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Centrifugal Pumps Design and Application 2nd ed - Val S. Lobanoff, Robert R. Ross (Butterworth-Heinemann, 1992)

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Vertical <strong>Pumps</strong> 123<br />

• Loading pumps in underground caverns us<strong>ed</strong> for storing petroleum<br />

products. The pump is mount<strong>ed</strong> in a caisson.<br />

• Dewatering pumps in mines. The pump is mount<strong>ed</strong> in a mine shaft,<br />

Water Well <strong>Pumps</strong><br />

This is the most common application <strong>and</strong> covers a broad range of services<br />

such as municipal water supply, irrigation service, <strong>and</strong> industrial<br />

service water. For settings down to 400 feet, a line shaft construction<br />

with a surface mount<strong>ed</strong> driver is normally us<strong>ed</strong>. It should be not<strong>ed</strong> that<br />

line shaft construction requires that the well be straight, so that the column<br />

shaft bearings can be kept in alignment. The well must be check<strong>ed</strong><br />

for mis purpose prior to pump installation. For settings beyond 400 feet,<br />

<strong>and</strong> where electric power is available, the close-coupl<strong>ed</strong> submersible unit<br />

is usually the most cost-effective <strong>and</strong> also the most reliable. The closecoupl<strong>ed</strong><br />

design often permits running at higher rotative spe<strong>ed</strong>s. With<br />

elimination of line shafting <strong>and</strong> corresponding bearings, well straightness<br />

is not as important. However, the well should be "cag<strong>ed</strong>" (check<strong>ed</strong> with<br />

a dummy pump/motor assembly) prior to pump installation to make sure<br />

the unit will not bind in "dog legs."<br />

Inctfrte-Mount<strong>ed</strong> <strong>Pumps</strong><br />

The cost of excavating <strong>and</strong> providing an adequate intake <strong>and</strong> mounting<br />

structure for vertical pumps on lakes <strong>and</strong> river banks can be substantial,<br />

particularly where large fluctuations in water level require high structures.<br />

A less costly installation may be achiev<strong>ed</strong> by mounting vertical<br />

pumps on an incline on a lake or river bank, as shown in Figure 9-10.<br />

The pump is mount<strong>ed</strong> inside a pipe or in a trough, permanently anchor<strong>ed</strong><br />

on piers along the bank with the bowl assembly at a sufficient depth to<br />

provide adequate submergence. The pump can either be of the line shaft<br />

type with an electric motor drive or close coupl<strong>ed</strong> to a submersible motor,<br />

in which case both the pump <strong>and</strong> motor are mount<strong>ed</strong> in the pipe or on the<br />

trough,<br />

Cavern <strong>Pumps</strong><br />

For ecological as well as safety <strong>and</strong> economic reasons, petroleum products,<br />

ranging from propane to crude oil, are often stor<strong>ed</strong> in natural or manmade<br />

caverns rather than in large surface tanks [7]. ^fell type pumps, most<br />

commonly driven by submersible motors, are us<strong>ed</strong> for unloading the cavern<br />

before the product is further transport<strong>ed</strong> by pipeline or ship. The pumps are<br />

usually mount<strong>ed</strong> in a caisson, which is seal<strong>ed</strong> at the top ami terminates near

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