About

Last updated: 30 August 2026 · Ontario, Canada

CurvePoint is a pump system and curve analysis tool. Build a system curve from fluid, static, and piping data, overlay a manufacturer performance sheet, and export an engineering report with the duty point, friction, NPSH, and a simple P&ID sketch.

Reports, sketches, and overlays are for engineering review. They are not sealed calculations or a substitute for a licensed professional engineer. Always confirm inputs and results against manufacturer data and applicable codes.

Who it is for

Application specialists, inside sales, and distributors sizing centrifugal pumps — plus municipal, industrial, and contractor engineers who need a defensible duty point before quoting or issuing a submittal. Typical work: self-priming lift stations, standard end-suction transfers, submersible dewatering, fuel offload, and wastewater.

What it can do

• System curve or specified duty. Calculate H(Q) from the piping system, or enter a known duty when the system is already defined.
• Pump types. Self-priming centrifugal, standard centrifugal, and submersible (no suction line; NPSH omitted).
• Fluids. Water, municipal and industrial wastewater, sludge and paper stock with solids %, petroleum fuels, and custom SG / viscosity.
• Piping. Steel, HDPE, and other materials; lengths, fittings, static suction lift or flooded head, and static discharge head.
• Manufacturer sheets. Search Gorman-Rupp models and curve numbers (SG 1.0 and 0.80 where published), or upload your own PDF/image.
• Digitize the pump curve on the sheet, find the operating intersection, and draw duty-point construction lines.
• NPSH. NPSHa from site altitude, vapor pressure, and total dynamic suction lift; compare to NPSHr from the curve.
• PDF report with duty, friction, total head, NPSH, methods, checks, and a schematic. Free reports carry a preview watermark; CurvePoint Pro removes it.
• Guest use stays on this device. Sign in to save projects, presets, and report contact blocks.

Methodology

• Friction: Darcy–Weisbach with the Churchill (1977) friction factor (laminar through fully rough).
• Fittings: Darby 3-K method. Area-change K from Crane TP-410. Petroleum loading hardware is offered when a fuel fluid is selected.
• System curve: H(Q) = total static + pipe friction + fitting losses on suction and discharge. Pump suction centerline is the datum.
• NPSHa: atmospheric head at site altitude − vapor-pressure head − total dynamic suction lift at duty.
• Viscosity: published water curve below 20 cSt. At or above 20 cSt, ANSI/HI 9.6.7 viscosity correction replaces the OEM H–Q for centrifugal pumps. Above ~3,000 cSt the tool warns that a centrifugal is not appropriate.
• Sludge / paper stock: low solids are treated as water-like. Higher weight-percent solids apply a friction multiplier; the published pump curve is not derated. Lift warnings appear on the Static tab and in the report.

Methods used for a given study are listed on the report. You remain responsible for checking that they fit the application.

How to run a study

1. Choose System Curve (calculate from piping) or Duty Point Only (enter capacity and head).
2. On Type, pick self-priming, standard centrifugal, or submersible. Use a built-in or saved preset if it matches the job.
3. Enter Fluid, Static (lift or flooded suction, discharge head, site altitude), then suction and discharge piping. Submersible studies skip suction and NPSH.
4. On the right, search a Gorman-Rupp curve or upload a sheet. Calibrate axes (flow unit, head/pressure unit, Qmax, Hmax/Pmax). Plot points along the desired pump curve — right click a point to remove it.
5. Review the duty, friction, and NPSH summary. Open Report options for project title, pump labels, and your contact block / logo.
6. Download the PDF. Sign in to save the project. Upgrade to Pro if you need the watermark removed.

Contact

Questions, catalog issues, or account requests: info@curvepoint.io. See also Privacy and Terms.