AERCO Steam Generator - Manual (Page 19)

INSTRUCTIONS – AERCO HELITHERM STEAM GENERATOR MODEL SS1B-PLUS
SG-101-17
d. Using a torque wrench, tighten both
unions to approximately 75 ft-lb
while holding the coil so that the
turns of the coil remain perfectly
horizontal, where they are brazed to
the tail pieces, after tightening.
NOTE: Never use a hammer on a
wrench to tighten a union nut.
Deformation and subsequent
leaking may result.
e. Space the Coil tubes evenly
throughout the Generator, with each
tube space at least 1/2" wide. It is
especially important that no tubes
rest on any Coil unions. A spacing
tool may be made up similar to that
shown in Figure SG-101-7 (avail-
able from AERCO, Part No. 12523).
Insert the tool flat between the Coil
tubes and twist the tool until the
desired spacing is obtained.
f. Test for leaks per step D11 of the
DISASSEMBLY Section. Make any
corrections necessary.
R3. Clean all gaskets and gasket surfaces
thoroughly. AERCO recommends that
new gaskets (13) be used whenever
reassembling either the top or bottom
head to the shell.
R4. If the Generator Top Head (1) has been
removed from the Shell (11):
a. Clean the Gasket surfaces
thoroughly and place a Gasket (13)
(a new Gasket is recommended) on
the Shell top flange.
b. Replace the Generator top Head
onto the top of the Shell, lining up
the stud holes.
c. Reassemble the Studs (3) and (12),
the Lifting Lugs (Eye Bolts) (2), and
Nuts (14) into the Head and Shell
flanges. Cross-tighten the Nuts to
approximately 75 ft-lb torque to
obtain uniform seating. Then,
progressively tighten the Nuts to
approximately 150 ft-lb torque for a
tight seal.
d. Realign the Tubing (23) and
reconnect the Compression Fittings
(25) to their connections at the top
Head.
R5. Place the Gasket (13) on the Generator
bottom Head flange.
R6. Using a hoist or block and tackle
attached to the Lifting Lugs (2) on the
Generator top Head (1), CAREFULLY
lower the top Head and Shell
STRAIGHT DOWN over the Coil and
Riser assembly. DO NOT SCRAPE the
Shell lining against the Coil tubing.
R7. Before resting the Shell flange onto the
bottom Head flange, make sure that the
Shell is positioned properly by lining up
the marking put on the edges of the
flanges in step D7 of the DISASSEM-
BLY Section. For further assurance,
check to see that the raised indicators
on the outside diameters of each of the
top and bottom Head flanges line up
with each other. This is very important.
R8. Assemble the Studs (12) and Nuts (l4)
into the bottom Head and Shell flanges.
Tighten the Nuts in the same manner as
in step R4c above.
R9. Reconnect the Compression Fitting (25)
in the Primary Steam Pressure Gage
line and open the Shutoff Cock (38).
R10. Reconnect Union (29) located above the
Level Controller (34).
R11. Reconnect the air supply and control air
piping to the Control Box.
R12. Reconnect the power supply wiring to
the Control Box and all wiring between
the Control Box and the Level Controller
(34).
R13. Reconnect all external piping to the
Generator Top Head, including that to
the Relief Valve (24).
R14. Refill and place the Generator back into
operation in accordance with steps OP1,
OP12 and OP13 in the OPERATING
PROCEDURES Section.