Diamante A&T Contents
Issue 100

Year XXV - December 2019

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Diamante A&T Magazine nr 100 or download the PDF file.






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Front Cover: SORMA SPA
Via Don F. Tosatto, 8 - 30174 Venezia-Mestre (VE), Italy

Sorma is an Italian company which works in the distribution of cutting tools for the metalworking industry and distribution of tools for the cutting and abrasion of stone, glass, ceramic, metal and composite materials.
Founded in Venice in 1950, Sorma has always focused on innovation as the winning ticket for offering the market the highest quality products available, paired with excellent service. This way of working is the main engine which is driving the development of the company that currently sees distribution of its own products in 57 countries and the reliable support of 100 employees.

www.sorma.net




In the Spotlight

10) Belzona, pioneering industrial repair and protection

12) 70th anniversary for Sorma




Diamond Tools

20) Evaluation of the performance of diamond wire cutters by means of experimental analyzes in marble quarries

by N. Auletta1, S. Bianchini2, M. Cardu1,3, P. Fresia1
1DIATI- Dipartimento di Ingegneria dell'Ambiente, del Territorio e delle Infrastrutture, Politecnico di Torino
2Mining Engineer, Carrara
3IGG-CNR, Torino

Abstract: Thanks to the evolution of cutting technologies, the extraction activity of the Carrara marble has undergone a considerable increase: over 20% of the material historically excavated has been exploited in the last 15 years. Annual production is around 1,400,000 t and represents the most important Italian activity in the dimension stones sector while the density of quarries in the Apuan area is 0.33/km2 (7 quarries/km2 for the municipality of Carrara only) compared to the national average, which is 0.02/km2 (Coli M. et al., 2002). These results were achieved thanks to the high performance of the diamond wire cutters, which made it possible to adapt the cuts to the morphological conditions of the quarries and to guarantee a high productivity. These machines are equipped with a driving pulley which supplies the rotation to the wire, that is made up of a steel cable on which the diamond beads are mounted, tools with a very small depth of cut which cause the material removal. The wire has a length of about 15-20 m for block squaring and greater than 60 m for upstream cuts. The cable is joined to form a "ring" by means of special pressure joints. During the exploitation cuts, the traction on the wire can reach values as high as to cause the joint to slip out, or even to break the wire itself, with projections of beads or pieces of wire. In some cases, the "whiplash" occurs: following a breakage of the wire between the machine and the block to be cut, the piece of wire undergoes further acceleration caused by the rotation of the driving pulley which remains in traction. This leads, in in some cases, to the detachment of part of the tool at speeds of about 600 km/h (Tantussi G., 2008)...
In case of tool breakage, therefore, the tension of the wire ranges values so high that the joint yields by loosening (the wire rope is unlikely to fail). What is not clear is instead how many kgf the wire needs to perform the cut. To date, there are no reliable indications, but only "sensations" from the operators and this is the reason why this research was carried out, starting from an experimental campaign at the quarry. Measurements were carried out on 3 types of machines in 3 different quarries, with amperage from 30 to 70 A. The results show that a simple squaring cut generally induces a tension on the wire of about 50 kg, while cutting a bench requires about 115 kg, and these values are well below the pull out strength of any type of joint.




Industrial Diamond

40) Quality analysis methods of synthetic diamonds for industrial use

by P. Lubatti
Poligem Srl

Abstract: Traditionally, the industrial use of diamond has always determined the need for a classification method that, based on standard parameters, would allow to select the suitable type of diamond for each application in order to get consistent results. Since the last century, the use of diamond for industrial applications has exponentially grown but, unfortunately, the increasing demand for this product was limited by the low availability of natural crystals. The development of synthetic diamond has overcome this problem: since the late 1950s, quantities have increased and in the seventies there was much more diamond than that available from natural sources. Moreover, the higher quality of crystals has led to an expansion of the fields of use allowing the processing of materials impossible to work just with natural diamond powder, like granites and quartzites. The increasing quantity and quality of synthetic diamonds available has stressed the need of tests based on the most objective parameters on one side and applicable to a massive production and application where repeatability and stability of each components must ensure an adequate and constant performance. Over the years, various methods have been developed for the qualification of diamond powders, starting from criteria used for the selection of gem diamonds: size, shape, purity.



50) Single-crystal diamond grit in construction: applications and characterization

by S. Nailer, S. Moseley, S. Huth, T. Klein
Hilti Corporation, Schaan, Liechtenstein

Abstract: Synthetic diamond in particulate 'grit' form remains the material of choice for the sawing and core drilling of construction materials such as reinforced concrete. Some sixty years since the first successful synthesis of diamond, diamond systems for construction applications continue to achieve ever-higher performance levels, deriving not only from increased capabilities of the power tools, but also from advances in the design and manufacturing of segments for 'inserts' (core bits and saw blades). One of the most significant developments in construction inserts in recent years has been the ability to position diamonds at specific locations in the segment. This paper begins with an overview of the applications of diamond power tools and their inserts in the construction industry, with a focus on the operating conditions of the applications and diamond particle wear and fracture behaviours. The paper then discusses the principal characteristics of diamond grit products for construction applications, provides insights into appropriate laboratory characterisation techniques, and describes how their results may be best interpreted to enable optimal diamond selection for today's advanced segment designs.



CNC Tool Machines

68) Remote monitoring of interconnected CNC tool machines in industry 4.0

by S. Chiavatti
UniversitÓ degli Studi di Perugia, Department of Mechanical Engineering, Perugia, Italy

Abstract: Nowadays modern CNC machines have an increasing number of tools able to allow remote monitoring and control. These tools are typically used by the machine manufacturers themselves and are often consistent in Numeric Control integrated applications that cannot be used by other brands. In addition, the factory organizes its management in various parts, including: security, maintenance and production. These parts run often separately and therefore require a system capable of collecting and aggregate global information. The paradigm of industry 4.0 allowed to exchange data for small and medium-sized enterprises, all fueled by the capacity of the new machine tools for transmitting these data through standardized communication protocols. This work was born in collaboration with the University of Perugia and two Italian companies: Comev and D.Electron, manufacturers of machine tool operations and Numerical Controls. The goal is to meet the emerging need of what mentioned above through the development of a remote monitoring system for CNC entirely developed with open-source technologies. The platform has a web-based interface that allows all operators to monitor all the desired information of each machine. This information is extracted and transmitted by the Numeric Control with the HTTP protocol. A web service with RESTful technology allow to store them in a SQL database from which they can be recalled and visualized in any time. The system is installed and running on a Comev Windows server and receives data from two corporate CNC where is set the data extrapolation program developed by D.Electron. Its operation is partially tested, with positive results, even on a third party with a PLC not developed internally by the company.



News and Events

77) History of the Global Stone Congress




Concrete Cutting

84) Dam these boys are good. CSDA contractor completes Allegheny river lock restoration project ahead of schedule