ATEX Retractor System TANKO-RT/-RTS
3 Design and Function
Translation - Operating/installation instructions 2020/01
45/121
(3) Ignitable mixtures (e.g. carbon disulfide / air mixtures) require additional measures.
(4) Impacting cleaning jets form droplets or mists when they disintegrate that are normally charged and
generate electrical charges in the container. Existing turbulence distributes the charged mist throughout
the container, thus generating a high space charge density with high field strengths.
Note 1: The electric potential generated by the mist has its maximum has a maximum value in the
middle of the container and is dependent upon the type of cleaning liquid (e.g. water, oil or the use of
additive substances) and the parameters of the jet cleaner used (e.g. fluid pressure, flow rate and
nozzle diameter).
Note 2: Furthermore, isolated conductors can develop when cleaning with a water jet. Falling water
clusters can be charged by impact on the potential in the center of the tank. Ignitable discharges can
occur when the water clusters approach grounded conductive objects or the ground.
To prevent dangerous charges, appropriate measures must be taken for the design and equipment to
ensure with a very high level of reliability according to category 1 as per Directive 2014/34/EU, that the
relevant process variables
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Type of cleaning medium
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Conductivity of cleaning medium
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Operating pressure of cleaning medium
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Volume flow rate of cleaning medium
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Proportion of a 2nd phase in cleaning medium
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Container size
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Maximum number of retractor systems per container
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Temperature in the container to be cleaned and temperature of the cleaning medium
are complied with in accordance with the Technical Specification IEC/TS 60079-32-1 and TRGS 727 in
the valid version and as described in the operating instructions.