Figure 1-33.Wire bristle brush for cleaning large tubes.
Figure 1-34.Brush refill.
material around the hose to show how far the tube cleaner
can be inserted without having the brush protrude beyond
the far end of the tube. Then remove the cleaner from the
tube. Remember that the tubes in each row are the same
length; however, the tube lengths vary from row to row.
Therefore, separate markings have to be made on the hose
for each row of tubes.
After the hose has been marked, insert the brush in
the tube and turn on the air to start the brush rotating. Pass
the brush SLOWLY along the length of the tube until the
identifying mark has been reached. Then slowly draw the
brush back. withdrawing the cleaner from the tube. You
do not have to shut off the air to the tube cleaner each time
the cleaner is withdrawn from the tube. However, be sure
to steady the brush assembly with your hand to keep the
cleaner from whipping. Allowing the brush to whip at
either end of the tube is the most common cause of broken
Establish a new mark for the next row and proceed
with the cleaning. Make as many passes as necessary
through each tube to ensure adequate cleaning. Be
careful not to stop the tube cleaner in any one place in the
tube, as the continued rotation of the brush in one place
might damage the tube. Be careful, also, to see that the
brush and the flexible shaft do not protrude from the other
end of the tube, as this may result in a broken shaft.
The tube is most easily cleaned from the steam drum.
However, some rows of tubes are not accessible from the
steam drum and must be cleaned from the water drum or
header. The lower ends of ALL tubes must be cleaned
from the water drum or header. You may also find tubes
bent so that brushes cannot be forced around the bend
without breaking the tube cleaner. These tubes must be
cleaned from both ends. Tube cleaners must be kept in
good operating condition. The rotor and blades of the air
motor should be kept clean and well lubricated. The hose
connections should be kept tight and free from leaks. The
flexible shafts should be inspected frequently and
renewed when they show signs of wear or damage. When
the brushes become too worn to work efficiently, a new
set of brush refills should be inserted into the brush body.
Store tube cleaners in a clean, dry container.
After all tubes, drums, and headers have been
cleaned and after all tools and equipment have been
removed from the watersides, blow through the tubes
with air; then wash out the drums, tubes, and headers with
fresh water. Ensure all dirt is removed from the handhold
seats. Then examine the seats for scars, pits, or other
defects that might cause leakage. All bottom blow,
header blow, and test cock valves should be inspected and
repaired under the manufacturers instructions during
each waterside cleaning.
After washing, thoroughly dry out the boiler
Inspect the watersides to determine the
condition of the metal to see if the cleaning was
satisfactory. Also, inspect the boiler to be sure that all the
parts are tight. Be sure that all openings between drums
and gauge glasses, blow valves, and safety valves are
clean and free of foreign matter. These openings are
In most cases. mechanical cleaning is the preferred
method for cleaning watersides. Chemical (acid)
cleaning requires special authorization. since it requires
elaborate and costly equipment and rather extensive
SAFETY precautions. However, you may have to use the
chemical method, so a limited discussion on it is given
Inhibited acid cleaning is used to remove mill scale
from the watersides of new or recently serviced boilers.
When compared with mechanical cleaning, acid cleaning
of boilers has the following advantages:
Less outage time is required.