Home > KOSUN News >

Main Drilling Fluid Types in the Chinese Market (I)

Sep 25, 2019

1) Solids-free non-dispersed polymer drilling fluid
Basic components: polyacrylamide or multiple vinyl copolymer flocculant, inorganic salt, etc.
Features: flocculant can effectively flocculate cuttings generated in the drilling process.

2) Anionic polymer drilling fluid
Basic components: multiple vinyl copolymers, hydrolyzed polyacrylonitrile, partially hydrolyzed polyacrylamide, etc.
Features: high molecular weight polymer encapsulates clay or cuttings and provides viscosity and shear force required for drilling fluid; medium and low molecular weight polymers can control filtrate loss, viscosity and shear force.

3) Cationic polymer drilling fluid
Basic components: high and low molecular weight cationic polymer, starch, etc.
Features: cationic polymer has the highly powerful ability of stabilizing shale (namely strong absorption and inhibition) and can be used with starch treatment agent to adjust filtrate loss and wall building property.

4) Sulphonated polymer drilling fluid
Basic components: high molecular weight polymer (including anionic, cationic and amphoteric polymers), medium molecular weight polymer filtrate reducer, SMP products, asphalt products, etc.
Features: have a strong inhibitive ability, good wall building property, sealing property, rheological property and thermal stability, as well as low HTHP filtrate loss.

5) Potassium chloride polymer sulfonated drilling fluid
Basic components: KCl, polymer, viscosity reducer, SMP products, sulfonated asphalt products, etc.
Features: the synergistic effect of potassium ion in KCl and polymer can effectively inhibit smectite or irregular illite/smectite interstratified mineral hydration swelling, and prevent the formation collapse.

6) Potassium lime drilling fluid
Features: use potassium and calcium ions to inhibit the shale hydration swelling, and use sulfonated asphalt and SMP to seal the bedding fracture.
Basic components: KOH (or K2CO3), lime, polymer, SMP-1, sulfonated asphalt, etc.