霍003井钻井完井液技术

Drilling and completion fluid technology for Huo-003 well

霍003井位于准葛尔盆地南缘霍尔果斯背斜10井区,井下具有粘弹塑性、易造浆的软泥岩和破碎微裂缝发育的硬脆泥岩交替出现,极易造成缩径阻卡和井壁垮塌。安全钻井液密度窗口几乎不存在,使钻井液密度选择和使用极为困难。霍003井一开使用聚合物正电胶钻井液,二开使用钾基聚磺钻井液,三开和四开使用氯化钾有机酸钾多功能封堵磺化钻井液,采用强抑制性和多功能多元封堵的措施,经过现场合理调配维护,形成了一套较好的钻井液体系。现场应用表明,该套钻井液体系抑制性和封堵能力强,使用合适的密度、粘度和切力,对抑制软泥岩分散造浆、膨胀、缩径和裂缝发育硬脆泥岩的垮塌起了重要作用;井下复杂事故出现次数减少,钻井速度较快,钻井周期较短,钻井总成本较低,整体经济效益较好。

Huo-003 well was in 10th well field of Zhun Ge'er basin located in the south edge of Huo Er Guo Si anticline. The papa with viscoelasticity and high yield and the hard brittle papa with mature microfracture were interbedded which resulted in tight hole and sticking and wellbore caving. It was very difficult to determine the density of drilling fluid due to almost none of the safe density window. Initial open in well of Huo-003 used polymer based mixed metal layered hydroxide compound fluid, while potassium based polysulfonate drilling fluid for second opening and potassium chloride coupled with organic acid potassium multifunction sulfonate sealing drilling fluid for third and fourth opening. Thus a preferable drilling fluid was developed by enhancing inhibitive significantly and multiple function and multiple sealing, and appreciate adjusting and maintenance in site. It was shown from the in-situ data, this fluid used for third and fourth opening had powerful inhibitive and sealing effect, and it could stop papa from dispersion and making mud, swelling and tight hole and prevent the hard brittle papa with mature microfracture from sloughing. And also, it could reduce bottom hole complicate accidents and a quick drilling speed and a short drilling period could be gotten and thus could decrease total cost and enhance overall economic benefit