破碎性地层钻井液防塌剂评价方法及应用

EVALUATION AND APPLICATION OF ANTISLOUGHING AGENTS FOR DRILLING FLUIDS USED IN FRAGILE NON DISPERSIVE FORMATIONS

本文分析了破碎性地层井壁不稳定的原因，借助ＯＦＩ１７０５０ 高温高压动失水仪分析了钻井液对地层裂缝、微裂缝的封堵能力，初步建立了破碎性地层防塌的方法及措施，在塔参１ 井应用取得成功。

An evaluating method is suggested for the performance properties of asphaltic antislouphing agents while drilling in fragil non dispersive formations of Tarim basin. The plugging capacity of these agents is determined through filtrate loss time relationships obtained on HTHP dynamic water loss apparatus OFI 170 50 with artificial core samples of similar fracture wideness as in the aimed formations. It is shown that commercial antisloughing agents OXA(oxidized asphalt), XA(asphalt) and HL 3(emulsified asphalt) are effective at 125-140℃ as the particles of these materials soften at the same temperatures; FT 1(sulfonated asphalt) is not effective owing to much lower softening point of the material particles. On the basis of the above investigation, OXA and then HL 3 are introduced into the well mud in drilling in cavey formation strata(depth>6000 m) of well TAC 1, Tarim, and result in notable stabilization of the borehole meanwhile FT 1 and another sulfonated asphalt material SAS are not effective.