a constant or a function of temperature [11], [12], [13]. This formula is based on Fourier's law, that is, the heat flow inside the solid is the basis of [K T ], and the heat flux, heat flux and convection take effect under the boundary condition of {Q T }. Meanwhile, convection is treated as boundary conditions [14], [15], [16].

B. ESTABLISHMENT AND SOLUTION OF X-AXIS TRANSMISSION FINITE ELEMENT MODEL 1) MODEL ESTABLISHMENT
In this paper, the three-dimensional design software UG12.0 is used for the CAD drawing of the x-axis transmission structure, and some structures that have little impact on the thermal analysis results, such as small holes, threaded holes, chamfers and fillets, are simplified and removed. After assembly, they are stored in step format and imported into ANSYS workbench 15.0 for finite element analysis. The correlation in grid division is 100, the element size in sizing is 8mm, and the number of nodes after calculation is 333886, the number of elements is 209957, and the grid is shown in Fig.1.

2) MATERIAL ATTRIBUTE SETTING
Add material properties such as bearing, ball screw and sliding seat in ANSYS Workbench 15.0, and the properties are shown in Table 3.

3) THERMAL STRUCTURAL COUPLING ANALYSIS OF LEAD SCREW AT MOTOR BASE END
In the steady state thermal module of ANSYS Workbench 15.0, after the material properties are set and meshed according to table 3, the data in Table 1 are loaded onto the model. The initial temperature is set to 25 • C for steady-state analysis and solution. After the thermal analysis and postprocessing, the temperature field is obtained, and the obtained results are applied to the nodes as loads. The deformation shown in Fig.2 occurs at the tail end of the lead screw, with a maximum value of 0.0084mm, Moreover, the deformation is no longer increased beyond about 150 mm from the motor base end bearing, which means that the deformation of the lead screw caused by the heat of the motor base end bearing is only within 150 mm, and the deformation of the remaining part is basically the same as that at 150 mm.

4) THERMAL STRUCTURAL COUPLING ANALYSIS OF LEAD SCREW AT BEARING SEAT END
Similarly, after the thermal analysis and post-processing are completed and the temperature field is obtained, the obtained VOLUME 11, 2023 result is applied to the node as a load to obtain the deformation amount as shown in Fig.3, which occurs at the tail end of the lead screw, with the maximum value of 0.00244mm, and is about 120mm away from the motor seat end bearing. The deformation amount is no longer increased, indicating that the deformation of the lead screw caused by the heating of the bearing at the bearing seat end is only within 120mm.

5) THERMAL STRUCTURAL COUPLING ANALYSIS OF BALL SCREW NUT END SCREW
The ball screw and the nut are connected by an intermediate rolling body, usually rolling friction. There are two commonly used ball circulation modes: the ball is out of contact with the lead screw raceway in the reverse circulation process, which is called external circulation; In the whole cycle process, the ball always keeps in contact with each surface of the lead screw is called the internal cycle, and the TC500R driller center machine tool adopts the external cycle mode. After reaching the steady-state temperature, the deformation is as shown in Fig.4, and the maximum deformation is 0.02088mm.

6) ANALYSIS OF THERMAL DEFORMATION OF LEAD SCREW CAUSED BY ENVIRONMENTAL TEMPERATURE CHANGE
In this paper, the initial temperature of the machine tool in the simulation process is 25 • C, and the temperature change of the workshop environment is usually between 0-7 • C, in this paper, 32 • C is selected as the simulation experimental condition. The deformation is shown in Fig.5, and the maximum deformation is 0.02297mm.
The deformation of the lead screw after heating is an important factor affecting the machining accuracy. However, the machine tool is in an environment where the temperature changes at any time and anywhere. The machine tool itself will inevitably consume energy when it works. A considerable part of this energy will be converted into heat in various ways, causing physical changes of various components of the machine tool. This paper mainly analyzes the friction heat of the bearing at the motor seat end, the friction heat of the bearing at the bearing seat end, the conduction mode of the friction heat between the screw head and the lead screw, and the influence of the change of the ambient temperature on the deformation of the x-axis lead screw through the thermal convection mode.

IV. EXPERIMENTAL VERIFICATION AND ESTABLISHMENT OF ZONING COMPENSATION MODEL
The x-axis stroke of TC500R drilling and tapping center machine tool is 500mm. The experimental condition is to use laser measuring instrument to measure the position error every 50mm. The positions are 0mm, 50mm, 100mm, 150mm, 200mm, 250mm, 300mm, 350mm, 400mm, 450mm and 500mm respectively. The 0mm position is close to the motor base end and the 500mm position is close to the bearing base end. The layout of the laser measuring instrument is shown in Fig.6. The laser measuring instrument is arranged in the front of the machine tool. Adjust the spindle of the machine tool to a proper position, arrange a laser mirror 1 with a constant position, and arrange a laser mirror 2 on the workbench that can move with the workbench. As the workbench moves at the position of 0-500mm, the laser beam emitted by the laser measuring instrument passes through the mirror 1 and reaches the mirror 2. After reflection, it is returned to the laser measuring instrument by the mirror 1, So as to measure the data of the movement of the corresponding position of the table, and then reflect the deformation of the lead screw caused by the temperature change of the lead screw.

2) TEMPERATURE SENSOR LAYOUT
During the experiment, the temperature sensors are arranged at four positions in the motor base, bearing base, spindle and environment of the machine tool. The layout positions of the four temperature sensors are shown in Fig.7. In order to ensure that the deformation of the lead screw caused by the temperature change of the single position is measured separately under the condition that the temperature of the other three positions is not changed, the adjustable temperature chiller and the metal cover are used in this experiment to keep the temperature of the motor base, the screw nut and the bearing base constant. As shown in Fig.8, the ambient temperature is adjusted by the air conditioner. During the experiment, the rapid movement (G00) and cutting feed (G01) are used to work together. In order to simulate the real cutting process, the proportions of the rapid movement and cutting speed in this experiment are shown in Table 4.

3) INFLUENCE OF BEARING TEMPERATURE CHANGE ON LEAD SCREW DEFORMATION
The layout position of the temperature sensor at the motor base end is as shown in No.9 in Fig.7. A laser measuring instrument is used to measure the deformation of the lead screw for every 1 • C change in temperature. The ambient temperature is treated with air conditioner for constant temperature, and the screw nut and the bearing base are treated with a cold dryer and a metal cover for constant temperature, so as to ensure that the temperature change is only the temperature change of the bearing at the motor base end. The deformation at different positions of the screw rod caused by the temperature change is shown in Table.5, The change trend is shown in Fig.9.
It can be seen from table 5 that the deformation of the lead screw caused by the heating of the bearing at the end of the motor base only affects the lead screw part within 150mm near the end of the motor base, and has almost no effect beyond 150mm. Starting from the initial temperature of 25 • C, the time for each rise of 1 • C gradually increases, and after reaching 32 • C, it runs for 60min without obvious temperature rise, which can be considered as reaching the thermal equilibrium state.

4) INFLUENCE OF BEARING TEMPERATURE CHANGE AT BEARING SEAT END ON DEFORMATION OF LEAD SCREW
The layout position of the temperature sensor at the bearing seat end is as shown in No.3 in Fig.7. For every 1 • C VOLUME 11, 2023 change in temperature, a laser measuring instrument shall be used to measure the deformation of the lead screw. The treatment methods of the ambient temperature, the temperature of the lead screw and the temperature of the motor seat are the same, so as to ensure that the temperature change is only the temperature change of the bearing at the bearing seat end. The deformation at different positions of the lead screw caused by the temperature change is shown in Table 6, and the change trend is shown in Fig.10.
It can be seen from table 6 that the deformation of the lead screw caused by the heating of the bearing at the end of the bearing seat only affects the lead screw within 100 mm from the end of the bearing seat, and has almost no effect beyond 100 mm. Starting from the initial temperature of 25 • C, the time for each rise of 1 • C gradually increases, and after reaching 30 • C, it runs for 60min without obvious temperature rise, which can be considered as reaching the thermal equilibrium state.

5) INFLUENCE OF THE TEMPERATURE CHANGE OF THE MOTHER SCREW ON THE DEFORMATION OF THE LEAD SCREW
The layout position of the temperature sensor at the screw head end is shown in No.7 in Fig.7. For every 1 • C change in temperature, a laser measuring instrument is used to measure the deformation of the screw head. The treatment methods of the ambient temperature, the motor seat temperature and the bearing seat temperature are the same as above, so as to ensure that the temperature change is only the temperature change at the screw head end. The deformation at different positions of the screw head caused by the temperature change is shown in Table 7, and the change trend is shown in Fig.11. It can be seen from table 7 that the deformation of the lead screw caused by the friction heat of the rolling body at the end of the thread mother affects the whole lead screw. Starting from the initial temperature of 25 • C, the time for each rise of 1 • C gradually increases, and after reaching 32 • C, it runs for 60min without obvious temperature rise, which can be considered as reaching the thermal equilibrium state.

6) INFLUENCE OF AMBIENT TEMPERATURE ON THE DEFORMATION OF LEAD SCREW
The experimental process of the influence of environmental temperature change on the deformation of the lead screw is different from the above three position measurement methods. The air conditioner is used to intervene the external environment of the machine tool, starting from 25 • C and increasing by 1 • C every 20 minutes. At the same time, the laser measuring instrument is used to measure the deformation of the lead screw at different positions. Considering that the maximum temperature in the above is 32 • C, the ambient temperature is also raised to the maximum 32 • C in this experiment. The layout position of the temperature sensor at the ambient end is as shown in No.1 in Fig.7. The processing methods of the temperature of the screw mother, the temperature of the motor seat and the temperature of the bearing seat are the same as above, so as to ensure that the temperature change is only the change of the ambient temperature. The deformation amount of the screw rod at different positions caused by it is shown in Table 8, and the change trend is shown in Fig. 12.
It can be seen from Table 5, Table 6, Table 7, Table 8 and their corresponding trend charts that the temperature changes of motor base end bearing, bearing base end bearing, nut end and environmental end have an impact on the deformation of the lead screw, and the experimental data has a great correlation with the data obtained from the finite element analysis. Among them, the finite element analysis data of the motor base end bearing temperature change is within 150mm of its adjacent range, which is basically consistent with the experimental data. The finite element analysis data of the deformation is 0.0084mm, and the experimental data is 0.0069mm, which is 21.7% larger than the experimental data;  The finite element analysis data of the bearing temperature change at the bearing pedestal end is within the range of 120mm adjacent to it, and the experimental data is within the range of 100mm adjacent to it. The finite element analysis data of the deformation is 0.00244mm, and the experimental data is 0.0031mm, which is 21.3% smaller than the experimental data; The maximum deformation of the screw end obtained by finite element analysis of the temperature change of the nut end is 0.02088mm, and the experimental data is 0.0252mm, which is 17.1% smaller than the experimental data; The maximum deformation is 0.02297mm according to the finite element analysis of temperature change at the environment end, and the experimental data is 0.0282mm, which is 18.5% smaller than the experimental data.
After comparing the data obtained from the above finite element model analysis with the experimental data, there is a certain deviation, which is mainly caused by the temperature field fluctuation caused by the convection between the temperature field of each component and the air or bearing grease. The deviation is acceptable in the accuracy control of VOLUME 11, 2023 CNC machine tools, and will not be detailed here. Among them, the change of ambient temperature has the greatest impact, the change of bearing block temperature has the least impact, and the change of motor block temperature only affects its adjacent end within 150mm.

B. DATA ANALYSIS AND MATHEMATICAL MODELING
According to the analysis of table 5, table 6, table 7, table 8 and Fig.9, Fig.10, Fig.11 and Fig.12, it can be seen that the maximum temperature rise at the bearing seat end is 30 • C, and the maximum deformation occurs at 500mm, with the deformation of 3.1µm. And the influence is only within the range of 100mm at the end of the lead screw, which can be ignored in machining.
The change of the ambient temperature has the most prominent influence on the overall deformation, and the environment is the basis of other temperatures. The temperature rise of the bearing at the motor seat end, the bearing at the bearing seat end and the temperature rise of the friction between the screw head and the lead screw are all based on the ambient temperature rise. In this paper, the ambient temperature is taken as the basis for the deformation of the lead screw, and the temperature rise of other parts is superimposed, and then the deformation amount at 0mm, 50mm, 100mm, 150mm, 200mm, 250mm, 300mm, 350mm, 400mm, 450mm and 500mm is calculated, which is automatically compensated in the pitch compensation module of the CNC system, so as to reduce the processing error caused by thermal deformation.

1) AMBIENT END TEMPERATURE ANALYSIS
The extension of the lead screw caused by the change of the ambient temperature can be well reflected by the change trend of the deformation by using the cubic polynomial in MATLAB. The mean square deviation of the fitting polynomial at 11 positions is less than 0.5µm. Within the allowable range, the cubic polynomial is shown in Eq. (6).
where: F h (S, T)-Axial deformation of lead screw under the influence of ambient temperature, mm; S -Lead screw position, mm; T -Ambient temperature, • C; A hS , B hS , C hS , D hS -Coefficient of cubic polynomial, as shown in Table 9.

2) TEMPERATURE ANALYSIS OF THE MOTHER WIRE END
The deformation of the lead screw caused by the temperature change of the thread mother end is generated on the basis of the deformation caused by the change of the ambient temperature. It is fitted in MATLAB, and the mean square deviation of the fitting polynomials at 11 positions is less than 0.5µm. Within the allowable range, the cubic polynomial is shown in Eq. (7). where: F s (S, T 1 ) -Axial deformation of the lead screw under the influence of the temperature of the lead screw, mm; S -Screw position, mm; T 1 -Difference between the temperature of the mother wire and the ambient temperature, • C; A sS , B sS , C sS , D sS -Cubic polynomial coefficients, as shown in table 10.

3) TEMPERATURE ANALYSIS OF BEARING AT MOTOR BASE END
The deformation of the lead screw caused by the temperature change of the bearing at the motor base end is also generated on the basis of the deformation caused by the change of the ambient temperature, and has almost no effect beyond 150mm. Fit the four positions of 0mm, 50mm, 100mm and 150mm in MATLAB, and the other seven positions can be considered as the same as the deformation value at 150mm. The mean square deviation of fitting polynomials at four positions is less than 0.5µm. Within the allowable range, the cubic polynomial is shown in Eq. (8).
where: F d (S, T 2 ) -Axial deformation of lead screw under the influence of bearing temperature of motor base,; S -screw position,; T 2 -Difference between bearing temperature at motor base end and ambient temperature,; A dS , B dS , C dS , D dS -Coefficient of cubic polynomial, as shown in Table 11.

4) MATHEMATICAL MODELING OF LEAD SCREW DEFORMATION
According to the above analysis, the thermal deformation of the lead screw is mainly composed of three parts, one is the change of the ambient temperature, and this part is the main source of the deformation; The second is the deformation of the screw rod caused by the temperature rise of the master screw; The third is the deformation of the lead screw caused by the friction heat of the bearing at the motor base end, and the deformation of the lead screw caused by this part is within 150 mm from the bearing. The deformation at the position exceeding 150 mm can be considered to be the same as that at 150 mm. The calculation of the comprehensive deformation of the lead screw is shown in Eq. (9) and Eq. (10).
(1) When S ≤ 150mm, the deformation amount F(S) can be calculated according to Eq. (9): (2) When S > 150mm, the deformation amount F(S) can be calculated according to Eq. (10): where: F(S) -Comprehensive deformation of lead screw, mm; F h (S, T) -Axial deformation of lead screw under the influence of ambient temperature, mm; F s (S, T 1 ) -The axial deformation of the screw under the influence of the temperature of the mother screw, mm; F d (S, T 2 ) -Axial deformation of lead screw under the influence of bearing temperature of motor base, mm.
During the operation of the machine tool, the data is compensated to the 11 macro variables # 500 to # 510 by Eq. (9) and Eq. (10) every 5min. The screw compensation program of the CNC system will automatically call the 11 variable values, so as to achieve the purpose of real-time zoning thermal error compensation of the lead screw and improve the machining accuracy of the CNC machine tool [17], [18].

V. VERIFICATION OF CUTTING AFTER COMPENSATION
Through the real-time temperature monitoring of the temperature sensor, the calculated partition compensation value is compensated into the system screw compensation data, which can effectively detect and compensate the x-direction error of the processed part caused by the thermal extension of the x-axis lead screw. In the verification process, the x-direction dimension of the backplane produced by an enterprise is 277.74±0.02mm as the verification object. The production of the back plate adopts the production method of producing one product with a single fixture. The processing time of the TABLE 12. Comparison of dimensions before and after compensating for milling a product. VOLUME 11, 2023 single-mode product is 226s. The dimension verification data is shown in Table 12.
It can be seen from table 12 that before compensation, 20 mold products were processed, and the size change was 0.064mm; After the compensation, the size change is 0.028mm. It can be seen that after the compensation measures are implemented, the size change is reduced from 0.064mm to 0.028mm, a decrease of 56.25%. With the increase of processing time, the size change without compensation will be further increased, which will seriously affect the product yield. However, the size change after compensation is more uniform, and the error compensation can be carried out in real time to ensure that the product size is within the controllable range.
In the process of precision product processing, there are many factors that affect the product size error, such as the thermal deformation of the lead screw, the clamping accuracy error of the fixture, the tool swing error, the micro deformation of the workpiece surface caused by the cutting heat in the cutting process, and the reasonableness of the tool path selection. In this experiment, the thermal deformation of the screw rod is mainly studied and error compensation is made. Other secondary factors that cause the dimensional accuracy of the product are selected under the same experimental conditions, so the dimensional error cannot be completely eliminated. In processing, the reader can optimize the above-mentioned secondary factors after compensating the thermal deformation of the lead screw, so as to further improve the processing accuracy and ensure the product quality.

VI. CONCLUSION
This paper analyzes the x-axis thermal error sources of the existing TC500R machine tool, which mainly come from the environment end, the thread end and the motor seat end bearing. Under the joint action of the three, the x-axis thermal error of the TC500R drilling center is caused. Through mathematical modeling and curve fitting of cubic polynomials, the compensation model as shown in Eq. (9) and Eq. (10) is obtained. Real time compensation is performed every 5min to compensate the value into the 11 screw compensation macro variables of the numerical control system.
Through the cutting verification after compensation, the machining of 20 mold products shows that the numerical change of the length dimension of 277.74±0.02mm is reduced from 0.064mm before compensation to 0.028mm after compensation, and the error is reduced by 56.25%. Moreover, the later the machining, the greater the error of the machine tool without error compensation, and the error of the machine tool after compensation is within the controllable range.
TC500R is a classic drilling and tapping center machine tool. The research method in this paper can provide technical reference for other types of machine tools in the field of zonal thermal error compensation.
LIANZHOU YU was born in 1987. He received the degree from Northeastern University, in 2012, and the master's degree from the School of Mathematics Engineering, Shenyang Urban Construction University. He is currently working as an Associate Professor with the School of Mathematics Engineering, Shenyang Urban Construction University. His research interests include numerical control technology and machine tools, mechanical design, and manufacturing. He has published more than 20 articles, more than 20 patents, prepared four textbooks, presided over one general project funded by Liaoning Natural Science Foundation, and one general project funded by Liaoning Provincial Department of Education. He has won Shenyang Science and Technology Research Achievement Award.
QI LI was born in 1984. She received the degree from Dalian Maritime University, in 2010. She is currently working as an Associate Professor with the School of Mathematics Engineering, Shenyang Urban Construction University. Her research interests include machine tools, mechanical design and manufacturing, and intelligent logistics system planning. She has participated in six national and provincial-level trainings, presided over and participated in more than ten provincial and municipal education and scientific research projects, published more than ten academic papers, one national utility model patent, one book, and two textbooks, and won five national and provincial awards.
JIPING LI was born in 1984. He received the degree from Northeastern University, in 2009, and the master's degree from the School of Mathematics Engineering, Shenyang Urban Construction University. He is currently working as a Lecturer with the School of Mathematics Engineering, Shenyang Urban Construction University. He has published more than ten papers and two patents. His research interests include hydraulic and pneumatic transmission, CNC machine tools, and CNC technology.
LI SHANG was born in 1979. She received the degree from the Shenyang University of Technology, and the master's degree from the Teaching and Research Department. She was an Associate Professor and the Director of the Teaching and Research Department. She has published more than 20 papers and more than ten patents. Her research interests include hydraulic transmission and control, mechanical design, and manufacturing.
GANG CHEN was born in 1985. He received the bachelor's degree from the Shenyang University of Chemical Technology, in 2008. He is currently working as a Senior Engineer with the Design and Research Institute, Shenyang Machine Tool Company Ltd. He has published ten papers and nine patents. His main research interests include thermal deformation of CNC machine screw and vibration of CNC machine spindle. He has won the China Design Excellence Award. VOLUME 11, 2023