TPT-January-2015

Technology News

Self-calibration of measuring units increases accuracy

carried out. This extends from the in-house calibrating laboratorythroughaccredited calibrating laboratories up to the national metrological institute. Different standards, regu- lations and guidelines are valid for the expert carrying out of calibrations. A unit must fulfil basic requirements before a unit can be calibrated. One must also be aware of the physical conditions required in order to carry out a calibration and observe them. Rules for the calibration of instruments

ACCURATE calibration of measurement technology means establishing the measurement deviations on the measuring unit first, according to Zumbach Electronic AG. During the calibration process no technical intervention occurs with the measuring instrument, as opposed to cases of adjustment where a measuring instrument is set or adapted to keep the measurement errors as small as possible, or ensuring that the number of measurement errors do not exceed the error limits. The official calibration of a measuring unit is carried out according to the rules and regulations of the examining authority and the unit is marked with the respective stamp. The examining authority establishes whether the respective measuring unit fulfils the respective prerequisites. The validity of a calibration period follows practical requirements such as manufacturer’s information, require- ments of quality standards or company internalandcustomerspecificregulations, rather than an official calibration with a fixed time period validity for use. In order to be able to compare results of measurement, it must be possible to feedback information via a chain of comparison measurements to a national or international master. For this purpose, the display of the measuring unit in use, or the material representation, must be compared with the master’s in one or more stages. On each of these stages a calibration is carried out with a master, which has been previously calibrated by a higher-level master. According to the ranking of the master – of consumption or factory standards via reference masters up to national standards – there is a calibration hierarchy of points to be

The Zumbach ODAC 18XY

intervals in agreement with an in writing created program which contains specific guidelines, schedules, limits and accuracy and precautions for remedial actions if accuracy and/ or limits are not fulfilled”. European legislation has similar requirements. The company’s measuring units are calibrated using reference standards which were certified by the federal office for metrology (www.metas.ch) or by accredited laboratories. Each unit is supplied with a detailed calibration protocol. A regular check for measuring errors along with the corresponding protocol can be carried out according to customer requirements. The regularity of these calibrations is dependent on the customer specific requirements (internal regulations). Zumbach recommends a check of accuracy every 12 to 24 months.

are essential when a company decides to adhere to a specific norm or guideline or if it produces a product whose production is subjected to legal regulations. Standards and regulations such as the ISO 9000 series are becoming more important for quality assurance in all industrial nations. Then it may be explicitly required to calibrate all test equipment that directly or indirectly influences the quality of the product. This includes, for example, test equipment that is used as reference during the production process. Zumbach Electronic AG adheres to different standards and guidelines of quality assurance. The regulations of the FDA (American Food and Drug Administration), for example, are important worldwide in respect of international trading relations. The CFR (Code of Federal Regulation) demands that “devices, apparatus, measuring instruments and recording devices be calibrated at suitable

Zumbach Electronic AG – Switzerland Email: sales@zumbach.ch Website: www.zumbach.com Steel passivation process challenges QUAKER Chemical Corporation

options to meet process needs. The key benefits of the Primecoat line of products include a transparent appearance and corrosion protection.

that cause corrosion. Depending on the chosen chemistry and regulatory considerations, this process can be approached in several different ways. The Primecoat portfolio offers a product range consisting of hexavalent chromium (Cr6+), trivalent chrome (Cr3+) and chrome-free technology

featured its Primecoat™ passivation product line at the 106 th Galvanizers Association Meeting and Exposition in Jackson, Mississippi, USA. In the steel making process, the passivation step treats the surface to protect it from the environmental factors

Quaker Chemical Corp – USA Email: info@quakerchem.com Website: www.quakerchem.com

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J anuary 2015