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The article offers the force and geometry analysis of the stone block–diamond wire saw system. The friction force of the diamond wire saw in the block is determined at the parabolic adjustment of the wire sawing trajectory. The curves of the sawing force and horizontal coordinates of the blocks are plotted at different values of the parabola focus point. The actual sawing trajectories in monoliths and blocks are described. The load increase factor at the beginning of work is obtained. Using the procedure of the actual sawing trajectory, the strength analysis of the diamond segments of the diamond wire sawing machine is performed, and the stress diagrams in the diamond segments with a sharp and rounded edge are constructed. The maximal stresses in the diamond segment with the rounded edge are plotted as function of the rounding radius.

In this study, a multi-tooth sawing force prediction model is proposed for the stainless steel sawing process, combined with the classical cutting theory of band saw and the introduction of tooth equivalent cutting width. Through the numerical simulation of sawing process and sensitivity analysis method, the influence law of feed speed and cutting speed on cutting force was analyzed. A sawing process parameter optimization design model with sawing force and sawing efficiency as the optimization objectives was established and solved by multi-objective optimization algorithm to determine the optimal combination of coordinated sawing force and sawing efficiency process parameters. The stainless steel sawing test results show that the multi-tooth sawing force prediction model and the experimental results match; the maximum error does not exceed 6%, making it better to achieve the prediction of sawing force in high-frequency strong impact conditions. With the optimized design of process parameters, the sawing force decreased by a maximum 20.43%, and the sawing efficiency increased by a maximum 54.72%. This study provides a reference for metal sawing force prediction and process parameter optimization, and also offers theoretical guidance for developing high-end sawing equipment.

The sawmill industry process a significant quantity of the logs into lumber for wood industry in Ethiopia. The cost of raw materials have a significant role in the wood industry. Therefore, it is critical to pay attention to the proper log sawing method, which optimize the sawing process and increase the lumber recovery rate and lumber grading. Eucalyptus, is currently gaining significance in wood industry for lumber production and for construction purposes in Ethiopia. In the present study, Eucalyptus globulus logs were processed into lumber using plain, quarter and radial sawing methods. In the plain sawing, the results showed that a total 6.77 m3 of lumber were produced from log categories 1, 2, 3, and 4. In the quarter sawing, a total 5.07 m3 of lumber were produced from log categories 1, 2, 3, and 4. While in the radial (rift) sawing, a total 4.76 m3 of lumber were produced from log categories 1, 2, 3, and 4. Overall, the lumber recovery rate 49% were recorded. There was a highly significant difference (P ≤ 0.001) in the sawing methods. Visual grading is based on a visual inspection of the each piece of the lumber and the judgment of the grader. In the present study, lumber grade yield was classified into percent’s of 83–100%, 66–82%, 50–65%, and below 50%, and lumber grade names were No. 1C and better, No. 2AC, No. 3AC, and No. 4 (economy), respectively. The major structural factors that determined in the sawn wood grade were the size and frequency of the defects on the lumber because log characteristics would appear in a given piece of the lumber and affects the grading of sawn wood or appearance. The study results shows that the logs with a lower grade or more defects resulted in lower lumber recovery and grade yield. In conclusion, the plain sawing method is the most commonly used for E. globulus lumber production in the sawmill industry. Apparently, plain sawing is a least wasteful, most economically used for sawing the logs, and producing the widest lumber than others. However, the lumber produced using this method are more liable to warp, split, shrinkage and distortion than those of other methods. Quarter sawing has the benefits of reducing warping, shrinking, twisting, and cupping, checking and splitting lumber rather than those which are plain sawn. This is the best technique for E. globulus lumber production, especially more appropriate for sawing a large diameter of the logs. Lastly, radial sawing has the highest wood waste, the time consuming and expensive, and the strongest sawing technique for E. globulus lumber production. This investigation confirms that the quarter sawing method is suitable for producing high quality lumber from E. globulus. The enhanced lumber recovery and grade yield increase the profitability, energy efficiency, optimum use of the resources, manage wood waste (e.g., recycling and prevention), and mitigate climate change impacts effectively for green economic development and industrial transformation.

Using the RadSawSim simulator for radial sawing, a simulation of the radial sawing technique was used to saw Pedunculata oak (Quercus robur L.) logs. Simulation was implemented with a view to producing as many radially sawn boards as possible and took into account the influences of increasing volume yield, lumber value yield, and log-value yield. The methods that were analyzed were live sawing and radial sawing of third sections, fourth sections, fifth sections, and sixth sections of the log. Live sawing achieved the best results of volume yield during simulation, which was followed by radial sawing into the third, fourth, fifth, and sixth sections. The difference in volume yield with live sawing compared to the radial-sawing method is very large for logs up to a diameter of 45 cm. It becomes smaller when the log diameter is greater than 45 cm. A comparison of the radial method shows that the share of radially sawn boards and lumber value yield increased when the number of log sections during sawing simulation increased. If log-value yield is assumed to be the main criterion, and given the conditions used in this simulation, there is no justified reason to saw logs using the radial technique when the diameter is less than 45 cm. The live sawing technique is more efficient for these diameters of logs, and, therefore, the radial sawing technique is more efficient for logs with a diameter greater than 45 cm.

In the diamond wire sawing (DWS), the wire bow provides cutting force, reflecting the cutting ability and the saw wire cutting state, which is one of the important issues that need to be paid attention to in industrial production. Selecting the appropriate wire bow in the sawing process can not only improve the surface quality of the wafers, but also reduce the probability of breakage. Therefore, the prediction of the wire bow is of great significance for improving the yield of the wafers and reducing the wear of the diamond wire. In this paper, the force analysis of the wire bow formed by the sawing process is carried out, and the relationship between the cutting force and the material removal rate is obtained from the microscopic abrasive scratching process. The wire bow prediction model of diamond wire sawing based on process parameters is founded, and the accuracy of the model is verified by experiments. The established model is used to analyze the influence of process parameters on the wire bow in the current solar photovoltaic silicon cell substrate cutting, which provides guiding significance for diamond wire sawing production.

Diamond wire sawing has gradually applied as the dominant way of silicon sawing in the photovoltaic and semiconductor industry. In this paper, a model of stiffness of wire web was established, and the corresponding test measure, process, and evaluation standard were proposed. Lack of stiffness of wire web could easily cause wire bow and further reduce the machining accuracy during diamond wire sawing. And the machining accuracy due to wire bow was analyzed. The special significance of this study is considered the stiffness of wire web to be the key index of multi-wire sawing performance. Through this method, the wire bow and the lack of cutting accuracy can be reasonably evaluated. As a result, wire lag and wire bow due to the loss of the stiffness of wire web could be minimized, as well as its influence on machining accuracy. Static stiffness matrices of wire web were presented to analyze the influence of the feed position and the number of wires forming the wire web on the stiffness of wire web. Moreover, a FEM model was established to find the influence factors such as wheel span, wheel diamond, and preset tension on the stiffness of wire web. Graphical abstract

Sawing by circular saw blades is predominant in the mechanized treatment of natural stone. The predictive sawing force is crucial for optimizing, controlling, and monitoring the sawing process. In this work, a novel model for predicting sawing force, which is based on the distribution of the undeformed chip thickness at the sawing contact arc, was proposed. Based on the analysis of the undeformed chip geometry of the circular saw blade, the segment surface was divided into the front end and rear end according to the contact pattern between the segments and granite, and the models of the maximum undeformed chip thickness of diamond particles on the front end and rear end were established. Results showed that the new proposed force model fully considered the distribution of undeformed chips compared with the current model. The novel model has higher prediction accuracy, the mean maximum absolute error is within 3.77%, and the maximum absolute error is within 7.83%. Through theoretical analysis, the ratio of the maximum undeformed chip thickness of the front segment to the rear segment is 1.67, which can fully explain the wear non-uniformity of the segment. The proposed model is of great significance to the optimization of the saw blade structure and process parameters.

Thin lamellae, corresponding to the layer components of structural glued members, i.e., 2-ply or 3-ply glued flooring, can be manufactured in re-sawing operations of kiln-dried wood blocks or in wet technologies, which currently seem to be more common because of the shorter drying time. The re-sawing process in wet technology is conducted on dedicated thin-cutting band sawing machines with stellite-tipped band saws. The goal of this research was to demonstrate the capacity of surface production (m2/ tool life) of visible layers of oak engineered flooring composites in a function of both a new band saw and a re-sharpened band saw blade. Additionally, the state of teeth of each band saw blade was examined at the end of the tool life. A series of cutting tests were performed in sawmill production conditions. The conducted tests revealed that a three times higher capacity of surface production was obtained for the new tool compared to re-sharpened tool. Additional microscopic observations of some re-sharpened teeth showed deformed plastic characteristics.

The principal objective of this study is to apply the response surface methodology (RSM) to modeling and optimize the cutting-edge quality of three distinct types of PBs ( Standard M60, Eucalyptus Bark EU, and fine-urea FU) under modified sawing conditions. The experimental work was conducted using a multi-function sawing machine equipped with a circular saw that was instrumented with a pair of piezo-electric sensors, a high-performance vector AC drive, and a current transducer. The edge-profile quality was assessed by an artificial innovative vision system able to extract a virtual profile, and from this, delamination criteria were developed by applying a fast Fourier transform (FFT). RSM was used to optimize the delamination criterion ( Tw ), specific cutting energy ( Es ), and feed per tooth ( fz ) as response variables when influenced by the factors feed speed ( Vf ) and frequency ( N ). The optimization process showed that PBs with fine-urea (FU) yielded the best edge-quality performing results with lower Tw delamination factor, however, with higher specific cutting energy (Es) when compared to particleboards composed of 60% recycled wood (M60) and Eucalyptus-based composition (EU). It can be explained by the fact that the special FU composition contributes to a greater blinding contact zone of particles resulting in better aggregation and superior cutting-edge quality. Correspondingly, the numerical optimization indicates that the delamination factor (Tw) is lower for FU (representing only 9.3% higher than the desirable value, DV) when compared with the desirable values of the particleboard M60 and EU. In addition to this aspect of the FU composition, the physical–mechanical properties also influence the edge quality; these aspects are considered the ones that most affect the Tw response parameter. The lowest Tw value was obtained for N  = 50 Hz combined with a Vf  = 9 m/min, indicating these particular machining conditions positively affect this response parameter. In conclusion, this study demonstrated that both the experimental and prediction results correlated well and highlighted that the use of the RSM is appropriate for edge quality analysis of the specific type of PB machining conditions and response parameters considered in this study. In addition, the suggested system based on an artificial vision technique for evaluating edge quality exhibited good capabilities for implementation in an industrial environment.

Diamond wire sawing (DWS) is often used to cut and slice crystalline silicon. The machining accuracy of DWS is a key performance of wire sawing. However, due to the inconsistent deformation of diamond wire relative to the workpiece in different sawing directions, the machining accuracy is different. In this paper, the machining accuracy of DWS in rip sawing and cross sawing was compared. Sawing tests were designed for rip sawing and cross sawing in different feed directions. The length of sawing kerf was used for the evaluation of machining accuracy. It was found that the machining accuracy of diamond wire pushing the workpiece (rip +) is obviously better than that of pulling the workpiece (rip −) in rip sawing as the wire stiffness of rip + is higher. The machining accuracy of cross sawing in different feed directions is related not only to wire stiffness, but also related to the wire torsion produced by lateral feed force in cross sawing. Therefore, the order of machining accuracy 1X +  > 4Y −  > 2Y +  > 3X − shows that the cross sawing accuracy does not show an obvious law relative to rip sawing. A diamond wire electrical discharge sawing (DWEDS) was proposed in rip sawing and cross sawing to compare the machining accuracy of DWS. It was found that the machining accuracy of DWEDS is higher than that of DWS. No significant differences were found in machining accuracy between rip sawing and cross sawing in DWEDS. Finally, the characteristics of cutting force in time–frequency domain were analyzed.