DemoQuesto sistema è in fase dimostrativa e non è un servizio operativo. I dati possono essere cancellati in qualsiasi momento; ordini, preventivi e pagamenti non hanno effetto reale. Non inserire dati reali di carte né informazioni personali sensibili.

Torna alla base di conoscenza

Norma

56 visualizzazioni

Set Pressure vs. Cold Differential Test Pressure — A Field Guide

set pressureCDTPback pressurebench test

The short answer

Cold differential test pressure (CDTP) compensates the bench set point for the temperature and back-pressure the valve will see in service.

Rules of thumb

For conventional valves, add the superimposed back pressure to the desired set pressure.
Correct for temperature when service exceeds 120 C, using the manufacturer chart.
Balanced-bellows valves already negate most back-pressure effects — check the datasheet first.

Common mistakes

Applying CDTP to pilot-operated valves without checking the pilot dome rating, and forgetting that CDTP changes when the process conditions change.