Data Sheet

Bulletin 71.4:66
2


TYPES
NOMINAL
BODY SIZE,
NPS (DN)
END CONNECTION
STYLES AND RATINGS
(1)




66R,
66RR
2 (50)
NPT or
CL125 FF anged
NPT, CL150 RF,
and CL300 RF
anged
3, 4 (80, 100) CL125 FF anged CL150 RF anged

(1)
: 8 psig (0,55 bar), including build-up
 : 10 psig (0,69 bar), including build-up

: See Table 1
 : See Table 2

NPS : 2-inch (51 mm)
NPS : 3-inch (76 mm)
NPS : 4-inch (102 mm)

See Figures 3 and 4

See Tables 4 and 5


 
Body and Body Piping: Cast iron  or steel
Spring Case: Steel
Diaphragm Case, Diaphragm Plates, Bottom
Flange, Spring, and Bolting: Plated Steel
Diaphragm Spacer when Used: Zinc-plated steel
Diaphragms, and Valve Plug O-Ring and Spring
Case Gasket when Used: Nitrile (NBR) 
or Fluorocarbon (FKM) (high-temperature)
Bottom Flange and Stem Gaskets: Composition
Diaphragm Case and Closing Cap
Gaskets: Neoprene (CR)
Sealing Washer and Spring Case Drive Screw when
Used: Carbon steel
Type Y602-10 Vent Assembly when Used:
Zinc/stainless steel/Monel
®
Snap Ring when Used: Bronze
Closing Cap, Adjusting Screw, and
Spring Seats: Zinc
Flapper Valve when Used: Brass
Seat Ring: Bronze  or stainless steel


Body: Ductile iron  or steel
Spring Case: Cast iron
Lower Casing Assembly: Cast iron and
stainless steel
Lower Diaphragm Plate, Stainless Steel Trim Only:
Stainless steel
Diaphragm: Nitrile (NBR)  or
Fluorocarbon (FKM) (high-temperature)
Lower Spring Seat: Zinc-plated steel
Back Disk Spring: Stainless steel
Pressure Setting Spring: Zinc-plated or
cadmium-plated steel
 OriceandDiskHolder:Stainless steel
Disk: Nitrile (NBR)  or
Fluorocarbon (FKM) (high-temperature)
Valve Stem: Stainless steel
Pusher Post: Stainless steel
Lever Assembly: Stainless steel
Mounting Bar, Fittings, and Bolting: Steel

 
-20° to 180°F (-29° to 82°C)
 
0° to 350°F (-18° to 177°C)

See Table 3

 
Internal  or external
 
External on pilot and internal in main valve

 
Control Line (if used): 3/4 NPT 
Spring Case Vent: 3/4 NPT  with
removable Type Y602-10 vent assembly
 
Pilot Body: 3/4 NPT 
Pilot Lower Casing Assembly: 1/2 NPT 
Pilot Spring Case: 1/2 NPT 
1. The pressure/temperature limits in this Bulletin and any applicable ASME standard should not be exceeded.
2. Monel
®
is a mark owned by Special Metals Corporation.
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