Definition(s)
Differential Pressure
Difference in pressure between any two points (p1 and p2); measured in “psid”.
Source: API Specification 16A, Specification for Drill-through Equipment, Fourth Edition, April 2017. Global Standards
Differential Pressure
Difference between internal and external pressure or the difference in pressure across a closure mechanism or a packer element.
Source:API SPECIFICATION 19TT, Specification for Downhole Well Test Tools and Related Equipment, First Edition, October 2016. Global Standards
Differential Pressure
The difference in pressure between the hydrostatic head of the drilling fluid in the fluid column, and the pressure exerted by or from the formation at any given depth in the hole. May be positive, zero, or negative with respect to the hydrostatic head.
Source: IADC UBO / MPD Glossary, December 2011. Global Standards