Frictional pressure is pressure loss acting in the opposite direction of fluid flow and today we will look into each component in pressure therefore you will get clearer picture about the frictional pressure in drilling system.

Let take a look at the simple diagram below.

A mud pump creates power to move drilling fluid from point **A** to **C** and the frictional pressure or pressure loss is the amount of pressure required to transfer fluid.

Pump pressure is 2,000 psi at the starting point (“A”) and at the end point (“C”), pressure is 0 psi. This tells you that you need 2,000 psi to overcome the frictional pressure in order to move the fluid from point “A” to point “C”.

**“Differential pressure between two points in the system is pressure loss while fluid is moved from one to another point.”**