Cashco 123 - Manual

II. INSTALLATION
IOM-123-BASIC
12-13
MODEL 123 — BASIC
BACK PRESSURE / RELIEF REGULATOR
SECTION I
I. DESCRIPTION AND SCOPE
The Model 123 is a back pressure relief regulator used to control upstream (inlet or P
1
) pressure. Sizes are 1/2",
3/4", 1", 1-1/2" and 2" (DN15, 20, 25, 40 and 50). With proper trim utilization, the unit is suitable for liquid, gaseous,
or steam service. Refer to Technical Bulletin 123-TB for design conditions and se lec tion recommendations.
SECTION II
6. Clean the piping of all foreign material in clud ing
chips, welding scale, oil, grease and dirt before in-
stall ing the valve. Strain ers are rec om mended.
7. In placing thread sealant on pipe ends prior to
en gage ment, ensure that excess material is re-
moved and not allowed to enter the regulator upon
startup.
8. Flow Direction: Install so the fl ow direction match-
es the arrow cast on the body. The body has an
angle con fi g u ra tion with a side inlet and bottom
outlet.
9. Regulator may be installed in a vertical or hor-
i zon tal pipe. If it is a steam system, ensure the
piping is properly trapped and oriented.
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 rec-
om mended that an inlet block valve, outlet block
valve, and a manual bypass valve be in stalled.
3. Pipe unions should be installed to allow removal
from piping.
4. An inlet pressure gauge should be lo cated ap prox-
i mately ten pipe diameters upstream and within
sight. An outlet pres sure gauge is optional.
5. All installations should include an upstream relief
de vice if the inlet pressure could exceed the pres-
sure rating of any equipment or the maximum inlet
pressure rating of the unit.
Recommended Piping Schematic for
Back Pressure/Relief Station
Discharge
Model 123-33
BP/Relief
Regulator
Supply @ P1
System
Demand
Bypass
SRV P1
P2
CAUTION A
This is not a safety device and must not be sub sti tut ed for a code approved
pres sure safety relief valve or rupture disc.
CAUTION B
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.
CAUTION C
Installation of adequate overpressure pro tec tion
is recommended to pro tect the reg u la tor and all
downstream equip ment from dam age in the event
of reg u la tor failure.
INSTALLATION, OPERATION & MAIN TE NANCE MANUAL (IOM)