Most SIGMA transducers can be fabricated to operate at higher temperatures
than is generally available in the marketplace at large. For immersions
and contacts the primary concern in withstanding higher temperatures,
(other than fabricating materials such as epoxies, insulators, and solders),
would be the lens on an immersion and the wearface on a contact. Selection
of the proper materials, allows operation of these units up to 400 degrees
F continuous. For contact transducers, a vespel delay line can raise operation
to 450 F continuous and 800 degrees with a 15% duty cycle.
SIGMA transducers that utilize wedges, such as the integral wedge transducers
and the wedges for the SIGMA wedgemounts, have significant temperature
range depending on the material selected.
list provides the specifications for SIGMA High Temperature Transducers.
Temperatures given are for continuous contact:
F - Standard integral wedge transducers utilizing "Loten" wedges
and high temperature epoxies. Available
manual or mechanized 450
degrees F - Standard integral wedge transducers utilizing vespel wedges
and high temperature manufacturing materials. Available
manual or mechanized 1500
degrees F - utilizing steel wedges cut to the desired angle of propagation,
and mounted with compressional or transverse LiNbO3
high temperature transducers can withstand proportionately higher temperatures,
by observing a proportionately lower duty cycle on time to off time.
above materials are available for use with SIGMA wedges for wedgemount
transducers, except steel.
determine the unit to be fabricated to withstand the higher temperature,
specify the unit by part number, add the temperature indicator, and
specify "mechanized Unit" if desired.
please call SIGMA, or define the unit according to the "PART
is an example of a typical part No.:
describes the following unit: