INSTALLATION, OPERATION AND MAINTENANCE MANUAL
Easco Boiler Corp 1175 Leggett Ave Bronx, NY 1047 T: 718.378.3000 F: 718.378.4560 [email protected] easco.com
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substances which may have entered the Boiler. Any evidence of oil should be noted
carefully, as a small amount is dangerous, and immediate steps should be taken to
prevent the entrance of any more oil into the Boiler.
h) Corrosion, Grooving – Corrosion along or immediately adjacent to a seam is more
serious than a similar amount of corrosion in the solid plate away from the seams.
Grooving and cracks along longitudinal seams are especially significant, as they are
likely to occur when the material is highly stressed. Severe corrosion is likely to occur
at points where the circulation of water is poor; such places should be examined very
carefully. For the purpose of estimating the effect of corrosion or other defects upon the
strength of a shell, comparison should be made with the efficiency of the longitudinal
joint of the same boiler, the strength of which is usually less than that of the solid sheet.
i) Manholes and Other Openings – The manhole(s) and other reinforcing plates, as
well as nozzles and other connections flanged or screwed into the Boiler, should be
examined internally, as well as externally, to see that they are not cracked or deformed.
Wherever possible, observation should be made from the inside of the Boiler as to the
thoroughness with which its pipe connections are made to the Boiler. All openings to
external attachments, such as connections to a low water cut-off and openings to
safety/safety relief valves should be examined to see it they are free from obstructions.
j) Fireside Surfaces – Bulging, Blistering, Leaks – Particular attention should be given
to the plate or tube surface exposed to fire. The inspector should observe whether any
part of the Boiler has become deformed during operation by bulging or blistering. If
bulges or blisters appear, it could seriously weaken the plate or tube, especially when
water is leaking from such a defect, the Boiler should be discontinued from service
until the defective part or parts have received proper repairs. Care should be made
to detect leakage from any part of the boiler structure, particularly in the vicinity of
seams and tube ends. Firetubes sometimes blister but rarely collapse; the inspector
should examine the tubes for such defect. If bulges or blisters are found, they should be
examined by an authorized inspector.
k) Testing Stay-bolts – The inspector should test stay-bolts by tapping one end of
each with a hammer and, when practicable, a hammer or other heavy tool should be
held at the opposite end to the test more effective.
l) Tube Defects - Tubes in horizontal fire tube Boilers deteriorate more rapidly at the ends
toward the fire, and they should be carefully tapped with a light hammer on their outer
surface to ascertain if there has been a significant reduction in thickness. They should
be reached, as far as possible, either through the hand holes, if any, or inspected at the
ends. The surface of tubes should be carefully examined to detect bulges or cracks or any
evidence of defective welds. Where there is a strong draft the tubes may become thinned
by erosion produced by the impingement of particles of fuel and ash. A leak from a tube
frequently causes a corrosive action on a number of tubes in its immediate vicinity.
m) Ligaments between Tube Holes – The ligaments between tube holes in the heads
of all firetube Boilers and in shells of water tube boilers should be examined. If leakage
