Wafer devices are a specialized type of permeation tube where only a small area of the tube is permeable, creating a window—or wafer—that allows very low permeation rates. Like perm tubes, wafer devices are small, inert capsules containing a pure chemical compound, but permeation occurs only through the polymeric wafer; thus, the permeation rate can be controlled by varying the wafer material, thickness, and diameter of the permeation opening.
Gases with a high vapor pressure at normal permeation temperatures sometimes cannot be contained in a typical permeation tube device. Wafer devices are ideal for applications with these gases. VICI Metronics wafer devices are available in different styles for use in calibrators made by various manufacturers.
Contact us for more information about the list of standard chemicals available. Experimental and non-standard chemicals are also available on request.
View a sample of the Instruction Sheet and Calibration Certificate that are provided for each wafer permeation device
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