Cylindrical Grinding Research Articles

Simultaneous cutting and grinding of micropins using cylindrical microtools

Decreasing cutting force is always crucial in cutting processes. One method to achieve this is by minimizing tool wear, for which rotary cutting is a highly effective technique. The use of a cylindrical tool offers the additional benefit of easy tool fabrication, which is especially advantageous for a microtool capable of machining micropins. However, there have been no reported studies on rotary cutting using a cylindrical microtool. It should be noted that if a microtool is fabricated by electrical discharge machining, it is expected to engage in cylindrical grinding as well. This suggests that both rotary cutting and cylindrical grinding can be carried out simultaneously; however, there have also been no reported studies on simultaneous cutting and grinding. Therefore, the present study investigated whether this machining method can perform micropin machining, if it actually involves both cutting and grinding actions, and whether the combination of these actions enhances material removal capability. In turning and grinding experiments, where only one of the tool and workpiece was rotated, both actions were observed. Furthermore, it was confirmed that micropin machining can be performed by rotating both the tool and workpiece, resulting in a decrease in machining force to approximately one-quarter to one-half compared to that of turning. This indicates that simultaneous cutting and grinding was carried out, and the overlap of their actions enhanced material removal capability. In addition, the relationship between the machining conditions and machining force was investigated. At a small depth of cut, a tool with smaller surface roughness exhibited lower machining force than a tool with larger roughness, and the opposite was true at a large depth of cut. Finally, an ultrasmall-diameter micropin with a diameter less than 3 μm was successfully machined using conditions capable of reducing machining force.

Optimizing Cylindrical Grinding Proficiency and Surface Finish for EN24 Steel Alloy with the Use of Taguchi Analysis and Artificial Neural Network

Grinding is a material removal procedure used at the end of manufacturing to obtain high dimensional precision and a desirable surface polish. External cylindrical grinding is a type of grinding procedure that used to grind cylindrical things such as engine shafts, connecting rods, spindles, and axles. This study examines how control settings affect response parameters using EN24 alloy steel on a cylindrical grinding machine. Response parameters are material removal rate (MRR) and surface roughness (Ra), whereas control parameters are workpiece speed (v), feed rate (f), and depth of cut (d). Taguchi DOE is employed with L16 orthogonal array to optimize control parameter levels, followed by cylindrical grinding tests.An artificial neural network (ANN) model was created to validate and predict cylindrical grinding reaction parameters. To train the network, experimental data was used, and ANN predictions were compared to real data. Data collection has also completed.In the purposed work minimum Ra is 0.52 µm and maximum MRR is 0.6588 g/sec found and results indicate that feed rate and workpiece speed are the most dominating parameters of cylindrical grinding. The experimental results can be employed by various manufacturing and industrial firms and they can select suitable combinations of input parameters for desired Ra and MRR

Modeling and experimental study of the force and surface topography in cylindrical grinding of GH4169

Modeling and experimental study of the force and surface topography in cylindrical grinding of GH4169

Transforming Old to New

A machine overhaul by cylindrical grinding machine manufacturer Studer is helping to breath new life into old machines by upgrading their efficiency, performance and precision

Research on Cloud-Edge-Device Collaborative Intelligent Monitoring System of Grinding Wheel Wear State for High-Speed Cylindrical Grinding of Bearing Rings

Aiming at the problems of grinding wheel wear during high-speed cylindrical grinding, communication delays, and slow response during data acquisition, processing, and system operation, an intelligent online monitoring technology frame for CNC manufacturing units is proposed, incorporating a real-time-perception grinding mechanism and a cloud-edge device. Based on the grinding data and grinding wheel wear mechanism, a monitoring model using multi-sensor information fusion is constructed to assess the grinding wheel wear state. In addition, edge data acquisition and online monitoring software have been developed to improve the speed of data transmission and processing. Finally, based on the proposed framework, a cloud-edge device collaborative intelligent monitoring system for assessing grinding wheel wear during high-speed cylindrical grinding of bearing rings is constructed. It improves the grinding quality and efficiency, reduces the grinding cost, and incorporates remote control functionality.

Impact of morphological and mechanical components on inconel 625 grinding using common cylindrical grinding wheels

This study used a grinding technique based on Gas Tungsten Arc Welding (GTAW) to create walls composed of Inconel 625 alloy. Mechanical and microstructural (MM) adjustments are structural and mechanical alterations that take place during the additive manufacturing process of Inconel 625 grinding. A thorough examination of the modifications made to the nickel superalloy Inconel 625's (I-625) microstructure was conducted during the grinding process. A circular weave and a stringer bead design were used to construct the wall. Tensile properties and microstructural analyses were assessed for each wall. Using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS), the fracture zones of the tensile specimens were examined. The microstructure is mostly composed of equiaxed dendrites, although a unique combination of discontinuous and continuous cellular dendrites can be observed along the cross-section. In tensile testing, circular woven walls performed better than stringer bead walls. The EDS and AFM results show that Ni and Cr make up the majority of the fracture zone, with traces of Nb and Mo. Because there are no lave phases, the fracture mode is ductile. The elemental mapping, which shows the homogenous dispersion of Ni and Cr inside the fracture zone, provides additional evidence in favor of the ductile failure mode. The UTS of the time-consuming TS samples is somewhat higher and exhibits a steadily rising bias in comparison to the specimens with quick TS. The highest level of the UTS sample is 10 %.

Establishment and verification of a prediction model for the grinding force and residual stress in cylindrical grinding of 18CrNiMo7-6 alloy steel

Establishment and verification of a prediction model for the grinding force and residual stress in cylindrical grinding of 18CrNiMo7-6 alloy steel

A green and precision compound machining method for glass micro components – Ultrasonic assisted electrochemical discharge grinding with multi-hole tube electrode

Glass is a widely used material in key fields such as Micro-Electro-Mechanical Systems (MEMS) due to its excellent properties. The existing non-traditional glass machining methods have problems such as high pollution, difficult operation, and poor sustainability, this article utilizes the effective combination of electrochemical discharge machining and grinding (named electrochemical discharge grinding, ECDG), by using NaHCO3 solution as electrolyte to achieve green machining. Utilizing ultrasonic vibration and multi-hole tube electrode to achieve precise and stable machining. Modeling and simulation analysis were conducted on the material removal rate and grinding force during the machining process, which profoundly revealed the joint improvement mechanism of spark discharge and ultrasonic vibration on grinding quality. First, a single factor experiment was used to preliminarily determine the machining threshold. Second, the Plackett-Burman experiment was used to screen key machining parameters. Then, Box-Behnken experiment was conducted on key machining parameters, and multi-objective and multi-factor optimization was performed to obtain the optimal combination of machining parameters. Compared with normal ECDG with cylindrical grinding electrode, the overcut is reduced by 8.3 %, the edge damage is reduced by 17.5 % and the surface roughness value is reduced by 70.6 %. Finally, by using the optimized combination of machining parameters, high-quality and stable machining of typical microchannel structures was achieved. The milling depth of the microchannel is 400 µm. The machining width is 1175 ± 5 µm. The surface roughness of the measurement area is 0.375 µm. The green, high-quality and stable machining of micro glass micro components further demonstrates the potential application of this compound technology.

Special Tools in Spain

The Spanish TEMSA Metallurgical Group is a leading manufacturer of special tools for cold forming. The company operates cylindrical grinding machines from Studer in its production

Advancements and Challenges in Robot-Assisted Bone Processing in Neurosurgical Procedures.

Practical applications of nerve decompression using neurosurgical robots remain unexplored. Our ongoing research and development initiatives, utilizing industrial robots, aim to establish a secure and efficient neurosurgical robotic system. The principal objective of this study was to automate bone grinding, which is a pivotal component of neurosurgical procedures. To achieve this goal, we integrated an endoscope system into a manipulator and conducted precision bone machining using a neurosurgical drill, recording the grinding resistance values across 3 axes. Our study encompassed 2 core tasks: linear grinding, such as laminectomy, and cylindrical grinding, such as foraminotomy, with each task yielding unique measurement data. In linear grinding, we observed a proportional increase in grinding resistance values in the machining direction with acceleration. This observation suggests that 3-axis resistance measurements are a valuable tool for gauging and predicting deep cortical penetration. However, problems occurred in cylindrical grinding, and a significant error of 10% was detected. The analysis revealed that multiple factors, including the tool tip efficiency, machining speed, teaching methods, and deflection in the robot arm and jig joints, contributed to this error. We successfully measured the resistance exerted on the tool tip during bone machining with a robotic arm across 3 axes. The resistance ranged from 3 to 8 Nm, with the measurement conducted at a processing speed approximately twice that of manual surgery performed by a surgeon. During the simulation of foraminotomy under endoscopic grinding conditions, we encountered a -10% error margin.

Effect of Acoustic Emission Sensor Location on the Detection of Grinding Wheel Deterioration in Cylindrical Grinding

The acoustic emission (AE) technique is an effective method for monitoring grinding wheels, and numerous studies have been published on applying an AE to monitor grinding wheels. However, there are few studies on the effect of the location of the AE sensor in stably acquiring the AE signals generated during deterioration in cylindrical grinding wheels. In this study, we propose a stable method for detecting the deterioration of a cubic boron nitride (cBN) grinding wheel during cylindrical grinding using AE. We compared the AE signals acquired during grinding from an AE sensor located on the hydrostatic bearing, which supports the grinding wheel shaft, with those from the tailstock spindle. Although positioning the AE sensor on the hydrostatic bearing was found to reduce the AE signal intensity, the AE signal variations were smaller at the same grinding position, and the effect of the grinding position was less than that for the tailstock spindle. Moreover, positioning an AE sensor on the hydrostatic bearing is considered to provide the characteristics of AE signals specifically focused on the changes in cBN on the grinding wheel surface allowing the surface roughness of the workpiece to be estimated during grinding.

Application of TOPSIS Method for Determination of the Best Dressing Parameters in Internal Cylindrical Grinding

Application of TOPSIS Method for Determination of the Best Dressing Parameters in Internal Cylindrical Grinding

Towards developing a control of grinding processes using a combination of grinding power evaluation and Barkhausen noise analysis

After grinding of hardened workpieces, especially in case of safety-relevant components, usually non-destructive testing is carried out to detect thermo-mechanical damages in the surface layer. In-process detection methods allow a fast reaction to negative changes before producing a large amount of rejects and open the possibility to save additional time for post-process inspection. However, these are not industrially used yet, since boundary conditions and application limits are not defined so far. This study shows the potential of a grinding process control based on a soft sensor combining a thermal limit in a Pc′′\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${P}_{c}^{{\\prime}{\\prime}}$$\\end{document}− Δt-diagram and magnetic Barkhausen noise analysis applied in-situ during grinding (BN). The specific grinding power Pc′′\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${P}_{c}^{{\\prime}{\\prime}}$$\\end{document} in dependence of the contact time Δt allows to identify/avoid grinding burn starting from light tempering zones. Furthermore, the BN is well suited for the detection of detrimental residual stress changes (tensile) occurring even before tempering zones are generated. The developed process control based on this combination optimizes the process parameters to prevent negative thermo-mechanical surface changes while keeping the productivity of the process as high as possible. The applicability is demonstrated for external cylindrical and non-circular grinding processes. Due to the radius varying over the workpiece circumference, the latter ones require special demands on signal evaluation, resolution and control speed.

Rotary dressing and cylindrical grinding simulation for lead pattern prediction

A kinematic model of rotary dressing - cylindrical grinding for lead pattern prediction is presented. Analysis of dressing and grinding parameters, dressing forces, and wheel imbalance effects has been conducted, providing a comprehensive look at the interrelationships between them and the resulting lead pattern. For model validation, a series of experimental tests has been performed, where workpiece and simulation lead has been characterized according to MBN 31,007–7 standard. Results emphasize the significance of modelling and translate it into a useful tool for selecting optimal dressing and grinding parameters for achieving specific surface qualities where lead is minimised or eliminated.

Detection of thermo-mechanical damages by in-process Barkhausen Noise Analysis combined with Grinding Power Evaluation

Grinding of workpieces from hardened steel, especially in case of safety relevant components, usually requires a reliable method for the detection of thermo-mechanical surface damages. Compared to the common post-process methods, in-process detection promises saving of detection time and, particularly, a fast reaction to negative influences on the surface integrity. The present work shows the suitability of magnetic Barkhausen noise (BN) for the in-process detection of thermo-mechanically influenced regions during an outer diameter cylindrical grinding process. Different from other non-destructive inspection methods, BN allows the detection of changes of the residual stress state even before the occurrence of visible tempering zones. However, in case of pronounced tempering or rehardening zones, a single BN value does not enable an unambiguous statement about the surface state. Therefore, additionally the specific grinding power Pc” in dependence of the contact time Δt is considered, which allows to exclude grinding burn starting from light tempering zones. A particular focus of this study is the BN analysis during grinding with different types of grinding wheels.

Research on the grinding rounding mechanism and law of the cylindrical grinding system supported all by hydrostatic spindles

The maximum achievable journal roundness accuracy range by the conventional “Rolling bearing supported spindle and fixed center clamping” grinding solution is about 0.2–0.5 μm, which barricades the grinding roundness improvement. To further improve the grinding roundness, this study proposes a novel “Fully hydrostatic supported spindle and movable center clamping” grinding solution, which adopts hydrostatic supported grinding wheel spindle, and hydrostatic supported movable clamping centers. Firstly, based on the interaction between wheel and workpiece, a coupling material removal deformation compatibility model is built, and the rounding process of external cylindrical grinding is quantitatively simulated. Secondly, a fully hydrostatic supported grinding system is developed and tested. The optimal roundness error in the experiment reached 0.12 μm, the maximum relative error between the simulated results and the measured average results is 18.5 %, which validates the proposed solution and the algorithm. Thirdly, from the perspective of grinding parameters, the grinding rounding law of the system is studied. Finally, the proposed grinding solution is compared with the conventional grinding solution, the novel grinding solution has better grinding efficiency and grinding roundness. The proposed grinding solution may provide a new path for grinding accuracy improvement.

An intelligent recommender system for tool selection in conventional machining

ABSTRACT Cutting tool manufacturers face a tough challenge in developing custom solutions for specific customer requirements. Several trials are required, encompassing the selection of materials, tool configuration parameters, manufacturing of tools and testing under target conditions to arrive at an acceptable solution. In this work, the authors present a recommender system that utilizes a hierarchical deep learning-based machine learning model, handcrafted using domain knowledge, to predict top N tool configurations for a given target requirement with a probability score. The authors also discuss methods for data augmentation to deal with limited data as well as a probabilistic approach to predict the top N tool configurations from the trained models. The proposed system is applied to a case of centerless cylindrical grinding wheel selection problem. The outcomes indicate an overall accuracy of 92.4% for single best-fit specification, with 100% within the top five recommendations for past designs. Some of the alternatives proposed by the model are observed to be potentially superior to what was chosen earlier by experts. Without the selection hierarchy, a deep learning model achieved a single best-fit accuracy of 83.5% and the probabilistic model achieved a top-five recommendation accuracy of 89.8%, highlighting the merit of the hierarchical approach.

Chatter reliability of high speed cylindrical grinding with uncertain parameters

Cylindrical grinding is commonly used as the final process of machining, but its quality and efficiency are often limited by chatter phenomenon. Many research show that the result from conventional chatter analysis by using the deterministic parameters is not consistent with the practical working condition and the chatter reliability prediction in high speed cylindrical grinding with uncertain parameters is studied in this paper. The dynamic model of the cylindrical grinding system is established, and uncertain parameters such as mass, stiffness and damping coefficient are introduced, and the stability lobe diagrams with uncertain parameters were obtained. The reliability model of the grinding system was established, and the reliability was solved by using the Monte Carlo simulation method, the improved first-order second-moment method and the second-order second-moment method, respectively. Then, the chatter-free reliability of the system was predicted by using the reliability lobe diagram. The accuracy of the grinding reliability prediction results is verified by the experiment results. Furthermore, the Monte Carlo sensitivity analysis method is used to study the influence of random parameters on the grinding system, and the results show that the variation of modal mass has the greatest influence on the reliability of the grinding system.

Ultra-precision grinding of monocrystalline silicon cylindrical mirror

As one of the important functional components in the optical diagnosis system, the processing accuracy of monocrystalline silicon cylindrical mirror directly affects the overall performance of the entire experimental device. In order to obtain high-precision monocrystalline silicon cylindrical optical elements, the coordinate transfer function models of the diamond wheel in the cylindrical surface parallel grinding process were established, and the forming process scheme was proposed based on the wheel dressing precision and element grinding precision. At the end, the experiment for a monocrystalline silicon cylindrical mirror with size of 440mm × 50mm was carried out. The PV value of form error after grinding was about 2.7μm, which proved the correctness of the transfer function and the forming process scheme of monocrystalline silicon cylindrical optical element.

Stability Analysis and Nonlinear Chatter Prediction for Grinding a Slender Cylindrical Part

A cylindrical plunge grinding process was modeled to investigate nonlinear regenerative chatter vibration. The rotating workpiece was a slender Euler–Bernoulli beam, and the grinding wheel was a rigid body moving towards the workpiece at a very low feed speed. A numerical method was proposed to provide the critical boundaries for chatter-free grinding. It was demonstrated that the intersection set surrounded by these critical boundaries was the chatter-free region for the considered parameters. When these parameters were outside of the chatter-free region, the stable grinding process underwent a supercritical Hopf bifurcation, resulting in the loss of the chatter-free behavior and the emergence of periodic chatter motions. Then, the periodic motions of both the grinding wheel and the workpiece were predicted analytically using the method of multiple scales, showing the effect of the regenerative force on the grinding process. We demonstrated that the analytical prediction was valid since it agreed with the numerical simulation. The results showed that there exist three kinds of nonlinear chatter motion, with different amplitudes and mode frequencies.