Page 219 - Centrifugal Pumps Design and Application

High Speed Pumps 193

Figure 11-9. Radial load trends.

ures along with the letters S, D, and C, indicating shutoff, design, and
cutoff flow rates. The concentric bowl side load increases continuously
with flow and is always oriented in the general direction of the discharge
throat. The volute radial load virtually vanishes at design flow, but
undergoes about a 180° reversal in direction over the full flow range.
These considerations are significant when fluid film bearings are used
and the lube feed spreader groove location must not encroach into the
bearing load zones.