Issue 6 and Volume 101.

QUESTIONS and ANSWERS Static Head To the Editor: An engine is pumping through 1,050 feet of 2 1/2-inch hose equipped with 1 1/8-inuch nozzle. Hydrant pressure is 115 pounds and there is a drop of approximately eight feet from the hydrant to the fire. What will be the nozzle pressure? E. L. E. Answer: First change the static head of 8 feet to pounds per square inch pressure. This is done by multiplying the 8 by .434, giving us 3.5 pounds approximately. Then the corrected hydrant pressure will be 115 + 3.5 or 118.5 pounds. Nozzle pressure = engine pressure / (1.1 + KL) Engine pressure is 118.5 pounds; K, which is a factor depending upon hose and nozzle diameters is, for 1 1/8-inch nozzle on 2 1/2-inch hose, .167; L, which is the number of 50-foot lengths of hose in the line is 21. Then N. P. = 118.5…

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