Brochure

is a drilled hole trim available in a variety of control
valve sizes and styles. It delivers excellent noise
reduction for a wide range of vapor, gas, and
steam applications. The design architecture allows
for flexibility of size, pressure class, materials,
rangeability, and attenuation.
n Up to 30 dBA of attenuation
n ASME Class 150–4500
n NPS 1–42
n Available in Fisher easy-e, EW, HP, EH, FB, TBX,
and GX control valves
n Hundreds of standard constructions as well as
a readily-available process to routinely provide
custom, application-specific constructions
n Typical materials ranging from carbon, alloy, and
stainless steels to titanium
Control valves utilizing Whisper Trim III cages
reduce noise through the following three means:
n Exit Jet Independence: Parallel passages ensure
jet independence and prevent additional noise.
n Frequency Shifting: Higher frequencies are less
problematic to hearing and process systems.
n Complementary Body Design: Emerson-engineered
valve bodies prevent secondary noise sources.
PRODUCTION: Baseload fossil power
APPLICATION: Gland steam
CHALLENGE: High steam velocity at the outlet of the previous control valve plus large pressure drops
created excessive noise and vibration, which posed a serious risk of stress or fatigue-related
damage to both the control valve and adjacent piping.
SOLUTION: Emerson-engineered Fisher NPS 2 HPS control valve with a Fisher Whisper Trim III cage.
RESULTS: Damaging noise was reduced and vibration was eliminated.
PROVEN RESULTS
Fisher
®
Whisper Trim
™
III Cage
10 | The Silent Treatment