Cashco POSR-2 User Manual
Model posr-2, Pilot operated pressure re duc ing regulator
MODEL POSR-2
PILOT OPERATED PRESSURE RE DUC ING REGULATOR
SECTION I
I
. DESCRIPTION AND SCOPE
The POSR-2 is a pilot operated pressure reducing reg u la tor used to control downstream (P
2
) pressure. Sizes are
1", 1-1/2", 2", 3" and 4" (DN25, 40, 50, 80, 100). The unit is suitable for steam service only. Refer to Technical Bul-
letin POSR-2-TB for design conditions and selection recommendations. NOT RECOMMENDED FOR DEAD END
SERVICE.
SECTION II
II. INSTALLATION
A. General:
IOM-POSR-2
12-13
INSTALLATION, OPERATION & MAINTENANCE MANUAL (IOM)
6. Clean the piping of all foreign material in-
clud ing chips, welding scale, oil, grease and
dirt before installing the regulator. Strainers
are recommended.
B. Piping the Valve:
1. An inlet block valve should always be in-
stalled.
2. If service application is continuous such that
shut down is not readily accomplished, it is
recommended that an inlet block valve, outlet
block valve, and a manual bypass valve be
installed.
3. Pipe unions are recommended for NPT
screwed in stal la tions to allow removal from
piping.
4. An outlet pressure gauge should be located ap-
prox i mate ly ten pipe diameters down stream,
and within sight.
5. All installations should include a downstream
re lief device if the inlet pressure could ex-
ceed the pressure rating of any downstream
equip ment or the maximum allowable outlet
pres sure rating of the unit.
FIGURE 1
Recommended Piping Schematic for POSR-2
WARNING
Do not dead end (no fl ow demand) downstream of POSR-2
if P
1
- Inlet Pressure is greater than max i mum allowable
outlet design pressure.
Max.
Allowable
Spring Range
Outlet Pressure
5-15 psig (0.34–1.03 Barg)
100 psig (6.9 Barg)
10–40 psig (0.69–2.8 Barg)
200 psig (13.8 Barg)
30–80 psig (2.1–5.5 Barg)
200 psig (13.8 Barg)
70–150 psig (4.8–10.3 Barg)
200 psig (13.8 Barg)
CAUTION
Installation of adequate overpressure pro tec tion is recom-
mended to pro tect the reg u la tor from overpressure and
all down stream equip ment from damage in the event of
regulator failure.
CAUTION
For welded installations, all internal trim parts, seals and
diaphragm(s) must be removed from reg u la tor body prior to
welding into pipeline. The heat of fusion welding will dam-
age non-metallic parts if not re moved. NOTE: This does
not apply to units equipped with extended pipe nip ples.