Cashco 1000 Cryogenic - Manual (Page 2)

2 IOM-1000HP-Cryogenic
drip melted condensate as re quired. A purge gas
is recommended for the spring cham ber.
10. Regulators are not to be direct buried under-
ground.
11. For insulated piping systems, recommen dation is
to not insulate regulator.
12. Cashco does not recommend fi eld welding on
the cyl in der (inlet) end of the regulator, due to the
possibility of warpage.
SECTION III
III. PRINCIPLE OF OPERATION
1. The Model 1000 is available in two vari a tions:
1000LP (larger diaphragm) for down stream pres-
sure control from 1-30 psig; 1000HP (small er dia-
phragm) for down stream pressure control from
10-300 psig, body size dependent.
2. Movement occurs as pressure variations reg ister
on the diaphragm. The registering pres sure is the
outlet, P
2
, or downstream pressure. The range
spring opposes di a phragm move ment. As outlet
pressure drops, the range spring pushes the
diaph ragm up, opening the port; as outlet pres-
sure increases, the dia phragm push es down and
the port closes.
3. The Model 1000 includes a rocker arm in its op-
er a tion al mechanism. The rocker arm allows the
regulator to operate fl ow-to-open (FTO), rather
than conventional fl ow-to-close (FTC), which
increases rangeability.
4. Due to the FTO design, there is a limit as to how
low of a downstream (P
2
or outlet) pressure level
setting is capable for a given inlet P
1
pressure.
This is a function of the ratio of the port area to
di a phragm area. It is possible for there to be too
high of an inlet pressure for the regulator to close
off against. (Refer to Technical Bulletin, Tables 6
and 7 for limits.) Reduced port, Option -12 allow s
low er down stream (P
2
or outlet) pressure set tings
for a given up stream (P
1
or inlet) pressure level.
5. The FTO design also is limited by a minimum
pressure drop. If the regulator pressure drop is
below 5 psi, an Option 1000-17 Piston Spring
should be utilized to assist open ing the valve
piston. (Standard with 1000-5; must be speci fi ed
with 1000-36.)
6. The Model 1000 includes an aspiration jet ef fect,
due to the clearance of the piston from the body
near the regulator's outlet. These clear ances vary
as to whether the fl uid is a gas or a liquid. Jets
must be se lec ted to match one of these two gen-
eral fl uids. An improper jet selection will reduce
perfor mance.
7. A complete diaphragm failure will cause the regu-
lator to fail open.
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.
9. For best performance, install in well drained
hor i zon tal pipe. Recommended position is with
spring chamber vertically downwards. Orient to
prevent the spring cham ber vent hole from col-
lecting rainwater or debris, and so drain hole can