IOM-DA0
6
piston ring seal “slips inside” the cage (19).
Repeat process for second piston ring seal .
7. Place properly oriented seat ring (21) onto its
shoul der at the lower end of cage (19).
8. Install new lower stem o-ring seal (14) into
groove of plug (20).
9. Insert plug (20) upwards through lower end
of cage (19) and through the center hole in
piston-guide bearing (13), wiper washer (17)
and wiper seal (16). Hold plug (20) and cage
(19) assembly together.
10. Place the second new upper stem o-ring seal
(14) into groove of guide bearing (13). Position
stop plate (10) on top of stem seal and guide
bearing.
11. Thread nut (10) over the upper end of plug
(20) and tighten hand tight.
12. Place this assembly of parts into vise, use the
"flats" on the lower part of the plug to secure
tight. Use torque value as follows:
into the body (23). To secure cap screws tight,
rotate cap screws CW in equal increments in
one-half revolution increments to pull down
the ITA evenly, taking care NOT TO “AN GLE”
the ITA in the BODY. Torque cap screws to
13-15 ft-lbs (17.6-20.3 N-m).
6. Install new gasket (37) onto body (23) flange.
7. Aligning matchmarks and flange bolt holes,
place cover dome (25) onto body (23).
8. Install all flange bolts (11) and nuts (12) with
nameplate (99) located under one bolt head..
9. Tighten the body bolting (11,12) evenly in
an alternating cross pattern in one revolution
increments to the following torque values:
G. Pressure Testing:
1. If a hydrostatic pressure test is performed,
pressure 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 PRESSURIZED. NOT
AD HER ING WILL DO PHYSICAL DAMAGE
TO INTERNALS THAT COULD REN DER
THE UNIT IN OP ER A BLE.
Body Size
in (DN)
Torque Value
Ft-lbs (N-m)
1/2" - 1" (15 - 25)
60 - 70 (81 - 95)
1 1/4" - 2" (32 - 50)
120 - 130 (163 - 176)
2 1/2" - 4" (65 - 100)
110 - 120 (149 - 163)
13. This completes ITA reassembly.
F. Main
Reassembly:
1. Place body (23) in a vise.
2. Lower spring (22) into the body (23) and
center around the bushing.
3. Position the cage o-ring seal (15) down in
the body groove.
4. With the ITA held manually in the closed po si-
tion, carefully insert ITA into body (23).
NOTE:
Lower spring (22) must be compressed to al-
low the cap crews (18) to engage the threads
in the body.
5. Properly align all three cage bolt holes with
holes in the body. There is only one circum-
ferential location pos si ble for this align ment.
Use hand to apply downward force to the top
of the cage (19) until the ITA is lowered suf-
fi cient ly to engage the cage cap screws (18)
Body Size
in (Dn)
Torque Value
Ft-lbs (N-m)
1/2" - 2" (15 - 50)
30 - 35 (41 - 47)
2 1/2" - 4" (65 - 100)
45 - 50 (61 - 69)
Figure 4:
Location of Auxiliary Ports
