Pump Intel

Pump performance curve classification

Framework for mapping pump types to performance-curve families and presentation axes—aligned with the pump hierarchy page and industry references (Hydraulic Institute, DOE pump fundamentals).

Pump hierarchy & animations Types & vendors Learning & training

Industry corroboration

The hierarchy and curve behavior below match widely published pump fundamentals. Key external references:

Hydraulic Institute — pump types: rotodynamic (centrifugal, axial, mixed flow) vs positive displacement (rotary and reciprocating).
Hydraulic Institute — pump curves: rotodynamic curves plot head vs flow at speed; operating point set by system interaction.
Pumps & Systems — centrifugal vs PD: centrifugal flow varies with system head; PD delivers nearly constant flow vs differential pressure (with slip at high pressure).
DOE — Fundamentals of Pumps: PD ideal curve is a vertical line on head vs flow; real PD shows slippage as discharge pressure rises.

Validated

Dynamic branch = HI rotodynamic (centrifugal, axial, mixed flow).
PD → Rotary / Reciprocating split; multiple vs single rotor grouping per HI-style nomenclature.
AODD as reciprocating diaphragm, air-operated (fluid-operated actuation).
Rotodynamic Head_Flow presentation; PD rotary RPM_Flow_DeltaP grouping.
AODD curves use supply air pressure (not RPM) as the primary driver—distinct from rotary PD.

Caveats (implementation notes)

PD flow is not perfectly flat—slip reduces flow at higher ΔP (especially rotary gear pumps).
Viscosity shifts both rotodynamic and PD curves (see ANSI/HI 9.6.7 for rotodynamic viscosity correction).
EDD and expanded AODD detail are Pump Intel extensions beyond Pump School Figure 1.
“Head” vs “ΔP” on AODD OEM charts varies by vendor; store both where needed.
Separate Power Piston vs Power Plunger curve rows is a database convenience—field curves may share the same stroke axes.

Pump hierarchy

Pumps
├── Positive Displacement (PD)
│   ├── Rotary
│   │   ├── Multiple Rotor
│   │   │   ├── External Gear
│   │   │   ├── Internal Gear
│   │   │   ├── Gerotor
│   │   │   ├── Lobe
│   │   │   ├── Circumferential Piston
│   │   │   └── Screw (Multiple Rotor)
│   │   └── Single Rotor
│   │       ├── Vane
│   │       ├── Piston (Single Rotor)
│   │       ├── Progressing Cavity
│   │       ├── Screw (Single Rotor)
│   │       └── Peristaltic
│   └── Reciprocating
│       ├── Diaphragm
│       │   ├── Simplex
│       │   ├── Multiplex
│       │   ├── Fluid Operated
│       │   │   ├── Air Operated (AODD)
│       │   │   └── Hydraulic Operated
│       │   ├── EDD
│       │   └── Mechanically Operated
│       └── Piston / Plunger
│           ├── Power
│           │   ├── Single-Acting
│           │   ├── Double-Acting
│           │   ├── Simplex
│           │   ├── Duplex
│           │   ├── Triplex
│           │   └── Multiplex
│           └── Steam Double-Acting
│               ├── Simplex
│               └── Duplex
└── Dynamic
    ├── Centrifugal
    ├── Axial Flow
    └── Mixed Flow

Database structure

Suggested relational layers for curve cataloging:

pump_family: Top split: PD or Dynamic.
pump_category: e.g. Rotary, Reciprocating.
pump_type: Leaf type from hierarchy (External Gear, AODD, Centrifugal, …).
curve_family: Standardized grouping for chart logic (see below).
curve_presentation: Axis template for stored curves (RPM_Flow_DeltaP, Head_Flow, …).

Curve family assignments

Positive displacement

External Gear, Internal Gear, Gerotor, Lobe
Circumferential Piston, Screw (Multiple Rotor)
Vane, Piston (Single Rotor), Progressing Cavity, Screw (Single Rotor), Peristaltic
Simplex Diaphragm, Multiplex Diaphragm
Air Operated (AODD), Hydraulic Operated Diaphragm, EDD, Mechanically Operated Diaphragm
Power Piston, Power Plunger
Steam Double-Acting Piston, Steam Double-Acting Plunger

Dynamic

Centrifugal
Axial Flow
Mixed Flow

Curve presentation types

curve_presentation defines which independent variables are plotted for each pump type.

Pump type	`curve_presentation`
External Gear, Internal Gear, Gerotor, Lobe, Circumferential Piston, Screw (Multiple Rotor)	`RPM_Flow_DeltaP`
Vane, Piston (Single Rotor), Progressing Cavity, Screw (Single Rotor), Peristaltic	`RPM_Flow_DeltaP`
Simplex Diaphragm, Multiplex Diaphragm	`Stroke_Flow_DeltaP`
Air Operated (AODD)	`AirPressure_Flow_Head`
Hydraulic Operated Diaphragm, Mechanically Operated Diaphragm	`Stroke_Flow_DeltaP`
EDD	`Speed_Flow_Head`
Power Piston, Power Plunger	`Stroke_Flow_DeltaP`
Steam Double-Acting Piston, Steam Double-Acting Plunger	`Stroke_Flow_DeltaP`
Centrifugal, Axial Flow, Mixed Flow	`Head_Flow`

Performance curve behavior

Positive displacement

Flow stays nearly constant as discharge pressure rises (ideal: vertical line on head vs flow).
Flow is driven mainly by speed, stroke rate, or displacement per cycle.
Developed pressure is set by the system, not by throttling the pump curve like a centrifugal.
Real curves show slip—flow falls slightly at high ΔP as fluid leaks from discharge to suction.
AODD: supply air pressure sets energy input; flow vs discharge head is relatively flat until stall—use AirPressure_Flow_Head, not RPM.

Dynamic (rotodynamic)

Flow decreases as head increases—downsloping pump curve on a head vs flow chart.
Operating point = intersection of pump curve and system curve.
Speed changes shift the curve (affinity rules); impeller trim shifts centrifugal curves.
Efficiency, power, and NPSHR are typically plotted vs flow on OEM centrifugal charts (HI standard presentation).

Standardized curve groups

Roll-up families for shared chart components and validation rules:

PD_Rotary_RPM: Gear, Gerotor, Lobe, Circumferential Piston, Screw, Vane, Progressing Cavity, Peristaltic — speed-based rotary PD.
PD_Reciprocating_Stroke: Diaphragm (except air-driven), Piston, Plunger — stroke/cycle-based reciprocating PD.
PD_Air_Driven: Air Operated Diaphragm (AODD) — see Sandpiper selector, selection tools.
Dynamic_Head_Flow: Centrifugal, Axial Flow, Mixed Flow — rotodynamic head vs flow at speed.