| 摘要 |
Oil-based drilling fluids contain a continuous oil phase and discontinuous water phase, together with 3-15 vol.% additive to control the density and gelling agents. Surfactant used comprises a small amt. of water-soluble monoalkyl aryl sulphonate contg. a 8-16C alkyl gp. sufficient to maintain the weighting additive in the oil-wetted state. Compsns. esp. for release of drilling rods from borehole drillings. Since the surfactant is solid, it can be incorporated with other solid ingredients and pre-packed ready for use; requiring addn. of diesel oil, water and weighting additives. It is effective in presence of impurities e.g. water, Cr lignosulphonates and Ca and Mg salts. |
