Table 1. Main Valve Body Sizes, End Connection Styles and Body Ratings
MAIN VALVE BODY SIZE
MAIN VALVE BODY MATERIAL
END CONNECTION STYLE
STRUCTURAL DESIGN RATING
NPS
DN
psig
bar
1 and 2
25 and 50
LCC or WCC Steel
NPT or SWE
1500
103
;DQG
25, 50, 80, 100,
150, 300 X 150
and 200
CL150 RF
CL300 RF
&/5)RU%:(
1500
103
Table 2. Outlet Pressure Ranges
TYPE
OUTLET PRESSURE RANGE
AC (ACCURACY CLASS)
PILOT CONTROL SPRING INFORMATION
psig
bar
EZH Series
EZHSO Series
Spring Color
Part Number
Wire Diameter
Free Length
In.
cm
In.
cm
PRX/120
PRX/125
PRX/131
WR
23 to 44
41 to 80
WR
WR
WR
WR
WR
Yellow
Green
%OXH
%ODFN
0;
0;
0;
0;
WR
203 to 334
WR
WR
WR
WR
Silver
Gold
Aluminum
0;
0;
0;
PRX/120-AP
PRX/125-AP
PRX/131-AP
WR
WR
Clear
0;
Table 3. Failure Mode Analysis
PART NAME
CONDITION
CAUSE
EFFECT
REGULATOR REACTION MODE
Type EZH
Type EZHSO
Filter
)LOWHU%ORFNHG&ORJJHG
'HEULVRUDURPDWLFV
present in the gas
'HFUHDVHRIVXSSO\
pressure gives decrease
of loading pressure
Close
Open
Pilot disk
Pilot cannot
be closed
'HEULVRUDURPDWLFV
present, Sour gas
,QFUHDVH
loading pressure
Open
Open
Pilot
lower diaphragm
Pilot cannot control
'HEULVRUDURPDWLFV
present, Sour gas
'HFUHDVH
loading pressure
Close
Open
Pilot
upper diaphragm
Pilot cannot feed
the regulator
'HEULVRUDURPDWLFV
present, Sour gas
'HFUHDVH
loading pressure
Close
Open
Regulator diaphragm
Not proper performance
of
the Loading
Pressure Chamber
'HEULVRUDURPDWLFV
present, Sour gas
%DODQFLQJRI3UHVVXUHV
and charge or discharge
of the loading pressure
chamber
Close
Open
Pilot
Frozen Pilot,
Type SA/2 working
0RLVWXUHLQWKHJDV
high-pressure drop
Type SA/2 loading upper
casing of regulator, Pilot
not supplying loading
pressure to
lower casing
Close
Close
3
EZH and EZHSO Series
