但后两者都是影响井壁应力分布和岩石力学性能而造成井壁不稳定。
The last two factors induce borehole instability both by affecting stress distribution around wellbore and material properties of rock.
井壁不稳定问题已严重制约着新站地区的钻井作业，并带来了很大的经济损失。
And the drilling operations in Xinzhan area have been influenced by unstable borehole walls, and economic loss is heavy.
着重探讨了煤层并壁不稳定机理，结果表明，煤层井壁不稳定是物理、化学、力学与机械等因素的综合效应。
The result shows that coal seam wellbore unstability is a synthetic effect caused by such factors as physics, chemistry, mechanics and machinery.
经现场应用表明，该体系舱有效地解决堂古5井四开井段盐膏层易溶解、易垮塌造成的井壁不稳定问题，满足了堂古5井的钻井施工要求。
The application in the wellsite shows that the new drilling fluid system effectively solves the problems of bore-hole stability and satisfies for the drilling operation of Tanggu 5 well.
地层不稳定，井壁垮塌严重。
研究表明，影响空气钻井井壁稳定的主要因素有三个：力学不稳定，水化不稳定和岩体破裂或弱面不稳定。
Preexisting research shows that there are three main factors that affect the borehole stability of Air-Drilling: mechanical reason, hydration reason and the Weaked surface instability reason.
研究表明，影响空气钻井井壁稳定的主要因素有三个：力学不稳定，水化不稳定和岩体破裂或弱面不稳定。
Preexisting research shows that there are three main factors that affect the borehole stability of Air-Drilling: mechanical reason, hydration reason and the Weaked surface instability reason.
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