Gilsonite Asphasol shale inhibitor is a partially water-soluble, sulfonated organic material developed for use in most water-base drilling fluids.Gilsonite Asphasol shale inhibitor contains no surfactants as do most water-dispersible products used in shale-control applications.

Typical Physical Properties

Physical appearance: Black, free-flowing powder
ph (2% solution): 7.5 – 9.5
Solubility in water : Minimum 50% by weight


Gilsonite Asphasol shale inhibitor can be used in most water-base drilling fluids. Gilsonite Asphasol shale inhibitor is a free-flowing powder and can be added directly to the mud system through the mixing hopper. Unlike some shale control additives, it is not necessary to pre-mix the Gilsonite Asphasol inhibitor with oil and it contains no surfactants.

Normal concentrations of Gilsonite Asphasol shale inhibitor range from 2 to 10 lb/bbl
(5.7 to 28.5 kg/m3) for most applications.

Advantages of Gilsonite Asphasol

Contains no surfactants
Premixing is not required
Inhibits swelling and water-wetting of shales
Reduces High-Temperature, High-Pressure (HTHP) fluid loss
Reduces torque and drag
Improves wall cake quality