Steam generators, as they are exposed to more or less of trying service in steam production, develop almost an unending number and variety of defects.

When a boiler is new and first set up it is supposed to be clean, inside and out, but even one day’s service changes its condition; sediment has collected within and soot and ashes without.

Unlike animals and plants they have no recuperative powers of their own—whenever they become weakened at any point the natural course of the defect is to become continually worse.

In nothing can an engineer better show his true fitness than in the treatment of the beginnings of defects as they show themselves by well-known signs of distress, such as leaks of water about the tube ends, and in the boiler below the water line, or escaping steam above it. In more serious cases, the professional services of a skillful and honest boiler maker is the best for the occasion.

In a recent report given in by the Inspectors the following list of defects in boilers coming under their observation was reported. The items indicate the nature of the natural decay to which steam boilers in active use are exposed. The added column under the heading of “dangerous” carries its own lesson, urging the importance of vigilance and skill on the part of the engineer in charge.

Nature of Defects.Whole Number.Dangerous.

Cases of deposit of sediment

419 36

Cases of incrustation and scale

596 44

Cases of internal grooving

25 16

Cases of internal corrosion

139 21

Cases of external corrosion

347 114

Broken and loose braces and stays

83 50

Settings defective

129 14

Furnaces out of shape

171 14

Fractured plates

181 84

Burned plates

93 31

Blistered plates

232 22

Cases of defective riveting

306 34

Defective heads

36 20

Serious leakage around tube ends

549 57

Serious leakage at seams

214 53

Defective water gauges

128 14

Defective blow-offs

45 9

Cases of deficiency of water

9 4

Safety-valves overloaded

22 7

Safety-valves defective in construction

41 16

Pressure-gauges defective

211 29

Boiler without pressure-gauges

3 0

This list covers nearly, if not all, the points of danger against which the vigilance of both engineer and fireman should be continually on guard; and is worth constant study until thoroughly memorized.

Note.

Probably one-quarter, if not one-third, of all boiler-work is done in the way of repairs, hence the advice of men who have had long experience in the trade is the one safe thing to follow for the avoidance of danger and greater losses, and for the best results the united opinion of 1, the engineer, experienced in his own boiler and 2, the boiler-maker with his wider observation and 3, the owner of the steam plant, all of whom are most interested.