Instruction Manual
D100399X012
EW Valve
July 2017
3
Figure 2. Cutaway Detail of the Fisher WhisperFlo Trim, Valve Body Typical
W6825‐1
Description
These single‐port globe‐style valves have cage guiding, clamped seat rings, and push‐down‐to‐close valve plug action.
Valve configurations are as follows:
EWD:
Balanced valve plug with metal‐to‐metal seating for all general applications over a wide range of pressure drops
and temperatures.
C‐seal trim is available for EWD valves, CL300 and CL600, in sizes NPS 6x4x2‐1/2, 6x4, 8x4, 8x6, 12x6, 10x8, and 12x8.
With C‐seal trim, a balanced valve can achieve high‐temperature, Class V shutoff. Because the C‐seal plug seal is
formed from metal (N07718 nickel alloy) rather than an elastomer, a valve equipped with the C‐seal trim can be
applied in processes with a fluid temperature of up to 593
_
C (1100
_
F), provided other material limits are not
exceeded.
EWS:
Unbalanced valve plug with metal‐to‐metal or optional metal‐to‐PTFE seating for all general applications
requiring better shutoff capabilities than can be obtained with the EWD valve.
EWT:
Balanced valve plug with either metal‐to‐PTFE seating (standard for all except Cavitrol III cages) for stringent
shutoff requirements or metal‐to‐metal seating (standard for Cavitrol III cages, optional for all others) for higher
temperatures.
Control valves with WhisperFlo cages (figure 2) provide additional attenuation for aerodynamic noise in very
demanding vapor or gas applications with high‐pressure drops. A WhisperFlo cage with an appropriately sized valve
body is designed to reduce the noise level up to -40 dBA. For special applications, -50 dBA attenuation can be
achieved.
Specifications
Typical specifications for these valves are shown in table 1.
