Data Sheet

Bulletin 71.4:66
3

  
 
NPT: 50 pounds (23 kg) for Type 66R or
65 pounds (29 kg) for Type 66RR
Flanged Ends: 55 pounds (25 kg) for Type 66R or
70 pounds (32 kg) for Type 66RR
 100 pounds (45 kg) for
Type 66R or 115 pounds (52 kg) for Type 66RR
155 pounds (70 kg) for
Type 66R or 170 pounds (77 kg) for Type 66RR

Special springs and other internal parts for
Type 66R set pressures from 1.5 to 5 psig (0,10 to
0,34 bar) and Type 66RR set pressures from
3.8 to 7 psig (0,01 to 0,48 bar); control line
connection for cast iron Type 66R; all-metal seats
for NPS 2 (DN 50) cast iron Type 66R
Figure 2. Operational Schematics
PILOT
CONTROL
SPRING
FIxED
RESTRICTION
PILOT
VALVE DISk
MAIN VALVE
DIAPhRAGM

PILOT
DIAPhRAGM

RETAINER
VALVE PLuG
SkIRT
STEM GuIDE

VALVE STEM
VALVE PLuG
SkIRT
MAIN VALVE
TYPE 66RR RELIEF VALVE
STANDARD TYPE 66R RELIEF

REGISTRATION
M1056M1041
INLET (CONTROLLED) PRESSuRE
OuTLET PRESSuRE
ATMOSPhERIC PRESSuRE
LOADING PRESSuRE