用于YC21—1—3井的高温高压钻井液工艺

High temperature and high pressure drilling fluid technology for YC21- 1 -3 well

YC21—1—3井是位于海南省莺琼盆地的崖城21—1构造上的一口高温气压、高难度深井,井深4688m。此井用的PYRODRILL钻井液体系由改性褐煤(基本材料)、高温有机包被剂及高温稳定剂等组成,具有良好的热稳定性及一定的抗盐、抗水泥侵的能力,但抑制性差。在实际钻井中加强钻井液的处理、维护,及时测定钻井液高温性能;严格控制其低密度固相含量和膨润土含量,避免各种形式的污染是保证钻井液性能稳定的重要措施。本井完井测试的钻井液是在地面一次性配制的。当它一次性替入井后,经历高温变化时间快,反应剧烈,高温对其性能的影响在常温状态下是不能预测的。高温和高温作用的时间是评价高温钻井液的重要因素。

YC21 -1 -3 well is located in Yingqiong basin of Hainan, with a depth of 4688 meters, bottom hole temperature of 200℃. The mud densify of this well reached 2. 33 g/cm3. Pyrodrill fluid system adopted is composed of Chemtrol - x (a modified lignite), Miltemp, Kemseal, Pyrotrol and Polydrill. Measures in operation are strictly controlling the concentration of low density solids and bentonite, and monitoring mud properties in time. The dosage of additives, procedures of fluid formulating and maintaining at well site are presented.