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N E W S F L A S H February 2010 Standards against product piracy? • Continued from page 1 However, we actively fight against counterfeiters and forgers with the aid of our lawyer and, if need be, by taking court action. In China and soon in further hub markets, the security service provider “Pinkerton Consulting & Investigations” supports us in closing down the factories of counterfeit manufacturers and detecting the trade flows of pirate copies and counterfeits. Contrary to T-shirts and sneakers, abrasive counterfeits not only damage the business of the original manufacturer but also pose a serious safety risk to the end-user often resulting in fatal injury. With great interest, oSa pursues initiatives emanating from the ISO to set up globally valid standards for the quick identification of counterfeits. Customs and police authorities are today often faced with the problem of having to quickly and accurately identify counterfeit products. Even oSa-members have difficulties in identifying them as counterfeit. It is therefore advantageous that oSa-representatives are able to participate in the respective ISO Standards Committees where they can represent the interests of our members. We can only hope that solutions will be implemented there which also help oSamembers to protect their products reliably against counterfeits or at least will make the detection of counterfeits easier and more certain. Further information on this standardisation project can be obtained at the ISO-Secretariat ISO/PC 246 „Anti-counterfeiting tools“, which is operated by the French standards institute AFNOR. The current draft standard is: ISO WD 12931 „Performance criteria for authentication tools for anti-counterfeiting in the field of material goods“. Innovative oSa-products? You will say: Stop! It goes without saying that also oSa ® - labelled products are innovative. What does this topic have to do with a newsletter? But be careful! The three EN- Safety Standards form the basic pillar of our safety philosophy. So far it was strictly regulated that only abrasives covered by the standards could be labelled with our protected trademark. And anyone who knows about standardisation processes is well aware that they need considerable time to formulate or modify. Time, on the other hand, is a factor that innovations lack, as they basically deal with the quick conversion of new technical and economic findings into product benefit. Someone who has found out how an abrasive can be considerably mproved, does not want to wait 5 years until the next standards revision. The product life cycles demand that the innovative tool is placed on the market quickly. The conflict of objectives lies in putting the innovation into practice for the end-user but at the same time making no concessions on the high safety requirements of the oSa. The Technical Working Group (TWG) has tackled this topic in detail. Experts from our member companies together with our independent inspectors have found a feasible way how it can be assured that product innovations fulfil all oSa-requirements. The manufacturer basically must take three steps to turn the innovative abrasive product into an approved product under the oSa-safety umbrella: 1. Risk assessment – which dangers for the end-user can emanate from the new product? 2. Identify which product already covered by the EN- Safety Standards has similarities to the new abrasive tool 3. Prove that the requirements stipulated for this „conservative“ product are also met by the innovative tool and, even better, exceeded For legal reasons, it will be impossible to label such abrasives with both oSa ® -trademark and EN-number. It must therefore be our aim to take innovative products into consideration at the next regular standards revision and to adopt them into the standards. The Board of Trustees put this new regulation into effect at its autumn meeting 2009. All members will be informed about the exact procedure of including innovative abrasives into the oSa-scope of products. Calculation of mounted points by means of the finite element method Geopolymers – a new bond?
S E R I E S T E S T I N G B Y T H E M A N U F A C T U R E R February 2010 Part 4: Impact resistance Our series aims to provide an overview of the different test methods for abrasives. The requirements of the safety standards are high, based on a decade-long experience accumulated by independent test institutes. It is the overall aim to ascertain that even in case of foreseeable misuse an abrasive will have resistance to failure. The protection of the end-user is the first priority for all oSa-members. So far we presented the burst speed test, the destructive segment test for diamond cutting-off wheels and dish wheels as well as the side load test. In the last newsletter we explained the single and three-point side load test. These tests provide information on the resistance of abrasives to side load and jamming. These two test methods are supplemented by the impact resistance that measures the resistance of the wheel to sudden lateral shock. This test is mandatory for all resinoid bonded depressed centre wheels (ISO-type 27, 28 and 29) as well as for depressed and straight cutting-off wheels (type 41 and 42), 150 mm diameter and above, for use on hand-held machines. The test principle is easy. The test sample is mounted to a spindle by means of flanges and then taken up to its maximum operating speed. The rotating abrasive is laterally subjected to one or several impacts supplied successively by means of a pendulum until failure. Details on the implementation of the tests can be taken from the EN 12413. Picture 1 shows the pendulum Picture 1: Pendulum applied at the IFA (formerly BGIA). The impact energy can be adjusted by changing the drop height or by loading additional mass. Picture 2: Breakage into several pieces One typical damage pattern is shown in picture 2. Besides regular function checks, the calibration of the test stand in certain intervals is important. For example, dirt that got into the bearing can increase the bearing friction and thus minimize the drop energy that impacts the abrasive. The IFA recommends to have the pendulum calibrated by an external institute at least once a year. M E M B E R P O R T R A I T Manufacturers of bonded abrasives Bonded abrasives are one of the most common and well known of the abrasive groups. Since grinding is one of the oldest manufacturing processes, you will be bound Mounted points to have come across this product group at some time. These products are also of major importance to oSa. One factor that all these bonded abrasives have in common is that they utilise conventional abrasives such as aluminium oxide and silicon carbide, not diamond or cubic boron nitride. There are also the newer zirconia-alumina and sol gel abrasives. Originally, there were numerous natural hard materials used such as sandstone, garnet, emery and corundum but these were found to be too inconsistent for modern requirements. The abrasive grains are held together by a bond. The type and nature of the bond determines the grinding characteristics obtained. There are several bond types available. Among the inorganic bond types, the ceramic or vitrified bond plays the decisive role within oSa. The use of silicate and magnesite bonds has diminished considerably in recent times. The most common of the organic bonds is resinoid bond, normally a phenolic (Bakelite). Less popular are rubber, shellac, epoxy or thermo-plastic bond types. With a market share of an estimated 2.2 bn. USD (as of 2004), bonded abrasives constitute the second biggest product group after coated abrasives. Although the handheld and mobile machines present the greatest safety risks, stringent safety requirements also apply to stationary machines. For example, an abrasive wheel for highpressure steel conditioning can easily weigh several ten kilos and operates at speeds up to 80 m/s. Its bursting would have serious consequences, not only for the worker, (since not all machines are totally-enclosed), but also the machine could be badly damaged. Grinding process There are currently 25 manufacturers of bonded abrasives who are members of oSa. Many of them have played a decisive role as founding members in formulating the oSa-safety philosophy. Substantial aspects of this philosophy also found entry into the European Safety Standard, EN 12413. This standard was revised in 2007 and now offers a solid basis for the self-certification of the oSa-members. The oSa-trademark on an abrasive wheel provides the end-user with a sense of security as it indicates a product with a high and verifiable level of safety. Vitrified bonded wheel
Page 1: Newsletter February 2010 Standards

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