Preventing Differential Sticking with Gilsonite

Differential sticking happens when the drill string is pressed into a thick filter cake by the pressure difference between the mud column and a permeable formation. It is one of the most common causes of stuck pipe.

Root causes

• Thick, sticky filter cake
• High overbalance
• Permeable formations
• Pipe left stationary

How gilsonite helps

Gilsonite reduces fluid loss and creates a thin, tough, low-permeability filter cake. A thinner cake means less contact area between pipe and wall. Gilsonite also adds lubricity to the cake surface.

Best practices

• Keep HPHT fluid loss low with gilsonite and proper bridging materials.
• Minimize overbalance where safe.
• Keep the pipe moving.
• Use spotting fluids promptly if sticking occurs.

Dosage

4–8 lb/bbl through permeable sections.

Risk factors table

Emergency response

If the pipe becomes stuck, reduce overbalance if safe, apply torque and jarring, and spot a release agent. Prevention is far cheaper than recovery.

Our drilling fluid grade gilsonite is designed for this application. Also read reducing torque and drag.