Comparative Analysis of the Reliability and Durability of TIC and NSK Ball Screws for Enhanced Process Optimization

Abstract

Ball screws play an important role in machine tools by converting rotational motion into precise linear motion. This study evaluates and compares ball screws from two companies (TIC and NSK) through simulations and experimentation to assist in the selection process. Simulation results show that TIC exhibits a lower maximum temperature (32.6 °C) and axial deformation (119.3 μm) compared to NSK (34.05 °C and 174 μm, respectively), indicating superior thermal performance and deformation properties. An accelerated life test conducted over 240 h further demonstrates that TIC maintained more stable temperatures during continuous operation. Additional tests on the TIC ball screw include thermal displacement which is 13.5 μm after 2000 cycles of reciprocating motion. Friction torque fluctuation rate which ranges from 11.6% to 19.9%, and test bench positioning repeatability experiment shows a mean deviation of 4.99 μm from the target position. Overall, the results from this work contribute to process optimization by guiding the selection of ball screws based on their thermal performance and durability, ultimately enhancing machine tool accuracy and reliability.

1. Introduction

Ball screws are essential to modern industry and are susceptible to temperature variations like any other machine tool component, resulting in thermal errors in motion drive systems [1]. Approximately, 40% to 70% of production errors are caused by thermal deformation in machine tools which operate at high speed and high precision resulting in manufacturing and processing faults [2]. The TIC (Tongil Industrial Co., Gyeongsang, Republic of Korea) ball screws are designed for use in the machine tools, industrial machinery, defense systems, and medical equipment. Their products are known for their durability and adaptability to various applications which are suitability for high-load and robust operational conditions. In contrast, NSK (Nippon Seiko Kabushiki-gaisha, Shinagawa, Japan) manufactures ball screws used in machine tools, injection molding machines, conveyors, semiconductor manufacturing equipment, and surgical robotics. Their focus is on delivering high precision and performance in environments that require consistent accuracy and reliability.

Thermal errors in the ball screw are commonly investigated using the finite element method (FEM) [3]. Zhang et al. modeled the position-dependent temperature rise and resulting thermal elongation under varying rotational speeds using thermodynamic principles, with experimental results closely matching the theoretical predictions [4]. Weck M et al. [5] illustrated the potential and constraints of determining the temperature of machine tools using FEM. Xu et al. [6] discussed the thermal error of the ball screw system and the efficiency of the air-cooling with the help of FEM. Furthermore, X Min et al. [7] utilized the FEM thermal model for ball screws, where the thermal resistance between the components like housing and the bearing was investigated to find the temperature of the feed drive system. Li et al. [8] outlined an error compensation technique for the time-varying positioning inaccuracy in machine tools by simulations and experiments. He further modeled the thermal expansion across segmented regions of the screw shaft to better account the uneven heat distribution, achieving improved accuracy in compensated machining [9]. A temperature field model based on heat conduction equations with temperature-dependent parameters has also been shown to accurately predict thermal error, with minimal deviation from experimental results [10]. Moreover, Oyanguren et al. [11] described a FEM-based thermo-mechanical model that explains a numerical modelling approach predicting the preload variations due to temperature increases in double nut ball screw drives. Huang et al. [12] used a stretching bar thermal deformation model to examine the relationship between heat quantity and deformation, later validated using FEM. Recent studies have further improved the model by integrating thermal deformations into dynamic models of ball screw systems to assess how system responses to change in speed, excitation forces, and platform position [13]. Studies from the previous authors conclude that the numerical tools can be used to predict thermal and operation behavior of the ball screw while considering the appropriate simulation models. Therefore, in this study a combination of both numerical and experimental techniques were implemented.

Furthermore, friction torque has a major impact on power consumption, position precision, and overall efficiency of ball screws, thus understanding this parameter helps in achieving high accuracy and efficiency in manufacturing [14]. Xu et al. [15] carried out a detailed investigation that included experimental and creep analysis to investigate the friction properties of the ball screw. He discovered a nonlinear relationship between the ball screw parameters and the frictional behavior. Taking into account factors like geometry, assembly, and operating conditions, Oh et al. [16] created a mathematical formula for viscous friction and applied load acting on the components. A coupling connection between friction torque, rotational speed, and preload was created by Zhao et al. [17], where various parameters are examined that affect friction torque. Recent work by Zhang et al. [18] further explored how grease lubrication behaves under dynamic conditions in ball screw mechanisms, showing that variations in screw speed and motion frequency influence film thickness and friction torque at the ball-groove interface.

Although our work is focused on the thermal and mechanical performance evaluation of the ball screws using experimental and numerical based approach. Recent studies have also explored complementary data-driven approaches. For instance, Xie et al. [19] utilized transfer learning and adaptive normalization in fault diagnosis to address sensor placement limitations and noise. Similarly, Zhang et al. [20] combined physical modeling with machine learning to predict ball screw lifespan by integrating preload and precision metrics. Chen et al. [21] introduced visual inspection methods with domain adaptation to detect surface defects under contamination. While these AI-driven strategies differ from the methodology used in this paper, they can be further used to improve reliability and operational performance.

The literature study provides an insight into how temperature and torque influence the precision of ball screws, but there’s a clear gap in understanding the performance of ball screws from different manufacturers. Most of the past research is focused on modeling the thermal effects, frictional behavior, and error compensation using simulation-based studies. However, there’s a lack of experimental analysis that directly compares ball screw’s thermal and frictional characteristics from different manufacturers.

Thus, this study aims to bridge that gap by evaluating the simulation results combined with experimental data to calculate the thermal performance and mechanical stability of the TIC and NSK ball screws. Unlike previous work that was more theoretical, this research provides a way to combine both in such a way that reflects the real working conditions, which is achieved by analyzing temperature fluctuations, axial deformation, and long-term durability testing. The result from this study contributes to the process optimization by giving detailed comparison in terms of heat generation, durability and thermal deformation, thus increasing overall efficiency and precision of the ball screw in high-speed precision manufacturing.

2. Materials and Methods

2.1. Model and Material Description

The TIC and NSK ball screws were designed using the CAD software CATIA V5, shown in Figure 1. The models were created based on the specifications of a milling machine (DVF5000) for its X, Y and Z axes. Thus, each axis had a few differences in dimensions. The total length of the ball screw shaft of the X-axis was 1127 mm, the Y-axis was 1022 mm, and the Z-axis was 932 mm.

Material properties were assigned according to their compositions. The NSK ball screw is made from AISI4150, a medium-carbon and chromium-molybdenum alloy steel known for its high strength, and wear resistance. The material assigned to the TIC ball screw is SCM445H, a chromium-molybdenum (Cr-Mo) alloy steel commonly used in high-strength applications requiring excellent toughness, wear resistance and heat resistance. The detailed properties of both materials are given in

Table 1. Mechanical properties of AISI4150 and SCM445H alloy steel.

Properties	AISI4150	SCM445H
Density (kg/m3)	7850	7700
Poisson’s ratio	0.27–0.3	0.27–0.3
Tensile strength (MPa)	731	650–880
Thermal conductivity (W/m·K)	44.5	36
Yield strength (MPa)	380	350–550
Specific heat capacity (J/g-°C)	0.47	0.46
Coefficient of thermal expansion (K−1)	1.3 × 10⁻⁵	10 × 10⁻⁶
Young’s modulus (GPa)	190	200

.

2.2. Simulation of NSK and TIC Ball Screw

For the simulation study ANSYS 2024 R1 finite element software was implemented. Structural and thermal analyses were performed for both ball screws, TIC and NSK. The boundary conditions are detailed in Figure 2. In structural analysis, displacement was applied to one end of the shaft while cylindrical support was applied to the other end to measure the axial elongation of the ball screw. A rotational velocity of 500 rpm was applied to the shaft that replicates the typical working operational speed of the ball screw in the milling machine.

In the thermal analysis, physical contacts between the balls and the screw, as well as between the balls and the nut, were not modeled using mechanical contact elements. Instead, a thermal-load substitution approach was employed due to the geometric complexity and contact variability within the ball-nut interface. The frictional effects at these interfaces were represented as heat generation, calculated using established equations [22].

$$H_{ballscrew}=0.12·\pi ·f_0·\upsilon ·n·M_{ballscrew}$$

(1)

where, $f_0$ is the lubrication coefficient (0.002), $\upsilon$ is the kinematic viscosity of the lubricant (1400 mm²/s), $n$ is the rotational speed (500 rpm), and $M_{ballscrew}$ denotes the friction torque. The heat generation was estimated as Q = T⋅ω, where T = 0.195 N·m and ω = 52.36 rad/s, yielding 10.22 W, assuming full conversion of frictional work into heat. Based on known Nusselt number correlations, convective heat transfer coefficients of 5 W/m²K and 6.588 W/m²K were subjected to the exposed ball screw surfaces and nut-shaft gap areas, respectively. The ambient temperature was kept at 22 °C; radiative heat transfer was omitted since the operational temperature range dominated conduction and convection mechanisms. For both SCM445H and AISI4150 alloys, material-specific thermal properties were applied, including thermal conductivity values of 36.0 W/m-K and 44.5 W/m-K, respectively, and specific heat capacities of 0.46 J/g-°C and 0.47 J/g-°C.

A mesh convergence study was conducted at the beginning by refining the element size down to 0.5 mm, where changes in temperature and displacement were within ±2%, ensuring solution accuracy in line with established best practices [23].

2.3. Mechanical Tests

In this section, different tests were performed on commercially available TIC and NSK ball screws including thermal displacement per 1 m of ball screw, friction torque fluctuation rate, test bench positioning repeatability and accelerated life test. Further details of each test are explained in the following sections.

2.3.1. Thermal Displacement per 1 m of TIC Ball Screw

In this test a load of 200 kg or more is applied to the ball screw’s travel section in the performance test apparatus, as shown in Figure 3.

The DVF5000 X-axis ball screw, with a total length of 1127 mm was used for measurement. Reciprocating travel was performed at a feed speed of 1000 rpm within the ball screw, with the motor reference set for a reciprocating travel section of 1 m. A warm-up operation was carried out for more than 100 cycles before the test began. After more than 2000 cycles of reciprocating travel, the thermal displacement value was examined inside the comprehensive performance test apparatus.

2.3.2. TIC Ball Screw Friction Torque Fluctuation Rate

The test setup consisted of precision torque measurement device which calculates the force required to hold the nut in place while the shaft of the ball screw rotates. The experimental setup is shown in Figure 4.

The deviation in torque during operation was recorded to make sure that it stays within the permitted range of torque variation. The seals were then removed from the ball screw and the rotational speed of 100 rpm was set for the duration of the test. The experiment was conducted in a controlled environment where the temperature and humidity were kept constant.

The frictional torque fluctuation rate of five ball screws including X-axis #1, Y-axis #1 and #2, and Z-axis #1 and #2 were noted. The torque fluctuation was calculated by determining the difference between the maximum and minimum torque values, as measured by a precision torque measuring device and the torque value discussed is the highest value that is measured.

2.3.3. Test Bench Positioning Repeatability

The test was conducted by assembling a ball screw of length 1091 mm and installing it into a performance testing machine shown in Figure 5.

Before starting the experiment, a suitable warm-up procedure was performed. A laser interferometer was then installed on the linear section of the travel stroke of the performance test machine. Measurements were taken along a 500 mm section of the travel stroke. The target points were set at intervals of 0, 100, 200, 300, 400, and 500 mm. Five cycles of back-and-forth travel were carried out, with measurements made at each target location, to evaluate the repeatability precision.

2.3.4. Accelerated Life Test

Multiple durability tests were conducted to evaluate the long-term performance of the TIC ball screws and its comparison with NSK ball screws. The specifications of both ball screw components are given in

Table 2. TIC and NSK ball screw specifications.

Specification	TIC Ball Screw	NSK Ball Screw
Z-axis model	YEF4010-R700-C3-1091	W4007P-105PSS-C3Z10
Ball diameter (mm)	6.35	6.35
Preload method	Oversize Preload	Oversize Preload
Number of turns	3.75 Turns × 2	5.75 Turns
Lead (mm)	10	10
Accuracy grade	C3	C3
Preload amount (kgf)	3.0	5.0
Basic dynamic load rating (kgf)	4590	3741

. The Z-axis was selected due to its susceptibility to vertical loading stress. The C3-grade accuracy was chosen as it is commonly used in industrial CNC tools, ensuring our results are transferable to real-world use cases.

To evaluate the durability of the ball screws, first the spring load test was conducted. This test was used to measure the axial deformation of the ball screw under progressively increasing loads. The axial deformation is measured following the general procedure of ASTM E8/E8M-16a, adapted for compression testing with calibration, referencing prior validated studies from our lab. The test was performed using an Instron 8801 servo-hydraulic testing machine (Instron Corp., Norwood, MA, USA) with a maximum load capacity of 100 kN and accuracy within ±0.5%, as shown in Figure 6. In this case, a load of 2168 kg was applied, causing a 1.7 mm reduction in the length of the ball screw and 83.6 mm of deformation in the full testing assembly, including fixtures and base compliance. This load value is then further used in the accelerated life testing process.

Next, the Accelerated Life Test (ALT) was conducted, where the purpose was to replicate long-term operational conditions in a shorter amount of time. The ALT experiment was carried out on a custom-built rig integrating a Yaskawa Sigma-7 servo motor system and THK LM Guide. The test protocol was inspired by IEC 60068-2-2 standards, supplemented with TIC and NSK internal specifications. The test attempts to speed up the wear and failure processes by exposing the ball screws to extreme conditions such as high loads, speeds, and temperatures. The detailed labeling of the ALT test equipment is shown in Figure 7.

The ALT was performed on the Z-axis ball screw of the machine where the operating speed was 250 rpm with a stroke length of 40 mm. Using the mathematical equation (based on the ISO/CD 3408-5 standard [24]), the total operating time in hours was calculated.

$$L={\left({\displaystyle \frac{C_a}{P_m{f}_w}}\right)}^3\times {10}^6$$

(2)

$$L_h={\displaystyle \frac{L}{60·N_m}}$$

(3)

where $L$ is the theoretical life and $L_{h }$ is the actual operating life of the ball screw, $C_a$ is basic dynamic load, its value is 4590 kgf, $P_m$ is equivalent axial load with a value of 2168 kgf and $f_w$ is load factor which is 1.2 in this case. After solving the equation with the mentioned values, we have the theoretical operating life of the ball screw. Then it can be further used in calculating the actual operating life of the ball screw where $N_m$ is the rotational speed. The actual operating life $\left(L_h\right)$ of the ball screw was found to be 457.5 h, indicating the maximum time in hours the ball screw can work in specific conditions.

3. Results

3.1. Simulation Results of NSK and TIC Ball Screw

The simulation results for the NSK ball screw are presented in Figure 8. For the X-axis ball screw (1127 mm), the maximum temperature was recorded 34.05 °C with the axial displacement of 174 µm while for the Y-axis ball screw (1022 mm), the temperature was recorded 32.8 °C and the axial displacement of 154 µm. Similarly for the Z-axis ball screw (932 mm), the temperature was noted 31.8 °C and the axial displacement of 142 µm.

The simulation results of the TIC ball screw are presented in Figure 9. For the X-axis ball screw (1127 mm), the temperature of 31.7 °C with the thermal displacement of 119.3 µm was recorded while for the Y-axis ball screw (1022 mm), the temperature of 32.6 °C and the thermal displacement of 118.1 µm was recorded. Similarly for the Z-axis ball screw (932 mm), the temperature reading of 30.6 °C and the thermal displacement of 87.9 µm was noted.

The difference in the temperature and thermal displacement are due to the material differences and the structural design of TIC and NSK ball screws. The AISI4150 material used in NSK ball screws has higher thermal conductivity and coefficient of thermal expansion (1.3 × 10⁻⁵ K⁻¹) meaning more heat accumulation and thermal displacement. While SCM445H used in TIC ball screw has lower thermal conductivity and coefficient of thermal expansion (10 × 10⁻⁶ K⁻¹) leading to reduced heat accumulation and retention thus making it more thermally stable. Furthermore, the higher Young’s modulus of SCM445H (200 GPa) compared to AISI4150 (190 GPa) contributes to the reduced deformation in TIC ball screws.

The structural design of TIC ball screws also enhances its performance. The number of turns per lead in the TIC ball screw is 3.75 turns × 2, compared to 5.75 turns of the NSK ball screw, affecting its load distribution and heat generation. Also, the TIC ball screws have a higher basic dynamic load rating (4590 kgf) vs. the NSK ball screws (3741 kgf) which affects their ability to support higher loads with minimal deformation.

3.2. Mechanical Test Results

In this section, the results of each test are explained.

3.2.1. Thermal Displacement Test Results

Previous studies have confirmed that ball screws experience measurable thermal elongation during continuous operation, where temperature rise and thermal expansion are key factors influencing performance [10]. For instance, experimental investigations have demonstrated thermal elongations in the range of approximately 30–140 µm, depending on rotational speed and running distance [4]. These findings highlight that thermal deformation of ball screws occurs at the micrometer scale under typical operating conditions. In this study, a similar trend was observed under the applied testing conditions.

The test results obtained from the experiment are shown in Figure 10. The graph illustrates that after approximately 250 cycles, the temperature remained relatively stable with only minor fluctuations. The maximum thermal displacement measured during the experiment was 13.5 µm, consistent with the micrometer-level deformations reported in the literature [4].

3.2.2. Friction Torque Fluctuation Test Results

The obtained experimental results are shown in Figure 11, highlights the maximum and minimum torque values of each ball screw. The Y-axis #1 ball screw was found to have the highest maximum and minimum torque values while Z-axis #1 ball screw was observed to have the lowest maximum and minimum torque values. Similarly, the Y-axis #2 ball screw was tested to have the highest torque fluctuation rate while Z-axis #2 ball screw experienced the lowest torque fluctuation. These results aligned with the general behavior discussed in the literature, where friction torque characteristics vary based on lubrication conditions, loading, and rotational speed [17,18].

3.2.3. Positioning Repeatability Test Results

After performing the test for calculating the positioning precision, the results are discussed with the help of graphs as shown in Figure 12. In the graph the target position is plotted on the X-axis while the deviation is shown on the Y-axis. Furthermore, the repetition of the data from different tests is highlighted with the confidence band (gray color). The mean deviation from the actual position is noted to be 4.99 µm.

Additionally, Figure 13 shows repeatability in both positive and negative directions. Mean deviation/error was also monitored. In the negative direction, the error observed was the lowest at point 5 (400 mm) and maximum at point 6 (500 mm). While in the positive direction, the lowest observed error was at point 4 (300 mm) and the highest at point 6 (500 mm). These findings experimentally confirm the influence of mechanical design parameters, such as stiffness and preload on positional repeatability [25].

3.2.4. Results of Accelerated Life Test

The ALT was performed between the TIC and NSK ball screws for a total of 245 h, and the results are presented in Figure 14. The graph shows a rise in the temperature values at the 25-h mark for both ball screws design. The rise in temperature was significant in the case of TIC as compared to NSK. After the initial 50 h, the temperatures almost stabilized with some minor fluctuations resonating with the results obtained from a similar study [22]. NSK maintained a slightly higher average temperature than TIC over the majority of the test duration.

The ball screws were then thoroughly checked after the accelerated life test to evaluate their condition using different tests such as surface roughness, as shown in Figure 15. Where internal wear or degeneration was concluded to be −10% for ball screws from both companies. Ball size was also measured for both ball screws, and the values were found to be the same before and after the test.

The inspection showed no clear external defects as can be seen in Figure 16. Where each component was examined carefully. Thus, it was concluded that TIC and NSK exterior inspection was successful.

4. Discussion

This study examined the thermal and mechanical behavior of ball screws from two different manufacturers (TIC and NSK) used in machine tools, employing a combination of simulation and experimental methods. Initially, simulations were conducted to calculate temperatures and axial deformation through structural and thermal analysis. Additionally, their performance was assessed during multiple durability tests, in which both ball screws were subjected to extreme conditions over an extended period of time. Following the durability tests, further mechanical testing was carried out on the TIC ball screw to evaluate its properties, including thermal displacement due to reciprocating motion, torque fluctuation rate, and positioning repeatability precision. Overall, the following points have been drawn from this study:

• The TIC ball screw demonstrated superior thermal performance, with a maximum temperature of 32.6 °C in simulations, compared to 34 °C for the NSK. Similarly, the thermal deformation was also lower in TIC (119.34 µm) versus NSK (174 µm).
• Furthermore, durability testing, the ball screws were subjected to constant work, amounting to 245 h. In this test, although the thermal equilibrium was achieved almost at the same time, TIC had the average lower temperature compared to the NSK ball screw.
• In the quality verification testing of TIC ball screws, positioning repeatability showed a mean deviation of 4.99 μm, while maximum thermal displacement was 13.5 μm after 2000 cycles of reciprocating motion. The friction torque results were also satisfactory, with a maximum fluctuation rate of 19.9%.

Shortly, both types of ball screws successfully meet the industry standards for precision and durability machining. However, TIC ball screws showed a slight advantage in wear resistance and thermal stability, making them a potentially more reliable choice for long-term operation. Thus, this study contributes to the process optimization for precision manufacturing by letting consumers choose the correct product for their needs.

5. Future Recommendation

The following recommendations are proposed for future research and improvements:

• Further research can be done to optimize the material properties to enhance the thermal and mechanical properties of the ball screws.
• While the presented ANSYS simulation shows promising results, further refinements can be made in the simulation model where more complex boundary conditions can be used to simulate real-world operations.
• To better understand the tradeoffs between TIC and NSK ball screws, life cycle cost analysis should be done that will investigate factors such as maintenance, repair and replacement cost, etc.
• The effects of manufacturing processes such as heat treatment, surface coating etc. on ball screws can be discussed to strengthen the comparison.
• Advance monitoring techniques such as AI-driven monitoring and feedback system can be utilized to increase the efficiency and the quality control in ball screw manufacturing for process optimization.
• While the ALT spanned 245 h (~54% of theoretical life), it was sufficient to observe stabilization trends and early degradation. Future studies will explore extended testing (≥1000 h) to assess long-term durability.
• Expanding the study by testing additional ball screw models from various manufacturers to further improve the studied results.