Chapter hvac engineering Fundamentals: Part 1 Introduction

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Chapter Six
Figure 6.28
Closed-coupled end-suction pump. (
Courtesy of ITT Fluid-Handling Divi-
sion, Bell and Gossett
.)
Flexible coupling
(protective housing not shown)
Motor and pump must be carefully
aligned after installation
Figure 6.29
Frame-mounted end-suction pump.
used for most applications. Double-suction pumps are preferred for
larger water volumes over 300 to 400 gal / min, because the purpose of
the double-suction design is to minimize the end thrust due to water
entering the impeller.
6.7.2
Performance curves
A typical pump performance curve (Fig. 6.31) is drawn with coordi-
nates of capacity and head. The curves show the capacity of a specific
pump-casing size and design at a specific speed and with varying im-
Design Procedures: Part 4
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