Duty path
Duty · Q — · —

Valve sizing calculator

Size an isolation or control valve from the line on a Kenyan or East African duty. The nine-field enquiry rewrites from the sheet.

Enquiry document

Specification request

Living sheet · rewritten from calculator

Auto-composed from the duty above

These nine fields are not a blank form. They rewrite as you size — function, medium, pressure and the computed Cv become the enquiry. Edit a line if you need to; otherwise send it as composed.

1 Function
2 Design basis
3 Process medium
4 Family shortlist
5 Seat
6 Connections
7 Materials
8 Certification
9 Maintenance
Email this spec to yourself Send a copy to our team

This sheet is an estimate for enquiry. It is not a certified OEM sizing and it does not name a steel grade. Wrong class / material / seat is the failure described in Choosing industrial valves — function first.

Left pane stays with the tool · Duty is the join key across all six calculators.

Line conditions

Function
Fluid
Units
m³/h
Flow must be greater than zero.
bar g
P1 must be greater than P2.
bar g
P2 plus atmospheric pressure must be greater than zero (absolute).
°C
Liquid specific gravity
SG to air = MW / 28.96. Air = 1. Used for gas only.
bar a · default 0.023 = water at 20°C. Used for liquid choked check.
Nominal bore for velocity. Valve DN is suggested from Cv, not copied from the pipe.
Advanced · FL, xT, critical pressure, site elevation

Assumptions, editable. FL default 0.9 (liquid) · xT default 0.7 (gas and steam) · Pc unknown → Ff = 0.96 (liquid).

If set, Ff ≈ 0.96 − 0.28 √(Pv/Pc). Otherwise Ff = 0.96.
m · converts bar g to bar a. Blank = sea level (1.013 bar a); JKIA 1,624 m ≈ 0.83 bar a.

Example is illustrative only — not a named plant.

Result · live

Enter valid line conditions. P1 > P2, absolute outlet above zero, Q > 0.
— Cv

Kv —

Suggested DN
—
Opening (linear)
—
Pipe velocity
—
Rated Cv @ size
—

Estimate for enquiry, not a certified OEM sizing. Wrong class, material or seat is the failure the article describes. Confirm with manufacturer software and ASME B16.34 at temperature before a purchase order.
Interconnect — Wire navigates the six tools; Split Desk keeps the enquiry visible while you size. Shared Duty object (proxico.duty.v1) carries Q, head/ΔP, T, medium, elevation.

Wire map Duty plumbing · 6 tools

Duty · —

Valve sizing

Q—
ΔP—
Cv—

Chem check

Medium—
Path—

Pump duty

Q—
H—
kW—

Atm head

z—
Hatm—

Diesel vs grid

EnergyKES/yr

Suction lift

DerateHatm
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