Explosion

(of a Boiler). The sudden rending of the shell by steam pre ure, whether owing to faulty construction, wear and tear, or negligence. Accident through too great pre ure of steam; or through exce ive incrustation. f Insufficiency of water; exposes the heating surface to contact with the cold feed-water, when an immediate contraction of the parts takes place, and an explosion often follows. 2nd Too great pre ure of steam; can arise from defective action of safety-valves and steam-gauges 3rd Exce ive incrustation on the furnace-crown and other parts of the heating surface, obstructs the conduction of heat from the furnace to the water, thus causing the parts coated by it to become red hot, in consequence of which they collapse. This collapsing of the iron or steel causes the fracturing of the crust, permitting the water to come into sudden contact with the overheated metal, which is then often ruptured with explosive force.