Page:Popular Science Monthly Volume 92.djvu/280

 264

��Popular Science Monthly

���top of the tower by natural draft, just as smoke is drawn out of the top of an ordinary- brick chimney.

��B'

��Cold spray dropping down to the cold water sump or reservoir at the extreme bottom of the wooden tower

��Cooling Engine Water in Wooden Chimneys

HUGE wooden chimneys now serve to cool the water from powerplant steam engines, especially from stea... turbines. Usually fans or blowers are installed — but not in these cheap towers. Think what this means in keeping down cost. There are no moving parts of ma- chinery to be inspected and overhauled at regular periods in order to keep them in good con- dition.

The water is cooled by leading it to a horizontal header in the center, from which it is allowed to drop upon a checkerwork of iron pipes and lateral gutters. Thus it is broken up into a fine spray which ultimately drops to the cold water reservoir at the extreme bottom of the tower. Here the hot water is further cooled by the passage of cold air entering on either side of the tower bottom and forced up and out the

��Prolonging the Life of a

Motor by Protecting

Its Insulation

ROADLY speaking, a motor may be divided into two parts — the wind- ings, through which the cur- rent flows, and the part into which the current must not be allowed to leak. The windings, which may be called the circulation system of the motor, are analogous to the arteries of the human mechanism, and the insula- tion to the walls of the arteries. To continue the simile, if the insulation is cut or seriously impaired, there is danger of such an amount of current being wasted as to destroy the life or usefulness of the motor, just as the severing of an artery may cut short a man's three score years and ten.

Among the practices which are responsible for the weaken- ing or destruction of the insula- tion are prying into windings with metal instruments, pound- ing or bumping the windings, storing the motors in damp places without protecting them from the dampness, which may proceed from a leak or from escaping steam, or placing them in an at- mosphere laden with acid fumes or minute flying par- ticles of metal.

Periodic atten- tion to the insula- tion as well as to the other parts of mechanism will

XT ^. J u- be amply repaid. Acces- How the wooden chimney .,, .1 u t works. No expensive fans Slble parts should fre- er blowers are needed quently be wiped clean.

���Water inlet

��Cooling stacks

��Air inlet

��Suction pipe the

�� �