Improving the quality of the band saw cut

This article is devoted to the study of the dynamic characteristics of the band sawing process to improve their efficiency. The object of study is: band saw, softwood. A screening experiment was carried out when sawing with band saws to identify key influencing factors on the quality of the treated surface (roughness) and sawing force (sawing power). Rational values of key influencing factors were determined. The effectiveness of the sawing regimes with band saws was evaluated. In the course of laboratory tests of the new saw, it was found that the moisture content of the wood has the maximum effect on the quality of the sawing walls. According to the degree of influence of factors, the roughness of the cut depends on the moisture content of the wood, the feed per tooth, the type of cutting relative to the wood grain and the height of the cut. As a result of a multivariate experiment, two regression equations were obtained for the assumed roughness of the cut and the cutting power. The estimation of the significance of the coefficients in the given interval of variation of the influencing factors is carried out.

Effect of Micro Textures on the Cutting Performance of Circular Saw Blade Under Fluid Lubrication

In this paper, linear micro textures that parallel to the sawtooth edge were fabricated on the surface of the high speed steel W6Mo5Cr4V2 circular saw blade by laser engraving. Further, cutting performance of micro textured circular saw blade (TCS) and traditional circular saw blade (CS), including sawing arc length, sawing force, sawing temperature, machined surface roughness and wear mechanism, were investigated in sawing 304 stainless steel pipes under the cutting fluid condition. Results showed that the largest sawing arc length and sawing force were occurred on the circular saw blade sawing outward from the inner wall. In addition, TCS circular saw blade exhibited better cutting performance and the mechanisms were found, on the one hand, the effective sawtooth-chip contact length was reduced due to the micro textures fabricated on the sawtooth surface, on the other hand, cutting fluid can be better penetrated into the micro textures and formed stable lubrication film in sawtooth-chip contact interface.

Sawing Status Prediction of Diamond Sawblade Sawing Concrete Based on the Characteristics of Material Composition

Diamond sawblade is an efficient tool to building renovation or demolition. Concrete used in construction is a typical composite material with random distribution, which is difficult to accurately identify and predict even under the same processing conditions, and tool life of diamond sawblade is difficult to control. In this paper, by cutting out single component of the hard and soft aggregate separately from concrete, the single component and concrete experiments were carried out to understand the sawing characteristics of different components. The wavelet decomposition was used to analyze the characteristic of each frequency band of the different components sawing force and vibration signals, and the sensitive frequency bands after correlation coefficient and energy ratio variation of each wavelet layer were extracted to judge the bluntness status of sawblade. By taking the Root-Mean-Square (RMS) value, the energy ratio of d2 and d5 wavelet layers and the standard deviation of sawing force and vibration signal as the characteristic values of the sawblade, a neural network optimized by bat algorithm was established to analyze the concrete processing signals and predict the working state of the sawblade. Evidence theory was adopted to combine the prediction results of sawing force and vibration samples to increase the overall prediction accuracy and reliability. The test sample showed that this method can correct inconsistent individual sensor predictions while being as close to the actual status value as possible. It provides an effective tool life prediction way of the diamond sawblade and a theoretical method for the monitoring of non-metallic materials with inhomogeneous components.

An Experimental Research on the Force and Energy During the Sapphire Sawing Using Reciprocating Electroplated Diamond Wire Saw

This study investigated the sawing of A-plane and C-plane sapphires using the reciprocating diamond wire saw. The influences of process parameters and sapphire crystal structure on sawing force were experimentally researched. The experimental results indicated that, in sapphire sawing process, the sapphire crystal structure, the wire speed, and the feed rate had effects on the tangential sawing forces, and the tangential forces had good linear relationships with the material removal rates (MRRs). The specific sawing energies in the stable stage were clearly smaller than in the unstable stage.

Random Vibration of Diamond-Beaded Rope Subject to a Concentrated Load

In this work, the random vibration characteristics of a beaded rope under a concentrated load are investigated. A stochastic model describing the sawing force of a single diamond-beaded rope was established, based on the principle of volume invariability. The governing equations of the beaded rope were obtained using Hamilton's principle. Theoretical expressions were derived to calculate the response power spectral density (PSD), load-response cross-PSD and the mean square value of the beaded rope lateral displacement, for a beaded rope subject to a concentrated load. The influence of the parameters on the random vibration characteristics of a beaded rope was analyzed, including the effects of the linear speed of the beaded rope, the tension of the beaded rope, and the location of the concentrated load. Numerical examples are given. Results show that as the tension of the beaded rope increases, the PSD and mean square value of the rope displacement are reduced. However, as the linear velocity of the beaded rope increases, the PSD and mean square value of the rope displacement are also increased. During movement of the diamond-beaded rope, the mean square value of the transverse displacement fluctuates predominantly, because of the time-varying impact force caused by the diamond beads.

Study on Force Characteristics of Ultrasonic Vibration-Assisted Sawing Ceramics with Diamond Blade

In the present research work, a new precision sawing technique is proposed, by which the ceramic workpiece is ultrasonically vibrated along the blade radial direction during the sawing operation using a diamond blade. In this study, experiments are conducted to study the sawing force characters of ultrasonic vibration-assisted sawing (UVAS) and conventional sawing (CS). The influences of the sawing parameters on the sawing force and force ratio are investigated. The results show that the sawing force in UVAS is smaller than those in CS. It was found that applying ultrasonic vibration to the sawing operation decreased the normal sawing force 18%-38% and tangential sawing force by 10%-25%. The force ratio in UVAS is lower than that in CS, which reveals that diamonds are easier to cut into the ceramic workpiece and the material machinability is improved.