Nozzle Sizing

Chapter from the Vessels & Internals Design Guide.

NAVIGATION

Design P&T Selection	Vessel Sizing	Nozzle Sizing	Level Instruments
Vacuum Vessels	Ceramic Balls	Reference Data

Nozzle Sizing Guide

Nozzle Type	Max Velocity (ft/s)	Typical Size	Line Connection
Feed Inlet	4 - 6	2" - 4"	Top/Side
Vapor Outlet	8 - 12	3" - 6"	Top Center
Liquid Outlet	2 - 4	2" - 3"	Bottom
Reflux Return	2 - 3	1" - 2"	Top/Side
Drain Nozzle	2 - 3	1" - 2"	Bottom Low

Sizing Formula:

Nozzle Area = Flow Rate / Velocity

Diameter = sqrt(4 × Area / π)

Source: Vessels_Internals_Design_Guide_v1.xlsx · sheet “Nozzle Sizing”

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