Rotating Equipment Engineering

Vertical Pump Evaluation Tool

Total differential head at impeller centerline & brake horsepower calculator — verify a vendor's proposed TDH and BHP against the actual system requirement.

Developed by Allan Ronald Dones — Senior Mechanical Engineer, Rotating Equipment Specialist

1Reference & Installation Geometry

Total lift is always added into TDH — it is physical elevation, independent of where the discharge pressure was measured.

Reference point of discharge pressure

Drum-mounted pump (pit slab thickness N/A — A2 becomes mounting flange thickness)

A1 — Nozzle elevation m Top of soleplate to discharge centerline

A2 — Soleplate thickness m

A3 — Pit slab thickness m N/A for drum-mounted pumps

A4 — Pit depth m Bottom of slab to pit floor

A5 — Lowest liquid level m Height of LLL above pit floor

Pipe losses m

2Process Conditions

Discharge pressure basis: measured at discharge nozzle centerline (per tool convention). Adjust input if your gauge reference differs.

Specific gravity, SG

Capacity, Q m³/hr

Suction pressure barg

Discharge pressure barg

Pump efficiency %

iElevation Diagram

Values update live as you enter the geometry above.

✓Calculated Requirement

This is the head and power the system actually demands at the pump impeller.

Head at discharge centerline

0.00m

Total lift

0.00m

Required TDH @ impeller (incl. pipe losses)

0.00m

Water horsepower, WHP

0.00kW

Required BHP

0.00kW

H = ΔP × 10.1972 / SG TDH = H + Lift + Losses WHP = Q·TDH·SG / 367.68 BHP = WHP / Eff

3Vendor Proposal (optional)

Enter the vendor's quoted TDH/BHP to run the sufficiency check.

Vendor's proposed TDH m

Vendor's proposed / rated BHP kW

!Vendor Sufficiency Check

—

TDH — enter vendor value

Waiting for vendor's proposed TDH

—

BHP — enter vendor value

Waiting for vendor's proposed BHP