Elastomeric Diaphragm Research Articles

Flexible column viscous spring damper

A viscous spring damper for damping and levelling structural agitation comprising a first outer member joined to a connecting member by a first elastomeric shear spring, the first outer member including a first fluid chamber and a first elastomeric diaphragm. A second outer member is joined to the connecting member by a second elastomeric shear spring and includes a second fluid chamber and a second elastomeric diaphragm. The connecting member is comprised of a plurality of elastomeric flexible sections which are disposed to form a main fluid chamber communicating with the first fluid chamber and the second fluid chamber, and further includes restrictive orifice for restricting the flow of fluid in the main fluid chamber.

Viscous spring damper

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Permeability of common elastomers for gases over a range of temperatures

For elastomers to be used in vacuum applications, their permeability should be low. Elastomers that are now, or likely to be, used in vacuum have been studied. The permeability of copolymers of fluoroelastomers and PTFE propylene (AFLAS) and a homopolymer of epichlorohydrin have been measured for hydrogen, helium, argon, nitrogen, carbon dioxide, and water vapor in the temperature range 20 to 120 °C. The test apparatus consisted of a restrained elastomer diaphragm with a pressure differential across it of normally 1 atm. The gas permeating is detected by a quadrupole mass spectrometer. The results obtained agree with already published values when they exist. The work further shows that for a given elastomer the temperature/permeability relation differs from gas to gas. The correlating of the measured permeability to the practical case of O-ring gaskets used in a vacuum system is discussed.