Page:Popular Science Monthly Volume 92.djvu/117

Like Water from a Hose

A method of Spraying Asphalt by hand — good for tight places

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A NEW type of nozzle, made by a Boston manufacturer, is designed for spraying hot asphalt-binder in road construction or on sidewalks, where the use of a large motor-truck outfit would be unsuitable. The hot fluid is uniformly . sprayed at a tempera- ture of 350 degrees Fahrenheit and at a pressure of forty pounds per square inch. The high pressure causes the asphalt to permeate all the voids between the stone, which it is in- tended to bind. The portability of the ap- paratus makes it possi- ble for this to be accom- plished easily. With a motor-truck it would be almost impossible to reach the corners.

The sprayer can also be used for patching holes in bituminous roads and for applying roof coatings'.

The asphaltic material is heated in the usual manner and put

Unequal density v', across section \

of spray

Central driving jet

Turbine cente rotated by ' force of asphalt

Solid asphalt through center

The nozzle has a turbine cen- ter which controls the density

The asphaltic material is heated and applied un- der pressure from a gaso- line-driven rotary pump

under pressure by means of a, gasoline-driven ro- tary pump. It is then carried to a special noz- zle by means of a hose. The nozzle has a fixed turbine center which disposes of the liquid in such a way that a dense uniform spray is ob- tained. This prevents the material from being too thick in some spots and too thin in others. The turbine in the nozzle is stationary, yet removable, and gives a part of the liquid pass- ing through it a rotary motion. This portion is driven out through the orifice of the nozzle by the central driving jet.

The liquid asphalt is carried to the special nozzle through a hose. The nozzle sends it out in a solid conical formation of equal density across its section

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