ENGINEMAN 1 & C
Table 7-2.Natural Circulation Auxiliary Boiler Water Initial Dosage
Factor
X
Boiler Volume
(ounces/
for Chemical
gallon)
Treatment (gallons)
=
Initial Dosage
(ounces)
TSP
0.100
x
=
DSP
0.022
x
=
Initial dosages for several of the auxiliary
boilers are given in table 7-3. The volumes listed
are for the following vessels:
FF-1040, FF-1041, AGFF-1
215 gallons
Other ships having pressure-
fired main boilers
LST- 1179 class
300 gallons
280 gallons
MSOs having cyclotherm
MC-800 boilers
84 gallons
Weigh the necessary amount of chemicals and
place both in the 10-liter safety dispensing bot-
tle. The safety dispensing bottle should be
marked and used For boiler water treatment
chemicals only. Add cold feedwater, cap the
bottle and spout, then shake to dissolve. Inject
the solution into the boiler.
Auxiliary boilers are equipped with a chemical
injection system on a bypass of the feedwater line.
One treatment system schematic and general pro-
cedures for auxiliary boilers are presented in figure
7-3. When you are operating an injection system,
slightly overfill the tank to bleed air out of it. The
over-filling must be minimal; otherwise an ex-
cessive amount of treatment will be discharged to
the bilge. In addition, injection must continue for
at least 10 minutes to ensure that all of the treat-
ment is flushed into the boiler. Upon completion
of the chemical addition, finish filling the boiler
to the lightoff level, or if the boiler has been over-
filled, drain until the proper water level is
reached. A boiler water sample obtained from a
Table 7-3.Chemical Weights For Freshly Filling Some Auxiliary Boilers
Boiler Water Volume for
Chemical Treatment
(gallons)
84
215
280
300
Weight required *TSP
(ounces)
8.5
Weight required **DSP
(ounces)
2
21.5
28
30
4.5
6
6.5
1 gallon = 3.785 liters
1 ounce = 28.35 grams
16 ounces = 1 pound
*TSP - Trisodium Phosphate
**DSP - Disodium Phosphate
7-10