Page 220 - Boiler_Operators_Handbook,_Second_Edition

Maintenance 205

Any discussion about insulation raises the concern ity a light canvas wrap impregnated with a waterproof
for asbestos bearing insulation contaminating the air in mastic will look better and will last even longer.
the plant. While many facilities have spent the fortune it Outdoors and in areas where the insulation may
costs to remove asbestos bearing insulation others have be struck by people carrying objects such as ladders the
chosen to encapsulate it. If your plant is one of the latter corrugated aluminum jacket with aluminum straps and
then maintenance of that encapsulation has a priority. fasteners is necessary to provide long life. Long runs of
Damage to the cover can occur as a result of normal hot piping pose a special problem, the pipe expands but
operating and maintenance activities, from vibration the insulation doesn’t expand anywhere near as much.
that occurs during normal operation or a plant upset. And the jacket, particularly outside in cold weather, can
A tour to check the integrity of encapsulation should be shrink from its original length. When restoring insula-
performed on a monthly basis. tion on long runs try to compress the existing insulation
When it becomes necessary to gain access to some- as much as possible without crushing it then compress
thing covered by Asbestos insulation you should notify the new material as much as possible when installing it;
your employer so he can have the insulation removed jackets should have a minimum overlap of three inches
unless you have been trained to do it. The laws regard- outdoors and the longitudinal seam should always be
ing asbestos bearing insulation do permit removal of on the side of the piping lapped down to prevent rain
small quantities without all the environmental controls entering the seam. On vertical runs of pipe make certain
required of a major material removal; and you could be any jacketing is lapped to shed water. Do it indoors too
trained to do it. If you are, follow the rules you were because a leak can always spray water, or worse, all over
taught in the class. If not, and you think the contractor the place.
doing the removal is contaminating your air (lots of dust Large flat surfaces require the installation of insu-
blowing around isn’t to be accepted) scream and holler lation studs, wire secured to the surface by stud weld-
because once you’ve breathed it in it’s yours for a life- ing or a special machine that shoots the wire into the
time. Once the work is complete make sure the asbestos surface. The studs hold insulation with special washers
that remains is encapsulated and don’t forget to mention over the stud pressing the insulation against the equip-
its removal, and who did it, in the boiler plant log. ment surface. An impregnated canvas covering or cor-
Whenever insulation is removed for maintenance rugated aluminum jacketing is necessary to protect the
or repair make certain it’s put back or replaced. I, if no- surface of that insulation. Any repair job should return
body else, will have a very low opinion of your mainte- the insulation to a like new condition using one of the
nance practices if I come into the plant and find little bits methods I described.
of insulation missing here and there. Small areas tend What do you do if some insulation gets wet? If it
to become bigger and, after a while, the whole system got so wet that it collapsed it has to be replaced, other-
is bald. Not only is it a waste of energy, it’s hazardous wise let it dry. If it got wet while the pipe was out of ser-
because you could be severely burned. vice and the line contains steam or hot water you should
I was in one plant where I suggested the customer warm the piping up very slowly or you may generate
do something about his insulation for another safety steam under the insulation that will blow it off.
reason. It had received no attention and was literally Damaged or compressed insulation should be re-
falling off the pipes. The hazard was associated with be- placed as part of the annual clean up operation. Where
ing hit on the head by falling insulation! Such instances the damage is repeated some consideration should be
aren’t uncommon and they lead me to recommend you given to installation of better protection of the insula-
never accept an insulation job that consists of nothing tion, consider replacing or covering the jacket with
but stapling up ASJ (All Service Jacket, that white paper heavy galvanized sheet metal thick enough to ward off
like material with the flap that comes on most insula- the damage.
tion) because it won’t last. The staples eventually cor- No, I don’t want to hear the argument that it
rode and fail with the rest of what happens being most doesn’t make any difference if the piping is only used
obvious. during the heating season and it heats the building any-
At the very least piping insulation should be way. The heat lost through lack of insulation is almost
secured with minimum 20-gauge galvanized wire never able to heat the space as intended. It’s almost as
wrapped around it, twisted, and bent back against the weak an argument as the one that I’m always hearing
insulation (to prevent the sharp ends catching or cutting which is “it’s only a little bit.” Little bits become lots
anything or anyone) twice on each section. For longev- when that attitude is taken. “We’re out of that thick-