Measurement And Simulation Calculation of Wire Bow Angle During The Diamond Wire Saw Process

The wire bow angle is an important factor that affects the shape precision of an ingot after the diamond wire sawing process. In this research, the wire bow angles of the inside and outside of an ingot were recorded with a high-speed camera. The effects of the processing parameters such as the wire tension force, feed speed, and wire speed on the wire bow angles inside and outside the ingot were analyzed. A numerical simulation model of the wire bow in the wire sawing process is presented in this paper to describe the wire bow angle inside the ingot. It was shown that the wire bow angle inside the ingot was smaller than that of outside the ingot for all of the processing parameters. The wire bow angles improved with the increase of the feed speed and decrease of the wire speed and the wire tension force. The results of the wire bow angle measurement of the inside ingot and the simulation calculation were similar for the process parameters.

Influence of bandsawing processing parameters on the preparation of cortical bone flake

Natural cortical bone is an important source of bionic bone repair materials. Sawing cortical bone is the first and important process in fabrication bone repair materials. However, the high sawing temperature could cause damage to bone tissue and nerves, and surface roughness should decrease osteoinductivity. In order to improve the cutting performance during sawing cortical bone, and the quality of prepared cortical bone slices, the band sawing process should be investigated and improved. In this paper, the novel cortical bone sawing experiment was designed with different feed rate and tooth pitch. Then, the influence of experimental parameters on temperature and roughness were analyzed with Analysis of Variance (ANOVA). The experimental results show that the lowest value of temperature is 35.5°C (tooth pitch is 8.46 mm, feed rate is 35 mm/s), the highest one is 73.8°C (tooth pitch is 4.20 mm, feed rate is 5 mm/s). And the turning point of surface roughness appear when the feed rate is 20 mm/s. Otherwise, the prediction model of sawing temperature and surface roughness could help to find optimal band sawing parameters of natural cortical bone.

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.

Experimental Analysis of Abrasive Diamond Tool Wear and their Cutting Force in Stone Machining Process

Stone machining with a diamond tool is a common procedure for producing both standard items and design shapes, such as tiles, slabs and so on. During the entire deep sawing process of a granite work piece with finite length cutting procedure in stone processing, force components acted on the saw-blade. The work is split into two parts: theoretical and practical. The theoretical section discusses the features of diamond blades, cutting process methodology, and stone mining and processing methods. The practical portion of the project focuses on the wear of diamond blades when cutting stone, notably granite. The overall weight of the cutting blade and the loss of tooth height as a function of time are used to determine blade wear for two cutting blades from different manufacturers. There is a linear relationship between the two measured values. The findings serve as the foundation for a cost-benefit analysis of both diamond wheels.

Features of forensic commodity examination of upholstered and cabinet furniture

The main task solved by forensic experts while studying furniture is to define its quality conditioned by a complex of consumer properties formed in the process of manufacturing and maintenance of such furniture. The purpose of this article is to study main signs allowing to identify falsification or counterfeiting of furniture, and requirements for labeling. The upholstered furniture of the provided manufacturer is characterized by the following features: a frame is made of natural wood, dried automaticallyin compliance with all norms and standards; particular attention is drawn to the quality of components; high-quality foam rubber is used to fill the mattress blocks which are tested for elasticity, wear resistance, certification, etc. Cabinet furniture of the provided manufacturer has the following characteristics: high quality workpieces, smooth, without knots along the entire length of a saw cut; wood edges are straightened at all areas of parts; when drilling attachment holes, the vertical and horizontal drilling accuracy is strictly controlled; furniture fittings correspond to a general artistic decision of furniture, have a long service life. When conducting a forensic commodity examination of furniture, it is proposed to carry out its research in the following sequence: identify product characteristics, dimensional characteristics, shortcomings, causes of defects and their nature by the method of organoleptic examination and linear measurements; the method of comparative research establishes compliance or non-compliance of a studied product with regulatory requirements set for products of this commodity group, presence of defects in semi-finished products, quality of wood drying process, execution of the wood sawing process and manufacture of parts, quality of the process of manufacturing a frame, upholstery and finishing. When evaluating the quality of furniture, it is needed to take into account their compliance with requirements, governed regulations for design, standards and other documents.

Assessing the System Vibration of Circular Sawing Machine in Carbonate Rock Sawing Process Using Experimental Study and Machine Learning

Predicting the vibration of the circular sawing machine is very important in examining the performance of the sawing process, as it shows the amount of energy consumption of the circular sawing machine. Also, this factor is directly related to maintenance cost, such that with a small increase in the level of vibration, the maintenance cost increases to a large extent. This paper presents new prediction models to assess the vibration of circular sawing machine. An evaluation model based on the imperialist competitive algorithm as one of the most efficient artificial intelligence techniques was used for estimation of sawability of the dimension stone in carbonate rocks. For this purpose, four main physical and mechanical properties of rock including Schimazek’s F-abrasivity, uniaxial compressive strength, mean Mohs hardness, and Young’s modulus as well as two operational parameters of circular sawing machine including depth of cut and feed rate, were investigated and measured. In the predicted model, the system vibration in stone sawing was considered as a dependent variable. The results showed that the system vibration can be investigated using the newly developed machine learning models. It is very suitable to assess the system vibration based on the mechanical properties of rock and operational properties.

Laser DAF Cut: A Breakthrough Approach of Die Attach Film Singulation for Thin Wafers

Today, semiconductor world is becoming more inclined to thinner Integrated Circuit (IC) packages. IC packages will require thinning of the internal configuration of the package, which involves the die or the wafer and the adhesive material, which is the Die Attach Film (DAF). Aligned to this, as wafers goes thinner it becomes more of a challenge in process development especially during its preparatory stages, such as wafer back grinding and sawing processes. As the die becomes smaller and thinner wafer sawing process should have minimum effect on the mechanical integrity of the silicon so as not to alter its quality. New technologies were introduced so as to adopt to this development trend, one of this is the Dicing Before Grinding (DBG). Compared to the normal wafer preparation process that is wafer back grinding before wafer sawing, DBG flow is wafer sawing first prior wafer back grinding processes. The application of DBG technology eliminates the mechanical draw backs of the conventional wafer sawing process. In addition, with the use of DAF for thinner packages, DBG was developed together with the Die Attach Film (DAF) cutting solution, which is Laser DAF Cutting. DAF are separated using Laser as a cutting medium to address potential processability problems that may occur on the conventional mechanical blade saw. The paper discuss the Laser DAF cut development that covers the Design of Experiments (DoE) to understand the different characteristics of Laser DAF solution and be validated through actual simulation and wafer processing. The paper will also cover the interaction of different DAF thicknesses and Laser DAF parameters in order to define the critical characteristics so as to understand the behavior of different laser DAF parameters in achieving optimal DAF cutting process responses.

The mechanics of sawing granite with diamond wire

A theoretical model of sawing granite by means of a diamond wire saw, composed of a multitude of diamond-impregnated beads mounted onto a steel rope, is presented. The wire sawing process has been contrasted with circular sawing with respect to diamond loading conditions. The analytical treatments have been supported by industrial quantitative assessments and qualitative observations. The evaluation of cutting forces as well as identification of system characteristics affecting wire vibration and wire rotation are instrumental in both machine design and tool formulation. This knowledge is also useful to diagnose and prevent problems inherent in diamond wire sawing of granite, such as the high incidence of wire breakage, unsatisfactory tool life and cutting capability, eccentric bead wear, etc.