Papers by Keyword: Stone Cutting

Abstract: This investigation examines the possibility of adding niobium (Nb) to the Fe-Cu system in order to obtain, after powder compaction and sintering, a binder material (bonding matrix) with the adequate wear properties needed for the fabrication of diamond impregnated tools for stone cutting. The main objective is the replacement of cobalt (Co) by Nb in the Fe-Cu-Co alloys that are currently used in diamond tools. For this purpose, a comparative study has been conducted on some selected compositions of matrices integrated in cutting discs. Results of diamond impregnated 25wt%Fe-50wt%Cu-25wt%Nb and 25wt%Fe-50wt%Cu-25wt%Co matrices are directly compared because all tests were conducted under similar conditions. Two types of diamonds were used: without coating and Ti-coated. After the hot-pressing cycles, the main mechanical properties of the sintered bodies were evaluated. Cutting tests under real conditions, in Porriño granite, were carried out to compare the performance of the tools. Although the mechanical properties of the matrices with Nb were different from those found in the matrices with Co, the results obtained from the cutting tests have revealed that the tools made of 25wt%Fe-50wt%Cu-25wt%Nb and 25wt%Fe-50wt%Cu-25wt%Co matrices, both with 50/60 mesh diamonds, show quite similar behaviour during the cutting operations, thus indicating that replacement of Co by Nb is a promising route to be followed in the near future.

Abstract: The research disclosed in the present paper reports a new computer algorithm to maximize tool productivity in circular sawing processes, as a function of the stone characteristics and the quality required for the product. This algorithm is currently applied in tool testing at the company FrontWave and will be used in a new type of numeric machine to cut stone, called LeanMachine®. This optimization algorithm essentially depends on three variables: cutting depth, forward speed and rotational speed (identified as the main variables quantifying the sawing process), and how the variables are related with the forces acting on the tool. The algorithm uses the data provided by the relationships between each of the variables and the force acting on the tool (the so-called “force plots”) to determine the optimum working conditions for each tool, aiming to maximize productivity and minimize wear and energy consumption. The algorithm works with different production strategies, involving quality versus productivity, a key factor in the stone industry. A rating is subsequently attributed to each tool, allowing the establishment of tool rankings that can be used as selection criteria by machine operators or automatically in modern cutting stone machines such as LeanMachine®.

Abstract: A nonlinear numerical simulation model of stone-cutting circular saw blade was developed for the purpose of understanding the mechanics of cutting process by employing LS-DYNA program. Based on the classical damage model theory and fracture criterion, the action of cutting stone is mainly considered as extruding sliding friction and pressing. The movement rule and wear mechanism were analyzed in stone cutting process. After the transient strain field was obtained, the corresponding pressure was calculated. The results showed the present method is applicable to forecasting and optimizing the cutting parameters for efficient control and improvement of separation.

Abstract: Thermally enhanced machining is an effective way of processing hard and brittle materials. The Wear performance of diamond saw blade cutting granite plate by Plasma-assisted heating is studied by a homemade experimental device. Investigation of the blade wear in different suspension and heating scan rate shows that by plasma arc heating, the tool wear rate has a significant reduction. A technology for the efficient stone machining and further industrial applications is provided in this paper.

Abstract: With the growing use of natural stone both in industrial field and in ornamental materials of building, Complex-shaped stone products are being dramatic increasing. It is necessary to machine it with flexible and automatic machines such as NC machining enters. Versatile tools such as shaped diamond mills are used. The wear mechanism of diamond mills in stone cutting is presented in this paper though experiments. The macro-geometries of diamond mills such as mill diameter, profile and weight are described. The changes of macro-geometries of shaped diamond mills can be used to express tool wears. The changes can therefore be used to forecast tool wears in stone machining.