The Velan Theory - What is Bimetal?
Bimetal is a composite material comprising two metals of largely differing
expansivities. When subjected to changes in temperature, this difference
in expansion causes the bonded metals to bend. This bimetal is specially
designed to meet the specific requirements in the Velan steam trap. It
resists corrosion even in most severe alkaline conditions (12 pH)., and acids
(2 pH).
Two bimetal materials have been specifically developed for use in
Velan Steam Traps
- For saturated steam service and superheat up to 520 deg F a bimetal with
the largest possible deflection and excellent corrosion resistance both
in alkalis and acids. Its temperature range is limited to 520 deg.
F.
- For superheated steam service up to 1100 deg F a bimetal of high tensile
strength unchanged at elevated temperatures. Deflection of this bimetal
does not increase above 600 deg F. Consequently, no additional stresses
are developed in the element when used on superheated steam. It can
safely withstand temperatures of 1100 deg F.