乌兰哈达变质岩地层地热勘探井钻头选择与取心工艺

Bit Selection for Geothermal Exploration Well in Metamorphic Strata of Wulanhada and the Coring Technology

内蒙古自治区察右后旗乌兰哈达苏木地热勘探井井深2006.87 m。采用石油30型钻机施工,钻遇地层大部分为变质岩,达1500 m以上,对牙轮钻头损坏严重,同时施工要求进行18次岩心采取。经过对钻头的试用、选择,最后选用HJ637G型牙轮钻头,钻进时效可达0.8～1.2 m,使用寿命可达到80～100 h。取心段采用川7-4型双管单动取心筒配合金刚石钻头,岩心采取率可达70%～95%。

Being 2006. 87m in depth, Wulanhada geothermal well was constructed with 30 type oil drilling rig in the Inner Mongolia Autonomous Region Chayouhou Banner, most drilled formations, more than 1500m, were metamorphic rocks, the roller bits were seriously damaged; and 18 times of coring were required for the construction. HJ637G roller bit was selected, the drilling efficiency per hour was up to 0. 8 - 1.2m and the service life reached 80 ～ 100h. Chuan 7 -4 double tube single rotary coring barrel was used, the core recovery could be 70% ～ 95%.