173

aDouble-suction.

aDouble-suction.

Actually the downsurge would be less than this because of the effects of inertia and friction, which have been neglected. If this pump were stopped suddenly by a shaft seizure or by an obstruction fouling the impeller, Column 4 of Table 9 shows the downsurge to be (-0.55)(100) — 4 = -59 feet (-18 m), which would cause water column separation and, probably, subsequent water hammer. If, following power failure, the pump were allowed to operate as a no-load turbine under the full normal pump head, Column 8 of Table 9 shows the runaway speed would be 1.14 times the normal pump speed. The steady-state runaway speed usually would be less than this because the effective head would be decreased by friction, but higher speeds would be reached during the transient preceding steady-state operation. Column 8 shows that runaway speeds increase with increasing specific speed.

Survival Treasure

Survival Treasure

This is a collection of 3 guides all about survival. Within this collection you find the following titles: Outdoor Survival Skills, Survival Basics and The Wilderness Survival Guide.

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