Papers by Keyword: Profile Grinding

Abstract: In order to improve the prediction accuracy of the grinding surface roughness, this paper presents a prediction algorithm based on Least Squares Support Vector Machine with Particle Swarm Optimization (PSO-LS SVM). Chose the radial basis function as the kernel function of this new algorithm in where the regularization parameter and kernel function parameter of LS SVM were optimized by PSO, then the grinding surface roughness prediction model was established with the parameters optimized before. Through experimental analysis, it can be realized that compared to the conventional prediction methods, the prediction results of the proposed algorithm are closer to the actual roughness and the relative errors are smaller. As a result, the proposed algorithm is more acceptable.

Abstract: The localized wear on grinding wheel edges is a common phenomenon on profile grinding since the abrasive grains are less attached to the bond. The grinding wheel wear depends heavily on the process parameters, workpiece and wheel composition, causing changes on the process and profile deviation behaviors. In order to cope with these uncertainties, many natural and synthetic materials have been used in different grinding processes. However, the influence of mixed compositions of different types of abrasive grains on external cylindrical grinding is not well known. In order to assess this relation, a methodology procedure was developed providing an overview of the cinematic edges behavior on a progressive wheel wear. The methodology procedure is based on the acoustic emission technology, using a transducer with a 50 μm radius diamond tip. The tip, when in contact with a rotating grinding wheel, enables the evaluation of the cinematic cutting edges. The abrasive grain density was evaluated for different grinding wheel compositions and specific wear removal values. Furthermore, these results were compared to the profile deviation observed on the same tool, allowing the assessment of the influence of different microcrystalline corundum grains on the overall grinding wheel wear behavior.

Abstract: Based on the analysis of the piston engine camshaft common failure mode, combining the mechanical analysis and risk management means,the feasibility of its repair was much discussed, the repair technique are studied, and proved its correctness and effectiveness.

Abstract: Generally in the grinding of modern aviation materials such as nickel-based superalloys, problems frequently occur in terms of burr formation, profile loss of the wheel, high heat generation in the contact zone, high grinding forces as well as low process reliability. A recent and promising method to overcome these technological constraints is the use of ultrasonic assistance, where high-frequency and low amplitude vibrations are superimposed on the movement of the workpiece. This paper presents the design of an ultrasonically vibrated block sonotrode and the experimental investigation of ultrasonically assisted profile grinding of Inconel 718. The profile wear, radial wear of the wheel, grinding forces and surface roughness by ultrasonic-assisted and conventional profile grinding were measured and compared. The obtained results show that the application of ultrasonic vibration can decrease the radial wear of the wheel, profile wear, grinding forces and surface roughness considerably.

Abstract: In this paper, a precise profile ELID grinding with Electrical Discharge Truing(EDT) has been introduced, and some experiments for efficient and precision EDT process with cast iron-bonded diamond wheel have been carried out with four types of medium: mist, water, pressure air, air, furthermore some machining parameters e.g. electric current, electric voltage have been discussed in detail. For analyzing of the accuracy of EDT process with cast-iron bonded diamond wheel, a profile measurement method with software of MATLAB was used for analyzing of the profiles of cast-iron-bonded diamond wheel and electrode. It can be found that the electrode’s profile can be kept with the consistent designed profile, and the grinding wheel with the designed profile has been got by the appropriate EDT process. Therefore the higher efficiency and precision EDT process can be achieved by the appropriate EDT machining parameters.

Abstract: Spindle thermal deformation is the main error source of many precision profile grinders. In this paper, the relationship between spindle temperature and either radial or axial thermal deformation is studied based on experiments. The placement and amount of temperature sensors are optimized. Then a kind of thermal error modeling method based on support vector machine is presented and applied in the modeling of thermal error of profile grinding. The result shows the model is robust and the on-line accurate prediction of grinding thermal error is realized based on monitoring of temperature rise of spindle. Finally, the error compensation strategy is discussed for further application of thermal error modeling.