TPT-January-2015

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Technology News
30 January 2015
Self-calibration of measuring units
increases accuracy
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
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
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
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 ) 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.
Zumbach Electronic AG – Switzerland
Email:
Website:
Steel passivation process challenges
QUAKER Chemical Corporation
featured its Primecoat™ passivation
product line at the 106th 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
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
options to meet process needs. The
key benefits of the Primecoat line
of products include a transparent
appearance and corrosion protection.
Quaker Chemical Corp – USA
Email:
Website:
The Zumbach ODAC 18XY