For what conditions the tubes and fittings of a boiler needs to be inspected

Tubes should be inspected externally for the following conditions:

a.   Sagging or bowing.

b.   Bulging.

c.   Oxidation or scaling.

d.   Cracking or splitting.

e.   External corrosion.

f.    External deposits.

g.   External pitting.

h.   Leaking rolls.

Fittings should be inspected externally for the following conditions:

a.   Damage or distortion.

b.   Corrosion.