SPRAYING 



251 



15. A good type 

 of nozzle 



more than 24 meshes to the inch is not strong enough to with- 

 stand rough usage, and the fine mesh fills up with sediment and 

 is hard to clean. A strainer of some kind is usually placed on the 

 suction pipe, or suction hose, but some machines are equipped 

 with a metal box or well, attached permanently to the bottom of 

 the supply tank, in which a simple, easily 

 cleaned strainer may be inclosed, thus per- 

 mitting the tank to be drained completely. 

 These wells are furnished with only a few 

 makes of machines. 



Hose. Suction hose that is at least 1 inch 

 in diameter should be used with large spray 

 outfits. Plenty of good hose, piping, cut-offs, 

 hose connections and bands, rod cut-offs, and 

 other necessary accessories should be at hand. The high pressures 

 used in spraying with modern power spraying-machines make 

 the use of strong, heavy-walled hose imperative. Half-inch high- 

 pressure hose of 5-, 6-, or 7-ply construction is generally bought for 

 this purpose. Except where oil sprays are used, the heavier grades 

 usually last enough longer to warrant their purchase. The ^-inch 

 hose, having sufficient strength to withstand 200 pounds' pressure, 

 is not practical, because it is cumbersome and too heavy for the 

 operator to drag around. The f-inch high- 

 pressure hose costs almost as much as the 

 .',-inch hose of similar quality, yet does not 

 have sufficient capacity to supply a cluster 

 of large nozzles without greatly reducing the 

 pressure of each. The hose connections for 

 this size of hose have much smaller openings 

 than the \ -inch size, which partially accounts 

 for the reduction of pressure at the nozzle 

 cap. The lead of hose to the operator on the 



ground should be at least 35 feet, but the lead to the tower can 

 be as short as 12 feet without hampering the operator in hand- 

 ling the spray rod. Barrel pumps and large hand pumps will sel- 

 dom supply more than one lead of hose at a satisfactory working 

 pressure, but two nozzles can be used on the spray rod when one 

 nozzle does not utilize more than half the capacity of the pump. 



Fig. 116. Angle nozzle, 

 a convenient necessity 



