Engineering Calculators
Complete centrifugal-pump hydraulic design calculations covering rated flow, velocities, friction losses, total differential head, system curve, NPSH, power, motor rating, BEP position, minimum flow, shutoff pressure, affinity laws and specific speed. Every calculator includes browser-local calculation history.
Clickable centrifugal pump workflow
Follow the stages in order. Each calculation button opens the existing pump calculator.
Collect fluid density, viscosity, vapor pressure, minimum/normal/maximum flow, source and destination pressures, liquid levels, piping data and operating philosophy.
Output: approved input basis and governing cases.
Apply only the project-approved flow margin where Process has not already issued a rated flow.
Use actual pipe internal diameter and the governing flow case.
Check the suction line using its actual internal diameter and governing flow.
Check the discharge line using its actual internal diameter and governing flow.
Establish the flow regime and pipe-friction coefficient.
Calculate suction and discharge losses separately, including valves, fittings, strainers and entrances.
Include control valve, exchanger, filter, flowmeter and other fixed equipment losses.
Combine elevation, pressure-head difference, suction loss, discharge loss and equipment loss.
Calculate system head over the expected flow range and compare with the vendor pump curve.
Use absolute source and vapor pressures at the governing minimum-level, maximum-temperature and maximum-flow case.
Use the governing density and maximum absorbed power, then select the next project-approved standard motor rating.
Confirm normal and rated points against the vendor preferred and allowable operating regions.
Use the governing minimum continuous stable, minimum thermal and process minimum flows.
Verify casing, flange, discharge piping, valve and downstream equipment pressure ratings.
Apply affinity laws only within their valid range and confirm final performance on manufacturer curves.
Confirm duty, system curve, NPSH, power, motor, minimum-flow protection, shutoff conditions, mechanical configuration and applicable project/API requirements.
Deliverables: calculation note, datasheet, system curve, MR and TBE inputs.
Interactive performance review
Enter representative vendor-curve anchors to visualize pump head, system head, efficiency, absorbed power and NPSH required over the operating range. These generated curves are screening approximations and must be replaced by manufacturer-tested curves for final selection.
Vendor curve data
Import vendor curves from CSV or type them into a table, compare pump alternatives on the same charts, change each curve's colour, and export the combined dataset as CSV.
pump,flow,head,efficiency,power,npshr,flow_unit,head_unit,power_unit. Required: pump, flow, head. Optional performance columns may be left blank.Preliminary pump configuration and applicable industry standard. Final selection requires vendor confirmation and engineering review.
Positive displacement pump workflow
Enter the duty and fluid properties to obtain a pump-family shortlist with reasons. This is a transparent qualitative screening tool, not a vendor model selector or design approval.
Rule order: metering objective; dry-running requirement; abrasive/solids duty; hygienic or shear-sensitive service; clean lubricating service; otherwise a multi-family shortlist. No universal pressure, temperature, flow, viscosity or particle-size capability limits are assumed. Numerical values define the duty and review checklist, not certified family capability. Density and viscosity are also used to calculate kinematic viscosity. No confidence percentage or model guarantee is implied.