High-speed Spindle Research Articles

Dynamic analysis on drilling of aluminum matrix composite of silicon carbide with cryogenically treated tools

Drilling of aluminum matrix composite of silicon carbide materials is analyzed using cryogenically treated drills under cryogenic conditions. Vibration acceleration, thrust force, geometrical aspects of drilled workpiece like hole quality, surface roughness, tribology properties of drill wear and chip morphology are evaluated at various drilling parameters such as spindle speed and feed rate. Experimental results showed that impact of spindle speed is considerably higher than impact of feed rate on vibration acceleration, whereas thrust force is influenced by spindle speed as well as feed rate. The maximum vibration acceleration obtained at the highest feed rate is 74.48 m/s2 and 81.34 m/s2 at the spindle speed of 3,000 rpm and 4,500 rpm. The hole diameter variation is 0.139 mm than original drill diameter and observed entry side hole diameter is slightly larger than that of exit side. Moderate spindle speed i.e., 3,000 rpm and 4,500 rpm produced better geometrical aspects of drilled workpiece and it is recommended for smooth drilling operation under cryogenic drilling condition. Adhesive wear is found to be prominent specially at the higher spindle speed. Smaller and smooth chips are observed at the lower spindle speed while short and curly shape chips are found at higher spindle speeds.

Experimental research on iron loss of high-speed spindle motor under variable frequency drive power supply

Experimental research on iron loss of high-speed spindle motor under variable frequency drive power supply

Development of a High-Speed Precision Ultrasonic-Assisted Spindle for Ultra-Precision Optical Mold Machining.

Ultrasonic vibration-assisted grinding is a critical method for machining ultra-hard optical molds. However, current ultrasonic-assisted grinding spindles, as essential foundational equipment, face limitations in maintaining ultra-high rotational speed, high precision, and a compact structure during ultrasonic operation. This study presents a novel ultra-precision ultrasonic-assisted high-speed aerostatic spindle for grinding ultra-hard optical molds, developed through theoretical calculations, FEM, and CFD simulations. The spindle features a simple and compact design (φ60 mm outer diameter × 194 mm length), operates at an ultrasonic frequency of 41.23 kHz, and is driven by an impulse turbine providing torque up to 50.4 N•mm, achieving speeds exceeding 40,000 r/min. Aerostatic bearings provide axial and radial load capacities of 89 N and 220 N, respectively. The results demonstrate that the proposed high-speed precision ultrasonic spindle exhibits both feasibility and potential for practical application.

Research on the nonlinear resonance response of the high-speed spindle system supported by preloaded ball bearings

Research on the nonlinear resonance response of the high-speed spindle system supported by preloaded ball bearings

Development Hybrid High-Speed Electro Pneumatic Spindles Drive Unit

Abstract The essence of the research is the search for geometric, material and technological limits of the new concept of spinning spindles. Considering the trend of introducing new generation electric drives into the segment of high-speed spinning spindles (over 120,000 rpm), it is necessary to map and describe the basic physical connections, to find the necessary dependencies and correlations of individual design parameters and their limits for the design of a new generation of spindles. Due to the design limitations of the original and years-used spindle drive concept with a belt and the requirement for the production and development of a new generation of spun fibers, it is necessary to expand the basic knowledge for the design of spindles of the new concept, the design of which will be based on the knowledge and dependencies obtained by measuring and examining the basic principles and determining parameters for the design of spindle structures of a new progressive concept.

Research on grinding parameter optimization based on adhesive semiconductor quartz disc

Abstract To study the influence of grinding parameters on the grinding force of semiconductor quartz disc based on the adhesive clamping method, an orthogonal experiment was designed to investigate the impact of grinding parameters on the grinding force. Based on the orthogonal test data, the influencing factors and parameter optimization of the grinding force are developed. The experimental results show that the order of influence of grinding parameters on the X-axis is feed speed > spindle speed > grinding depth, the sequence of effect on the grinding force in the Y-axis is grinding depth > feed speed > spindle speed, and the order of influence on the grinding force in Z-axis is grinding depth > spindle speed > feed speed. Therefore, using a higher spindle speed, a lower feed rate and a shallower grinding depth can play a role in reducing the grinding force. By improving the grinding parameters, the stability of quartz plate grinding based on adhesive technology is verified. It is found that adhesive is a more reliable clamping method, which ensures the processing quality of quartz plate and improves the working efficiency.

Characterization of influence of high spindle speeds on self-lubricating bearing system

Abstract This paper studies the influence of bearing speed under a self-lubricating system. In the early 20th century, specialized precision manufacturing companies were founded, further establishing ball bearings as a very valuable, high-quality, and easily accessible mechanical component. This study used a self-lubricating system to achieve constant temperature and precision control. The spindle speed was analysed and tested at three speeds under a fixed pre-loading of 13000 N and a fixed lubricating oil viscosity index of 15. The results showed the spindle speed increases, the heat generated increases, and internal component temperature changes also increase. When the spindle speed is 12,000 rpm, the temperature of the inner ring of the bearing increases and changes by 166.4 %, causing fatigue and scratch wear at the same time. Using a lubricating oil self-lubricating system can slow down the temperature rise rate of components. The operation system can quickly reach a stable state, reducing thermal deformation and temperature accuracy errors.

Study on the 2D equivalent nonlinear dynamics simulation model related to high speed precision bearing and spindle

The stiffness and contact stress of the bearing spindle system are the key factors affecting its machining accuracy and service life under the condition of high-speed service, which will be affected by different structural parameters and service conditions. It is essential to establish an efficient and accurate computational simulation model to understand the influence of complex factors on the nonlinear dynamic characteristics of the bearing spindle system. Firstly, in the paper, a 2D axisymmetric finite element model of the bearing, aims at the relationship between stiffness and contact stress of the bearing under high-speed service, has been built based on a classical dynamic analysis model and the reversed method of material parameters of equivalent rolling balls. Additionally, for the BT30 spindle, the 2D axisymmetric finite element model of the bearing spindle system also has been built and applied in mechanical analysis of spindle under different conditions of assembly and service, based on the bearing model. The results show that the axial force of bearings decreases as the rotational speed increases, and an augmentation in speed will result in a reduction in the axial stiffness of the BT30 spindle. In addition, the maximum contact stress exhibits a slight decline as the rotational speed increases. Furthermore, with an escalating preload, the stiffness and contact stress of the spindle undergo substantial increments, however, these parameters will cease to alter once a certain threshold is reached.

EXPERIMENTAL INVESTIGATION ON FREE VIBRATIONAL DAMPING AND DRILLING BEHAVIOR OF FLAX REINFORCED EPOXY COMPOSITES USING ADAPTIVE NEURO FUZZY INFERENCE SYSTEM

Flax reinforced epoxy (F-Ep) composites were prepared by the compression moulding technique, varying the fiber content (0, 25, 35 and 45 wt%). The free vibration test was performed on the neat epoxy and F-Ep composites to understand their dynamic characteristics, and results showed that natural frequency and damping factor of the F-Ep composites increased with an increase in the fiber content. The F-Ep composite (45F-Ep) that exhibited better damping was selected for performing the drilling operation. Factors such as spindle speed (rpm), feed rate (mm/min) and drill point angle (degree) were chosen as input parameters and the tabulated set of experiments were in accordance with Taguchi’s design of experiment. The response measured was thrust force and the obtained values were found in the range of 19.66 to 50.75 N. The minimum value of thrust force was achieved when the F-Ep composite was drilled at high spindle speed (3000 rpm), with a feed rate of 75 mm/min using the drill point angle of 118°. ANOVA analysis showed that the developed regression model was significant and thrust force was mainly influenced by the spindle speed. Mathematical models were developed for drilling F-Ep composite using response surface methodology (RSM) and adaptive neuro fuzzy inference system (ANFIS) and compared for their efficacy.

Design, analytical and computational analysis, and development of a high-precision CNC spindle for a vertical machining center

This research focuses on design, simulation and development of a high precision Computer Numerically Controlled (CNC) spindle for vertical machining center. High speed spindle is designed and analyzed under the varying load conditions. SolidWorks 2020 is used for designing of CNC spindle (based on ISO BT40 standards) and ANSYS Workbench 2020 is used for analysis. Moreover, analytical calculations for deformation are also done. Three different materials i.e. AISI 4340 steel, Grey cast iron, and Ti6Al4V alloy are chosen for the analysis. Effect of varying load on deformation and stress on CNC spindle is discussed. AISI 4340 steel showed better mechanical characteristics as compared to other materials. Moreover, the results showed that steel gives lesser values of deformation as compared to other materials, when applied under different load conditions. Although Grey cast iron can be economical and weight of the spindle can also be reduced but Grey Cast iron has greater value of deformation when load is applied. On the other hand, Ti6Al4V alloy specimen exhibited less stress as compared to other materials but mechanical properties in terms of modulus of elasticity are not that good as AISI 4340 steel. So, AISI 4340 steel could be a good option for spindle materials that require desired properties such as strong corrosion resistance, tensile strength, yield strength, and propagation. This will boost the accuracy and efficiency of spindle. Based on these results, high-precision CNC spindle was developed.

Digital twin–driven causal diagnosis mechanism for life health of high-speed spindle system

Digital twin–driven causal diagnosis mechanism for life health of high-speed spindle system

Thermal displacement prediction of high-speed electric spindles based on BWO-BiLSTM

To accurately, efficiently and stably predict the thermal displacement of the spindle, a prediction model based on the beluga whale algorithm (BWO) optimized bi-directional long and short-term memory neural network (BiLSTM) is introduced in this paper. Firstly, the thermal characterization and simulation analysis of the spindle are carried out, and the temperature and thermal displacement change characteristics of the spindle are obtained. Then the thermal deformation experiment of the spindle is carried out, and the temperature and displacement sensors are set up reasonably according to the temperature and thermal displacement change characteristics of the spindle, and the experimental data are collected and analyzed. The adaptive and globally convergent BWO is selected to optimize network parameters of BiLSTM, and the BWO-BiLSTM prediction model is constructed by learning the nonlinear correlation characteristics between spindle temperature and axial thermal displacement. The constructed BWO-BiLSTM prediction model is compared with other prediction models, and it is found through analysis that the prediction results output from the BWO-BiLSTM model have better accuracy and stability. The results of the study can provide a certain theoretical basis and technical support in predicting the spindle thermal displacement, which can help to promote the precision machining production of electric spindles.

A COMPARATIVE MODELING AND OPTIMIZATION OF SURFACE ROUGHNESS IN THE END MILLING OF Al 3003 SUBJECTED TO NON-EQUAL CHANNEL ANGULAR PRESSING (NECAP)

This paper highlights the surface roughness optimization of a specific material, Al 3003, which has been subjected to the non-equal channel angular pressing (NECAP) process. Considering spindle speed, feed rate, and depth of cut as input variables and surface roughness as an output variable, experiments have been conducted based on the L27 orthogonal array of the Taguchi method. Four prediction models, namely exponential and response surface methodology (RSM) as mathematical models, and artificial neural networks (ANNs) prediction models with different training algorithms (Bayesian Regularization (BR) and Levenberg–Marquardt (LM)), are proposed. Applying effectiveness and performance criteria, the prediction accuracy of the exponential model (90.35%), RSM (93.07%), BR (97.83%), and LM (97.54%) shows that all proposed prediction models are efficient enough. The ANN model trained with BR is found to be the best fit for predicting surface roughness. In order to optimize surface roughness, a newly introduced optimization method called the Intelligible-in-time Logics Algorithm (ILA) is employed. High spindle speed (1000[Formula: see text]rev/min), low feed rate (100[Formula: see text]mm/min) and depth of cut (0.5[Formula: see text]mm) have been the optimum cutting parameter combinations to obtain minimum surface roughness (0.4956[Formula: see text][Formula: see text]m). The results have been verified by confirmation tests and Particle Swarm Optimization (PSO) method. ILA and PSO predict the same optimum parameter combinations and minimum surface roughness, while ILA performs optimization in less time (114.4[Formula: see text]s), about 3.5 times faster than PSO. The paper’s findings strongly advocate the application of ILA in machining data optimization.

Experimental study on the ultrasonic assisted face turning residual stress

ABSTRACT The Experimental study investigates the impact of ultrasonic-assisted face turning (UAFT) on cutting forces, tensile residual stress, and surface topography. The primary objective is to identify optimal cutting parameters that yield a smoother surface finish while concurrently reducing cutting forces and tensile residual stress. The tests were conducted on a lathe machine equipped with ultrasonic assistance, using 1.7225 steel as the workpiece material. Various cutting parameters, including feed rate, spindle speed, and turning state, were varied. The results illuminate the significant efficacy of ultrasonic assisted face turn (UAFT) in improving surface topography, compared to conventional turning (CT). The optimal turning parameters for achieving the smoothest surface finish were determined to be a higher spindle speed and lower feed rate. Moreover, the introduction of ultrasonic vibration led to a substantial reduction in cutting forces, primarily attributable to the diminished attrition between the cutting tool insert and the work part. Overall, the experimental study demonstrates the effectiveness of ultrasonic-assisted face turning in enhancing surface topography, with an improvement of approximately 39%. Additionally, the study demonstrated a reduction in cutting forces by approximately 50% and a decrease in tensile residual stress by approximately 33.8%. These findings underscore the potential of ultrasonic vibration as a tool for optimizing cutting parameters to achieve desired surface finishes in machining applications.

Optimizing machining efficiency: a comprehensive study on PVD cathodic arc evaporation coated turning tool inserts with TiAlN/AlCrN multilayer coatings

The effectiveness of turning processes in manufacturing depends on the efficiency of cutting tool inserts. Coating these inserts is one common method that has been used to prolong their life span, reduce friction and increase wear resistance. The main purpose of the present study was to enhance the efficiency of turning tool inserts by exploring different combinations of coating substances such as TiAlN, AlCrN, and TiAlN/AlCrN. Cutting speed, feed rate, cutting depth and type of coating material were important input parameters for optimization. It was observed that tools with coatings like TiAIN and AlCrN had higher performance than those with single-layered ones. The use of multilayer coated inserts comprising TiAlN/AlCrN increased the hardness but reduced the wear thereby enhancing machining effectiveness. For Taguchi Grey Relation Analysis (GRA) optimization technique with L27 array for hardness and flank wear output parameters aimed at enhancement of input process parameters in turning operations. The coatings crystalline structure, phase composition and other crucial details for their performance were analyzed using Energy Dispersive (EDS) Spectroscopy and Scanning Electron (SEM) Microscopy techniques. The TiAlN/AlCrN coatings showed greater machinability than those with only TiAlN or AlCrN, even at high spindle speeds. The best processes were identified using the Taguchi and Grey relational optimization techniques. Some of these parameters include a speed of 600 m min−1, a feed rate of 0.10 mm rev−1, a depth of 1.5 mm, and a TiAlN/AlCrN coating. This meant that the hardness was at 3772 HV while flank wear is 6.45 mm for optimum parameters among others obtained from experiments. The Grey relation analysis results demonstrated significant improvement in grade indicating the good performance of selected parameters. Various relationships can be displayed using contour plots which are usually visual representation between several factors in an experiment such as hardness and wear resistance which is shown by multilayer coating compared to single-layer coatings.

High-speed tooth-coil permanent magnet synchronous machine for motorized spindle application

The slender shape of the driving machine leads to a low rigidity and large axial thermal elongation of the motorized spindle, which deteriorates the machining precision. To solve these problems and pursue a more compact size, this paper investigates the feasibility of using a tooth-coil permanent magnet synchronous machine in a high-speed spindle, replacing the original motor that has the conventional distributed winding. Comprehensive performance and behavior of machines with distributed and tooth-coil windings are comparatively analyzed, in terms of the essential torque ripples, winding inductances, electromagnetic losses, rotor integrity, and heat dissipation of the spindle. Thorough numerical simulation results indicate that the newly designed tooth-coil winding solution shows significant advantages over the original design, regarding high rotor rigidity, low torque ripples, reduced electromagnetic losses, and reduced shaft thermal elongation. Prototypes and test setups for the high-speed tooth-coil machine are built, where preliminary measurements are carried out to validate the analysis results and system design.

Coupling Study on Quasi-Static and Mixed Thermal Elastohydrodynamic Lubrication Behavior of Precision High-Speed Machine Spindle Bearing with Spinning

In this work, a modified numerical algorithm that couples the quasi-static theory with the mixed thermal elastohydrodynamic lubrication (mixed-TEHL) model is proposed to examine the mechanical properties and lubrication performance of the spindle bearing that is used in a high-speed machine tool with spinning. The non-Newtonian fluid characteristics of the lubricant and the non-Gaussian surface roughness are also considered. Moreover, the mechanical properties and lubrication state of the bearing are examined in various service environments. The results indicate that the temperature reduces the lubrication efficiency, which in turn exerts a significant impact on the mechanical properties. The lubrication that either behaves in the manner of Newtonian or non-Newtonian fluid has a relatively negligible influence on the bearing working state, while the non-Gaussian surface roughness significantly alters the oil film thickness and temperature. Calculations with different operating conditions demonstrate that the operating parameters (i.e., axial load, rotation speed) will directly affect the performance of the bearings via the changes in the oil film thickness and the temperature.

Non-invasive rotor temperature detection of magnetically levitated turbo molecular pump based on high-frequency inductance

The rotor temperature has a significant effect on the reliable operation of the magnetically levitated turbo molecular pump (MLTMP). Therefore, it is crucial to monitor the rotor temperature during the operation of the MLTMP to prevent irreversible demagnetization of the permanent magnet and improve production efficiency. However, direct measurement of rotor temperature is a challenge due to the complexity of installing a temperature sensor on the high speed spindle. This paper presents a non-intrusive method for detecting rotor temperature based on high-frequency(HF) inductance estimation. On this basis, a novel method is proposed that injects a HF rotating voltage into the stationary coordinate frame and introduces synchronous demodulation to achieve accurate estimation of the HF inductance. Finally, the experimental results conducted on the MLTMP test bench indicate that the proposed method can effectively detect the rotor temperature, and the temperature error is within 3 ∘C.

Evaluation of the performance characteristics of aerostatic bearing with porous alumina (Al2O3) membrane using theoretical and experimental methods

Instruments with high levels of precision commonly use aerostatic bearings. Moreover, the use of porous (Al2O3 membrane) material validates that the pressure is spread uniformly throughout the air film region. The impression of applied load on the thickness of the air film of the aerostatic bearings was evaluated using a certain experimental technique. As the applied load rises, the thickness of the air film expands, and as the compressive stress rises, it contracts. The theoretical model parameters were set using the experimental stipulations. It was discovered that the theoretical model and the experimental data were consistent. The pressure gradient induced in the air film and the air bearings’ capacity for carrying loads were calculated using a theoretical simulation. The results of theoretical modeling and experimental comparison of the different characteristics of porous (Al2O3 membrane) aerostatic bearings based on stiffness and load-carrying capacity are graphically illustrated in this study. Porous aerostatic bearings with Al2O3 membranes have a number of potential applications, including high-speed spindles, precision instruments, microelectromechanical systems, vacuum pumps, cryogenic applications, etc.

Optimal design of stator slot with semi-closed type to maximize magnetic flux connection and reduce iron leakage in high-speed spindle drives

A novel approach was devised to optimize the stator slot semi-closed type in order improve the magnetic flux connection and minimize iron leakage in high-speed spindle drives. The concept was executed through a combination of response surface approach including the technique of finite element analysis. The primary objective of this investigation would be to provide an engineering approach which improves the functionality of stator criteria, including the stator slot geometry, coil turn per slot, and wire size. The purpose is to achieve higher flux connection and minimize iron leakage. This study presents an enhanced analytical approach that incorporates the analysis of stator flux connection, finite element calculation of flux connection, and iron leakage analysis of stator variables. The results are analyzed through the utilization of finite element computation, and their accuracy is verified through experimental measurements. The findings suggest the ideal design yields increased magnetic flux connection and reduced iron leakage in comparison to the industrial layout. The precision provided by the suggested model is confirmed through the comparison of the simulation and experimental information. In general, the percentage of errors is estimated to be around 7%.