Description; Specifications - Fisher EHD Instruction Manual

EH Valves (NPS 8 through 14)
End Connection Styles
Buttwelding: All available ASME B16.25
schedules that are compatible with ASME B16.34
pressure/temperature ratings
Flanged Ends: CL1500 or 2500 J raised-face
(RF) or J ring-type joint (RTJ) flanges per ASME
B16.5
Shutoff Classifications
See table 2
Bore seal trim: High-temperature, Class V.
See table 3
Flow Characteristic
Standard Cages: J Linear, J equal percentage,
or J modified equal percentage
1. The pressure or temperature limits in this manual and any applicable standard limitations should not be exceeded.
2. Valves using an equal percentage cage may be travelled an additional 13 mm (0.5 inch) if desired to obtain additional capacity; flow characteristic becomes modified equal percentage.
Table 2. Shutoff Classifications
VALVE
DESIGN
EHD
EHT
(2)
EHT w/ PEEK
Anti-Extrusion Rings
1. Per ANSI/FCI 70-2 and IEC 60534-4
2. Poly Ether Ether Ketone

Description

The EHD and EHT valves, shown in figure 1, are
large, sliding-stem, high-pressure, globe-style
valves. These valves have metal seats, cage
guiding, and push-down-to-close valve plug action.
2
Table 1. Specifications
(1)
(2)
(1)
ANSI/FCI
LEAKAGE
CLASS
III—Standard
IV—Optional
IV—Standard
V—Optional
V to 316_C (600_F)
Whisper Trimr III Cages: J Linear or
J modified characteristics available upon request
Flow Direction
Normally flow down (in through the cage windows
and out through the seat ring) for all cage styles
except for applications using either a Whisper
Trim III cage or a diverter cone plug, both of which
are flow up only
Additional Specifications
For specifications such as materials, valve plug
travels, and port, yoke boss, and stem diameters,
see the Parts List section
Approximate Weights
See table 4
The EHD and EHT valves feature balanced valve
plugs. To provide a seal between the valve plug and
cage, the EHD valve plug has piston rings; the EHT
valve plug has a pressure-assisted seal ring.
Bore seal trim is available for EHD valves, CL1500,
NPS 8 and 10 and CL2500, NPS 8, 10, 12, and 14.
With Bore seal trim, a balanced valve can achieve
high-temperature, Class V shutoff. Because the Bore
seal plug seal is formed from metal (N07718 nickel
alloy) rather than an elastomer, a valve equipped
with the Bore 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.

Specifications

Specifications for the EHD and EHT valves are
shown in table 1.
Instruction Manual
April 2009