N 10122 



Figure 8.- 



-Plastic spray equipment with small-type compressor used in experimental 

 work for one-man operation. 



pressor rated at a minimum of 30 cubic feet per minute at approximately 90 

 pounds pressure. 



It is to be recognized that in a sealing operation the compressor runs for approxi- 

 mately 8 hours each day during the entire period of application. Small compres- 

 sors are, as a rule, not constructed for continuous use; therefore if the smaller unit 

 is used, it must be of the heavy-duty type. The smaller compressor shown in 

 figure 8 was used in experimental work in Norfolk, Va., and was found to be 

 inadequate. The length of hose required further reduced the efficiency of this 

 unit and, accordingly, it is recommended that a heavier type of compressor than 

 the one shown in the illustration be used. 



Because of the viscous nature of sprayable plastic, it requires an industrial type 

 of spray gun having a delivery rate of about 22 cubic feet per minute. It is 

 believed that a compressor rated at 100 pounds and delivering approximately 60 

 cubic feet per minute would be desirable. The cost of this equipment, based on 

 prices prevailing at the time of the experimental work, was approximately $1,400. 



On a smaller operation of this kind, three spray guns are required and one-half 

 of the number of the other items shown in the list on page 13. 



14 



