Cashco DAP - Manual (Page 6)

IOM-DAP 6
align matchmarks from body (23) to cover
dome (25).
22. Insert bolting (11, 12) and hand-tight en. Final
tighten by torque wrench in an al ter nat ing
cross-pattern to the following torque lev els:
E. Converting Internal/External Sensing:
1. Disassemble the regulator and remove the
piston (77) according to Steps 1-10 in Part
B – Main Regulator Disassembly.
2. To convert from internal to external sensing,
remove the drilled pipe plug (32) and install a
solid pipe plug. Reverse this step for convert-
ing from external to internal sensing.
3. Reassemble the regulator according to Part
D – Main Regulator Reassembly.
F. Pressure Testing:
1. Model DAP has two different pressure rat-
ings – one for inlet, the other for outlet/cover
dome. If full inlet pressure hy dro stat ic test
is re quired, then it is necessary to fab ri cate
a "plug" to seal the "inlet zone" from "outlet
zone" of valve for this high pressure test.
VIII. PRESSURE LOADING
1. Loading pressure can be supplied using var i ous
schemes. Please reference LOADING SYSTEMS
on web-site for the schematics of these various
schemes, in clud ing:
• pressure unloading using BPV
• pressure loading using PRV
• pressure loading using pilot
• pressure loading using I/P transducer
SECTION VIII
2. If an outlet pressure rating hydrostatic pres sure
test is per formed, pres sure must be applied to
all three of cover dome (25), inlet and outlet
of body at the same level.
DO NOT HYDROSTATICALLY TEST WITH-
OUT COVER DOME PRES SUR IZED. NOT
AD HER ING MAY DO PHYS I CAL INTER-
NALS DAM AGE THAT COULD REN DER
THE UNIT IN OP ER A BLE.
3. Inboard Leakage Test.
a. Release all loading pressure in cover
dome.
b. Pressurize inlet to 50 psig (0.35 Barg)
with air, GN
2
.
c. Tube outlet to a beaker of water to ob serve
number of escaping gas bub bles.
Inboard leakage path may be via plug/seat
or dynamic side seal or both.
4. Pressure Containment Test.
a. Pressurize inlet to 200 psig (14 Barg);
outlet and cover dome to 150 psig (10.5
Barg) with air or GN
2
.
b. Soap solution test all external leak points;
plugged connections, cover and fl ange
and bolting.
5. Excessive leakage will require dis as sem bly,
examination of sealing elements, cor rec tion
of problem, reassembly and re test ing.
2. A Model DAP exhibits a deviation in outlet con-
trolled pressure when the inlet pressure var ies; this
“effect” is identifi ed as ISR – Inverse Sym pa thet ic
Ratio. Its relative pressure effect can be calculated
from following equation.
Body Size
in (mm) Torque
Ft-lbs (N-m)
Non-PED All Sizes 35-40 (47-54)
PED All Sizes 25-30 (34-41)