Diesel engine fire pump as an important tool for fire fighting and rescue, rescue of life and property, must have a faster reaction rate, especially the diversion time must be very short, so as to reduce the loss to the maximum extent. The time of fire pump water has very strict requirements, the flow rate of less than 50 L/s of the pump, the diversion time is no more than 35 s; flow rate of 80 L/s or more of the pump, water diversion time is not more than 80s .
The formula is deduced in accordance with the standard atmospheric pressure, when the test pressure is not 1 standard atmospheric pressure, to deal with the estimation formula for correction. When the estimation formula is highly variable within the scope of 7-D/2,7 and calculation of diversion time does not apply the formula, however, due to the (7-D/2) to (7 height is relatively small. And at the same time, diesel fire pump also has certain exhaust effect, so the course of time is very short, the total calculation has little effect on the results. Analysis of factors affecting fire pump water time obtained the relationship between diversion and diversion pump flow, diesel fire pump water mathematical model is established, deduces the diesel fire pump water diversion time estimation formula.
