7.2.1. Average operation time


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Fig. 7.5: Average operation time
Most pneumatic devices, such as tools, spray paint guns and blow-out guns are not in continuous use. They are switched on and off when needed. It is therefore necessary to find out the average usage rate UR in order to obtain an accurate figure for the compressed air requirement.

The following formula is used to determine the average usage rate UR:


    UR = average usage rate [%]
    TU = usage time [min]
    TR = reference time [min]
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<BR>Example

A semiautomatic screwdriver is in use for 25 min in the course of one hour.

The usage rate UR of the tool is 41,6 %.


The average usage rates UR of some widely used pneumatic devices is given in the following table. The figures are based on general experience and may deviate sharply in special cases.

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