Sawing Machine Research Articles

Investigation on sawing performance of diamond frame saw based on reciprocating swing in processing hard stone

An innovative motion mode of reciprocating swing was introduced in frame saw for cutting hard stones in this research. Further, the theoretical models for the prediction of sawing depth and sawing interval of single segment were established, respectively. Sawing experiments and sawing forces test were conducted on the frame saw prototype with the new motion mode to investigate the cutting performance in sawing two types of hard stones. The results demonstrated that the application of the innovative sawing mode resulted in effective shortening of the length of sawing arc, reduced the number of segments involved in sawing simultaneously, avoided the instability of sawblade, and ensured that the sawn slabs met the requirements of qualified products. The segments on sawblade surface were divided into “front end”, “middle end”, and “rear end” according to the difference in contact pattern between the segment and the block. Segments in the middle of sawblade usually participated in sawing at the same position with unequal forces in forward and backward strokes, and the distribution of the sawing forces depended on the position of segment on sawblade surface. However, segments welded in the front end and rear end of the sawblade made an instantaneous cut once at one of the reversing points with higher sawing forces during reciprocating strokes. The sawing force value was found to be positively correlated with the feed rate, negatively correlated with the spindle speed, and also correlated with the stone characteristics. This new sawing mode provides a new approach for frame sawing machine to improve the sawing performance in sawing hard stones.

Research on economical sawing equipment for auto roll-forming frame part adapted to fast switching of multiple varieties

Precise angle sawing is an important process to ensure the auto roll-forming frame parts be assembled and welded accurately. Large enterprises can adopt special sawing machine and fixture to meet the requirements. However, this method is not suitable for small enterprises due to its large investment and insufficient flexibility of the manufacturing system. Considering the multi-varieties and small batches production characteristics, economical sawing equipment based on the general cutting machine platform equipped with quick change fixture is introduced. By changing the fixture position on the platform, and replacing a few necessary elements, this equipment can accomplish different angle precise sawing for various auto roll-forming frame parts. Finally the economical technology renovation purpose is realized.

К ВОПРОСУ ПОДГОТОВКИ РЕЖУЩЕГО ИНСТРУМЕНТА ПРИ РАСПИЛОВКЕ ЛЕСОМАТЕРИАЛОВ НА ЛЕНТОЧНОПИЛЬНОМ ОБОРУДОВАНИИ

the main drawback of circular sawing machines is the presence of broken teeth in the cut. In case of vibrations, violation of the saw plane, mismatch of the feed direction with the saw planes, and rebasing, these teeth spoil the processing surface. Belt sawing allows you to ensure high quality of lumber on the roughness of their surface at high feed rates; increase productivity by 1.5-2 times due to mechanization and automation of technological operations. One of the most important advantages of band saws is the small width of the cut, which is 1.5-2 times smaller than that of the sawmill; the small thickness of the saw ensures low consumption of wood in sawdust and high volume output of lumber. Sawing wood on band saws, in the vast majority of cases, is characterized by face cutting. Of the 3 forms of chip formation when cutting into the end, for band saws, the most characteristic is the formation of the chip element by chipping it with the stratification of wood along the bottom of the cut. The quality of the surface, in terms of its roughness, in addition to the formation of the chip element, is affected by its location in the interdental space, the presence and degree of compression and transportation of the chip element. The quality of the surface, in terms of its roughness, in addition to the formation of the chip element, is affected by its location in the interdental space, the presence and degree of compression and transportation of the chip element. As a result of studies of the initial conditions for the development of the teeth sharpening scheme, the orientation of the active elements of the blade relative to the middle plane of the saw can be identified as the main ones.

A Critical Reanalysis of Uncontrollable Washboarding Phenomenon in Metal Band Sawing.

The article analyzes the cutting process of hard bars. Investigations conducted in industrial conditions demonstrated the presence of surface errors in the machined workpieces in the form of washboard patterns. The purpose of this study was to analyze the results of cutting on band sawing machines with different band saw blades. The cutting processes were conducted on three different horizontal band sawing machine types. Analyzed material was an alloy steel Ø40 mm rod with a hardened surface covered with a thin layer of chromium. The hardness of the outer layer was 547 HV with a core hardness of 180 HV. The surface topography measurements of the processed workpieces were carried out with the 3D Optical Profiler, which supplied information on the irregularities of the processed material texture. In each of the analyzed cases, a corrugated surface was obtained after sawing, which is the effect of the occurrence of the washboarding phenomenon, despite the fact that the teeth of each band saw had variable pitches. The washboarding phenomenon when cutting rods with hard surfaces is caused by the phenomenon of wave regeneration. Despite the use of variable pitch saw blades, the cutting process results in rippling of the sawn surface, which is caused by the high hardness of the outer layer of the workpiece, as well as by the type of tool with spring setting of teeth.

Influence of wood modification on cutting force, specific cutting resistance and fracture parameters during the sawing process using circular sawing machine

The aim of this study was to determine the cutting force and specific cutting resistance of modified beech wood (Bendywood, DMDHEU and Lignamon) and, based on experimental results, to calculate the fracture parameters for cutting in axial–perpendicular direction of these modified materials and to compare with native beech wood. In the conventional approaches, cutting force and cutting power in sawing processes of wood are generally calculated based on the specific cutting resistance, which is a function of many factors. A major deficit of these conventional methods is that they are not focusing on the physical and mechanical properties of wood. The influence of these factors is only taken into account by the coefficient of the tree species. In this work, predictions of the newly developed model for the circular sawing machine are presented. Thanks to this modern approach, it was possible to determine fracture toughness and shear yield strength of native beech wood and modified beech wood using experimental results, without performing complex fracture tests. Based on the experiments performed, it can be concluded that modifications have a partial degradation effect on wood properties. The fracture toughness and shear yield strength of the modified materials is not dependent on the density, but rather on the internal structure, extent of the degradation of the cell wall and the type of modification

Innovative and optimized design of automatic adjustment system for beaded rope of new diamond wire sawing machine

Compared with traditional stone cutting technology, the diamond wire saw cutting technology is more efficient, safer and less polluting. Therefore, wire saw technology is more and more widely used in stone mining and other fields. However, the existing wire sawing machine must ensure the tension of the string bead wire at all time during the cutting process. Therefore, after cutting for a period of time, the wire breaking work must be performed, which greatly reduces the engineering efficiency, so this paper introduces a new automatic adjustment device of a diamond wire saw. Firstly, the overall structural design of the diamond wire saw is introduced. Secondly, the mechanical structure and sensing control of the automatic adjusting device of the diamond wire saw are introduced in detail. On the basis of the original wire saw, an adjustable wheel that can be automatically moved is added, and the working pressure of the string bead wire is measured in real time by a pressure sensor, the back and forth movement of the adjusting wheel can be controlled to drive the stretching of the string bead wire, thereby realizing the automatic tensioning of the string bead wire; Finally, working parameters of the wire saw are transmitted by Bluetooth or other wireless communications to achieve remote control operation of the wire saw. Through the innovative and optimized design of the automatic adjustment system for string bead wires of the wire saw, it provides a good reference for the high-efficiency, low-cost and environmentally-friendly quarrying technology.

Influence of Exhaust System Setup on Working Zone Pollution by Dust during Sawing of Particleboards.

Air pollution by wood dust in furniture production sites is an important hygiene issue. The dust is created by all types of wood and wood-based material machining, and its concentration in the working zone surrounding the machining stand depends on the effectiveness of the dust exhaust system. In present research, three setups of the dust extraction system for a conventional table sawing machine are considered while machining particleboards. The results showed a high impact of the exhaust system connection setup on the dust concentration in the air surrounding the sawing machine work stand. The use of both main and auxiliary sawdust extraction connectors together ensured the highest clearness of the air, with only 0.5 mg/m3 of dust concentration. Closing the upper hood leads to a concentration five times higher, while disconnecting it results in a ten times higher dust content. The finest dust particles (<1 µm), however, are the most numerous in the case of closing the hood.

Failure Prediction of Circular Sawing Machines Based on Condition Evaluation and ARIMA Model

As the starting point of cutting, sawing is an important link in the production process. Circular saws have high precision and high sawing efficiency. Once a failure occurs, it will bring considerable losses. This paper presents a fault prediction method for circular saw based on state evaluation and ARIMA model. According to the mechanism of failure analysis, considering different parameter indicators for different failures, we first find out the components of the equipment involved in these parameters, and adopt the entropy weight method and trapezoid-triangular membership function model to determine the health status. The key mechanism of the components in poor condition is predicted using the ARIMA model, and the weighted method is used to predict the failure time.

Survival probability of zirconia-reinforced lithium silicate ceramic: Effect of surface condition and fatigue test load profile

ObjectivesThe present investigation evaluated the step stress accelerated test (SSALT) load profiles on the survival probability of a glass ceramic under two surface conditions (polished or roughened). MethodsSuprinity–ZLS blocks (Vita Zhanfabrik) were shaped into cylinders, cut in a sawing machine, and crystalized according to the manufacturer's instructions. 60 discs were obtained (Ø=12mm, thickness=1.2mm) and randomly assigned into two surface conditions: “p” polished surface (400–1200-grit SiC papers), and “r” roughened surface (200-grit SiC papers). Profilometry was performed in all discs to evaluate average surface roughness prior to flexural fatigue strength testing. 3 discs of each group were submitted to biaxial flexural strength in an universal testing machine (0.5mm/min) and the mean load to failure (N) was calculated to determine SSALT profiles. 27 specimens per surface condition were assigned into three profiles – Mild (n=9), Moderate (n=9), and Aggressive (n=9), and submitted to the fatigue test (60–320N, 140,000 cycles at 1.4Hz). The results were analyzed using the Kaplan-Meier and Wilcoxon tests (5%), 2-way ANOVA and Tukey test (α=5%). ResultsKaplan-Meier and generalized Wilcoxon showed (P=0.002) that polished groups showed higher survival probability than roughened condition (P<0.05). A rough internal surface impacted deleteriously on the fatigue strength and reliability of ZLS ceramic. Both surface conditions were more sensitive to the aggressive profile than the other profiles, even worst for the roughened group. Regardless the load profile, 0% survival probability was observed at 384MPa for polished condition. While for roughened, aggressive tested specimens did not survived 147MPa followed by moderate at 312MPa and mild at 384MPa. The failure modes showed fracture marks originating from superficial grooves for both surface conditions. SignificancePolished specimens are sensitive to the load profile variation, confirming the effect of surface morphology on the fatigue results.

Product lightweight research in green design

The wire sawing machine is a large-scale concrete structure cutting equipment and mining quarrying machine used in the wild, in order to reduce costs and reduce energy consumption during manufacturing, transportation and use, on the premise of ensuring its performance, it is of great significance to explore its lightweight design method. This paper uses a multidisciplinary approach to construct a research method model for product lightweight design, comprehensively considering the aesthetic principles and usability principles of products, combining structural optimization theory and Kansei engineering theory, referencing three points of modeling structure, material selection and usage, through to the two aspects of physical and visual lightweight quantitative evaluation standard to determine the optimal solution for lightweight design. First, use Solidworks to build a three-dimensional model of the wire sawing machine; then, use ANSYS Workbench to perform finite element analysis on the mechanical properties of the frame to confirm it has optimization space of the frame strength; finally, through topology optimization of the frame structure and the design of the machine casing, the weight of the mainframe was reduced by 23%. The physical and visual lightweight results verifies the feasibility of the lightweight design model applied in the product design process and provides a useful reference for the sustainable development of industrial products.

Revisiting the estimation of cutting power with different energetic methods while sawing soft and hard woods on the circular sawing machine: a Central European case

In the classical approaches, used in Central Europe in practice, cutting forces and cutting power in sawing processes of timber are commonly computed by means of the specific cutting resistance kc. It needs to be highlighted that accessible sources in handbooks and the scientific literature do not provide any data about wood provenance, nor about cutting conditions, in which cutting resistance has been empirically determined. In the analyses of sawing processes, the use of a model with elements of fracture mechanics involved is an alternative way. In this work, predictions of the newly developed model (FRAC_MOD) for the circular sawing machine are presented. Thanks to this modern approach, it was possible to reveal the usefulness of the FRAC_MOD, using experimental results data on fracture toughness and shear yield stresses of both Polish pine (Pinus sylvestris L.) and Czech beech wood (Fagus sylvatica L.). The achieved results were compared to the forecasted values obtained with classical models (CLAS_PL and CLAS_CZ), which are commonly applied in Central European sawmills. The carried out analyses allowed us to discover undesired effects in the form of underestimation of cutting power when applying the CLAS_PL and CLAS_CZ models. For that reason, the FRAC_MOD cutting model could be suggested for the prediction of energetic effects in cases of dynamical analyses and even unsteady cases.

Design and Experimental Study of Wire Saw Machine for Cutting Oil Pipeline

According to the structural characteristics of the oil pipeline, repair cutting quality requirements, designed a special cutting wire saw machine. The structural characteristics of the oil pipeline and the variation of the area of the steel pipe section and the slit width of the oil pipeline are analyzed. The structural form, working principle and technical parameters of the hydraulic power system of the wire saw machine are determined. The wire sawing machine cut the oil pipeline and tested it, and established a mathematical model of the cutting force, two correspondences were obtained, one of which is the beading cutting force and wear rate of the wire saw machine, and the other is the feed speed and cutting speed. Engineering practice has proved that the use of wire saws to cut oil pipelines is an effective cutting method, both cutting quality and cutting efficiency are superior to other cutting methods.

The Effect of Modification with Epoxy and Polyester Resins on Some Mechanical Properties of Pine and Chestnut Woods

In this study, the effects of epoxy and polyester resin applications on some mechanical strength properties of scots pine (Pinus sylvestris L.) and chestnut (castanea sativa) wood samples were investigated. Firstly, in the circular sawing machine, a different numbers of channels (2+1 and 3+2) were opened on the surfaces of wood samples. Then, these channels were filled with casting type epoxy and polyester resins. The density, modulus of repture (MOR), modulus of elasticity (MOE), and compression strength parallel to the grain (CS) tests were performed on the samples. According to the results of the study, the density values of pine and chestnut samples increased by 25% and 42%, respectively, depending on the number of channels after resin application. In addition, compared with epoxy resin applied samples, the density increase was higher in the polyester resin applied samples. After application of resins, a slight increase was observed in the MOR and MOE values of chestnut samples. However, CS values tend to decrease in these samples. In pine samples with resin applied, the strength properties (MOR, MOE and CS) decreased depending on the increase in the number of channels. Furthermore, the effect of the resin type on all strength properties of the samples was statistically insignificant.

Ağaç Malzemelerin Daire Testere Makinelerinde İşlenmesinde Testere Geometrisi ve Uygulama Koşullarının Önemi

Circular saw machines are usually used for cutting of the edge flattened parts to desired dimensions and angles, sizing of panels, grooving, jointing, rebating, etc. For this purpose, it can be stated that the selection of the cutter in machining is very important in terms of product quality and efficiency. It can be indicated that the main factors affecting saw blade selection are material density and humidity, cutting edge shape and type with rake and tool angle. In this study, saw blade geometry, its selection and factors affecting the process were studied in the machining of wood materials in circular sawing machines. Also, the problems and solutions proposal encountered in the circular saws during in sizing are stated.

PERANCANGAN MESIN GERGAJI KAYU UNTUK PERAJIN PALLET KAYU

Technology at all times continues to grow along with the progress of the times, not least in the furniture industry. In the development of timber techniques demands a quality product, it needs an effective and efficient process. This is also the underlying work of cutting timber. Initially the cutting of the wood was done manually by utilizing manpower and then changed using a whipsaw. The rapid development of technology makes hand saws rarely used and switches using sawing machines and saw tables. From the results of the design process of wood sawing machine summed up some things as follows: Dimensions of wood cutting machine 1500 × 1000 × 800 mm, saws used in circular or cyrcle wood cutting machine with a circular motion saw blade, The rotation is passed from the motor to the saw blade is not in the fox and using the same pulleys of 74 mm diameter, wood cutting machine using 2Hp power, the level of safety on the wood cutting machine after theoretical calculations ranging from the transmission system, axis, and frame that is 9.524 m / sec belt speed is said to be good because ≤ 30 m / sec. The axle is said to be safe because the shear stresses that occur in the shaft are smaller than the allowable shear stress of , and on the framework of the wood cutting machine the yield of the voltage is less than the yield strength material of 7,888 Mpa ≤ 207 MPa with deflection 0,096 mm, In transmission belt V used is V type A42 belt, Image modification work of wood cutting machine used for machine making process contained in attachment.

The Mechanical Modeling and design of saw frame in band sawing machine

현대 제조 공업이 고효율, 고정밀도와 경제적인 방향으로 발전 하면서 금속을 절단하는 띠톱 기계는 이미 철강, 기계, 자동차, 조선, 석유, 광산, 항공 우주 등 다양한 영역에서 광범위 하게 활용 되고 있다. 하지만 기존의 띠톱 기계들은 경험적으로 설계 되어져 왔으며 따라서 낮은 수명, 톱질 동작 상태에서 낮은 정밀도 및 저효율을 문제와 높은 제조원가 문제를 가지고 있다. 본 논문에서는 띠톱의 역학적 해석을 통해 띠톱 톱대의 설계 파라미터를 개선하는 방법을 제시 하였다. 실제로 빈번하게 사용 되고 있는 띠톱 기계를 모델링 하여 응력 분석, 피로해석을 시행 하였으며 이에 따라 톱대의 상세한 설계 파라미터를 도출 하였다. 그 결과 피로 강도가 피로 요구 사항을 만족 시키고 띠톱 기계의 정밀도와 효율이 크게 향상 되는 것을 확인할 수 있었다.

Research on Cutting Performance Optimization of Diamond Wire Saw

Due to the wire sawing machine cutting technology has the advantages of more efficient, safer, higher yield and less pollution than the traditional quarrying method, it has been widely used in the mining of mine stone. In order to better analyze and study this technology, combined with the research progress of domestic and foreign scholars, the wire sawing machine cutting technology has been comprehensively analyzed and summarized. Firstly, the current advanced modular design of the wire sawing machine is introduced. Secondly, the structural innovation of multi-rope wire sawing machine is introduced. The influences of cutting speed and feed rate on the wear of diamond bead rope and the cutting efficiency of wire sawing machine are analyzed. And on the basis of this, the motor is under PID controll to find the optimal speed value, and finally explain its future development.

Dynamic Performance Optimization of Circular Sawing Machine Gearbox

To optimize the rigidity and dynamic mechanical properties of a sawing machine and improve its processing quality and stability, a design method for the sawing machine’s gearbox was proposed. First, a lightweight design of the gearbox was realized by topology optimization. Second, the sensitivity of different design variables of the new gearbox was determined via sensitivity analysis of the objective function. Finally, multi-objective optimization was used to obtain the optimal solution for the gearbox. Considering the complexity of the internal structure of the gearbox assembly and the accuracy of the numerical calculation process, a modeling method with mass points was proposed. A comparison between the numerical calculation results and the operation mode analysis revealed that the former was accurate and can be applied to the verification of the optimized gearbox. By optimizing the vibration signals before and after, and the analysis of the end face quality of the workpiece, the results revealed that the optimized gearbox has a significantly reduced amplitude under various operating conditions. In addition, the vibration stability was improved, and the end face quality of the workpiece was significantly enhanced compared to that before optimization. This study serves as a theoretical reference for multi-body dynamics modeling and optimization of machine tools, and also outlines technical solutions for high-speed stable cutting with sawing machines.

Selection of Working Frequencies in Complex Plane Motion of Saws within a Woodcutting System

Abstract—A woodcutting system based on complex plane motion (translation + rotation) of the saw blades is promising in principle but proves unstable in practice. This may be addressed by selecting working frequencies of the saws that differ from the eigenfrequencies and other parametric frequencies of the system. To that end, those frequencies must be identified. In the present work, a mathematical model of the saw system is derived. Its mass and size are optimized. On that basis, an energy-saving sawing machine superior in performance to comparable machines is manufactured and tested.

Prospects for percussion sawing machines in production of high-strength dimension stone

One of the most labor-intensive operations in production of dimension stone is separation of a stone monolith from rock mass, cutting of the monolith into blocks and sawing of the blocks into slabs. This article reviews in brief the methods of cutting and sawing of high-strength rocks. The new method of percussion sawing is described. Based on the method, the structural layouts of machines for cutting and sawing of stone blocks are proposed. The percussi on sawing method is efficient in brittle hard and super-hard rocks such as granite and sometimes marble, with Protodyakonov-scale hardness from 6 to 20. The method provides high quality finishing of surfaces at average productivity and low cost of sawing. The authors describe various structural layouts and operation modes for different percussion sawing machines suitable for operation in stone quarries, stone working plants and workshops. The basic elements of percussion sawing machines are frame, percussion assembly, tooth saw, vertical and horizontal feed drives, and the cut blowing or washing facilities. The article describes the machine capacity calculation procedure confirmed by the experimental research data. The major machine parameters to affect its capacity are: blow energy of the percussion assembly, number of percussion assemblies, saw area at the contact with stone, seesaw velocity, and ultimate compression strength of stone. A new estimated figure is put forward as specific blow energy per kerf bottom surface. The change in the capacity of a quarry percussion sawing machine as a function of time of one saw pass is determined. The obtained relation is compared with performance of other two types of sawing machines.The comparative analysis of mechanical methods of hard rock sawing is performed. The efficiency of the proposed method for percussion sawing of hard and super hard rocks is proved.