Page 66 - Centrifugal Pumps Design and Application

General Pump Design 49

designed and test checked. The other sizes that follow specific speed
lines can be factored up and their performance accurately predicted,
designed and test checked. The other sizes that follow specific speed
lines can be factored up as described in Chapter 2 and their performance
accurately predicted.
After the hydraulic performance range chart is complete, the designer
should check the mechanical requirements as outlined by the applicable
industrial specification.
If a complete line is being designed, the following mechanical features
should be checked.

• Shaft sizes
• Bearing arrangements
• Stuffing box design
• Bolting for maximum pressures
• Suction pressures
• Pump axial and radial balance
• Bed plates, motor supports, etc.
• Gasketing
• Lubrication
The standardization and the use of existing parts should be considered
at this time; however hydraulic performance should never be sacrificed
for mechanical or cost reasons. If sacrifice becomes necessary, adjust
pump hydraulics accordingly. Mechanical design features will be cov-
ered in other chapters.