Emerson 112 Instruction Manual
Instruction Manual
Form 5864
September 2008
Type 112 Restrictor
Type 112
Introduction
Scope of Manual
This instruction manual provides technical
specications, installation, startup, adjustment, and
parts ordering information for the Type 112 restrictor.
Product Description
The 112 Restrictors are mainly used in natural gas,
air, or other non-corrosive gas applications. Their
installation is foreseen together with a Type 161 pilot
for Pressure Regulators Type EZR.
Specications
The Specication section lists pressure limitations and
other specications for Type 112 Restrictor.
Principle of Operation
The Type 112 restrictor controls the regulator’s
proportional band (droop) and speed of response.
The restrictor can be used to ne tune the regulator
for maximum performance by decreasing the restrictor
setting for tighter control (increased opening speed,
decreased closing speed); or increasing the restrictor
setting for maximum stability (decreased opening
speed, increased closing speed). A lower setting
also provides a narrower proportional band for better
accuracy. The “8” position has the largest ow, is
most stable, and easiest for startup, however, using
the “8” position is not necessary. The “0” setting has
the smallest (minimum) ow passage; at no point
of rotation will the Type 112 restrictor be completely
shutoff. After initial adjustment, the restrictor does not
need to be adjusted for maintenance or startup.
Startup and Adjustment
Startup for Both Single-Regulator and
Monitoring Installations
1. Make sure all block and vent valves are closed.
2. Back out the pilot adjusting screw(s).
3. For easy initial startup, set the restrictor to the “8”
position. For future startups, the restrictor can be
left in the desired run position.
4. SLOWLY OPEN the valves in the following order:
a. Pilot supply and control line valve(s), if used
b. Inlet block valve
c. Outlet block valve
5. For a 161 Series pilot with Type 112 restrictor,
turn the restrictor(s) to position “2” or to desired
run position. Set then the pilot to the desired
outlet (control) pressure according to the pilot
adjustment procedure. Refer to Tables 2 and 3 for
recommended settings.
Maintenance
Type 112 Restrictor
Perform this procedure only if O-rings are leaking.
Key numbers are referenced in Figure 2.
1. Unscrew the groove valve (key 22) and retainer
(key 23) just enough to loosen them, but do not
completely separate.
2. Push on the retainer (key 23) to push the groove
valve (key 22) out of the body (key 21), then
complete disassembly.
3. Replace the groove valve O-rings (key 24) if
necessary, being sure to lightly apply lubricant to
the replacement O-rings before installing them in
the groove valve (key 22) and retainer (key 23).
www.emersonprocess.com/regulators
D103237X012
Type 112
Specications
Maximum Inlet Pressure and Pressure Drops
Restrictor: 1500 psig (103 bar)
Flow Coefcients
Restrictor: See Table 1
(1)
Construction Materials
Body: CB7Cu-2 Stainless steel
Groove Valve: 416 Stainless steel
Retainer: 416 Stainless steel
Pipe Plug: 316 Stainless steel
O-rings: Fluorocarbon (FKM)
1. The pressure/temperature limits in this Instruction Manual and any applicable standard or code limitation should not be exceeded.
Table 1. Restrictor Flow Coefcients
SET ON START SET ON RUN
C
g
6 0.17 1 0.03 35
C
V
C
g
C
V
Table 2. Adjustment Recommendations with 161 and 161EB Series Pilot
SERIES
161 / 161H Pilots
161EB Pilots
Note: Higher Type 112 restrictor setting will increase proportional band. Adjustment of the Type 112 restrictor will also cause a shift in setpoint. Setpoint should be checked and
adjusted following restrictor setting adjustment.
RECOMMENDED TYPE 112
RESTRICTOR SETTINGS FOR LOW
FLOW OPERATION
Restrictor Setting of “5” or Greater
TYPE 112 RESTRICTOR SETTINGS
TO AVOID LOW FLOW OPERATION
Restrictor Setting of “2” or less if continuous
ows are expected to be less than 5% of
maximum capacity
C
1
Table 3. Adjustment Recommendations with 161AY / 161AYM Series Pilot
SERIES
161AY Pilots Restrictor Setting of “5” or greater
Note: Higher Type 112 restrictor setting will increase proportional band. Adjustment of the Type 112 restrictor will also cause a shift in setpoint. Setpoint should be checked and
adjusted following restrictor setting adjustment.
2
RECOMMENDED TYPE 112
RESTRICTOR SETTINGS FOR LOW
FLOW OPERATION
RECOMMENDED ORIFICE SIZE(S)
FOR LOW FLOW OPERATION
3/32 or 1/8-inch (2,38 or 3,18 mm)
(3/32-inch (2,38 mm) is standard)
TYPE 112 RESTRICTOR SETTINGS
AND ORIFICE SIZES TO AVOID
LOW FLOW OPERATION
Restrictor Setting of “2” or less if
continuous ows are expected to be
less than 5% of maximum capacity
Loading...