Pump Selection, Evaluation and Specifications:
Objective, independent engineering consulting services specializing in rotodynamic (centrifugal, mixed flow and axial flow) pumping equipment.
The short-term and long-term consequences of proper pump selection and “getting the engineering right” are significant. At stake are on-time delivery of the machinery package, trouble-free installation and start-up, reliable pump operation and optimal energy usage.
Specified pumps often deserve special attention due to one or more of the following:
- high level of input power or energy consumption
- physical size or space limitations
- hazardous or flammable liquids
- high temperatures or pressures
- special materials of construction
- entrained gases or solids
- consequences of failure
- wide variations in operating conditions or changing operating conditions over time
- variable speed operation
- transient conditions
- piping and intake conditions
- low Net Positive Suction Head Available
- new or modified designs
For example, the appropriate margin for NPSH Available above the NPSH Required is a system and pump interface that can affect operational stability of the process and pump reliability. On high suction energy applications, the intake conditions, local internal velocities, impeller flow incidence, fluid properties, material properties and other factors affect the severity of cavitation and component erosion life. An independent review of critical service pumping applications can help resolve such technical issues early on before unanticipated issues arise on test or in the field.
Evaluation of essential pump selection parameters including overall mechanical configuration and arrangement, staging, drive train and driver type, rotative speed, net positive suction head, nozzle orientation, materials of construction, shafting, thrust compensation, couplings, bearings, seals, etc.
Evaluation of pump and system performance including:
- system total head versus rate of flow
- head versus flow (H-Q) curve slope
- H-Q stability of single and multiple pump operation
- pump minimum flow
- viscous effects
- effects of wear and parasitic losses
- input power
- net positive suction head (NPSH) available and required
- minimum submergence and vortexing countermeasures
Review/evaluation of reverse flow, reverse speed, locked or free rotor modes of operation
Pumping system optimization
Assessment of equipment foundations, baseplates, mounting, installation and alignment
Review of piping and nozzle loads
Assessment of component cavitation erosion and impeller life
Review of pump inlet piping and open pit intake settings
Design review, failure mode and effects analysis (FMEA), and value engineering (VE)
Evaluation of pump test piping, control valves, hardware fixtures, and instrumentation
Selection and evaluation of hydraulic power recovery turbines, liquid expanders, and small hydro units
Contact us now so we can help you with your pump engineering needs!