Anti static weighing bellow for ATEX zone
Western has developed anti-static bellow in color for the flexible connection of mixers, feeders or vessels on weighing cells to supply lines, drain pipes or other way of air transport or powder transfer. These anti-static weighing bellows are suitable for ATEX zones.
Anti-static bellow resistivity certificate
ASTM- D- 257 RESISTIVITY CERTIFICATE
This is to certify that the sieves supplied are categorized as Static Dissipative as per ANSI/EIA standards & the Electrical Resistance tests performed as per ASTM- D-257
ANSI/EIA-541-1988 Standard on Charge Dissipation:
Charge dissipation by electrical conduction through the volume of the material or on the surface is an important property as it can allow the charge to be drained safely away from a sensitive material.
Charge dissipation is basically a measure of electrical resistance.
The ANSI/EIA-541-1988 standard specifies charge dissipation as resistivity in the units of Ohms/square, which is taken from the ASTM test D-257.
The EIA standards categorize materials into 3 levels of charge dissipation according to the surface and
A conductive material has a resistance of less than 1 x 104 Ohms.
A static dissipative material has a resistance of 1 x 104 Ohms or greater but less than 1 x1011 Ohms. An insulative material has a resistance of 1 x 1011 Ohms or greater.
Terminology/Units of Measure Surface Resistivity in Ohms/square and Volume Resistivity in Ohm-cm
Test Methods: ASTM D-257;
Dissipative: Ability to dissipate a charge by surface or volume conduction
Required Range Observed
Surface : 1.0 x 105 and <1.0 x 1012 5 x 107` Volume : 1.0 x 104 and <1.0 x 1011 6.6 x 109 Remark : The material is fit to be used in contact with food containing fat & also with aqueous. DOWNLOAD PDF