Pocketbook of Useful Formulæ and Memoranda
for Civil and Mechanical Engineers

Forfatter: Guilford L. Molesworth

Sider: 744

UDK: 600 (093)

Søgning i bogen

Den bedste måde at søge i bogen er ved at downloade PDF'en og søge i den.

Derved får du fremhævet ordene visuelt direkte på billedet af siden.

Download PDF

Digitaliseret bog

Bogens tekst er maskinlæst, så der kan være en del fejl og mangler.

Side af 764 Forrige Næste
283 OF ENGINEERING KOKMUL2E. Pumping Engines. G = Number of gallons to be raised in 24 hours. ~ Number of cube feet raised in 24 hours. — Height in feet to which the water is to be raised. H P = Actual horse-power required __ Gr X Å F X h 1 ~ 4752000 Or 762088 ' 20 per cent, must be added to overcome a fiction, &c., and 50 or 60 per cent, more is usually allowed for contingencies, making a total of 70 or 80 per cent, additional power. To find the Diameter of a Single-acting Pump. G F N D F _________ G = -034 D2 LN. D = L = Length of stroke in feet. Number of galls, to be delivered per minute. Number of cub. ft. to be delivered per minute. A umber of strokes per minute. Diameter of pump in inches •00545 D2 LN. Note.—These formulae give the net diameter of the pump-plunger; it is usual to increase the area of the plunger |th, to allow for leakage, &c. G •034 LN F D = V -00545 LN Useful Numbers foe Pumps. D = Diameter of pump in inches. S = Stroke of pump in inches. D.2 S x '7854 = cubic inches D.2 S x -002833 = gallons. IV S x • 0004545 = cubic feet. I*.2 S x '02833 = lbs. fresh water.