威德福公司可钻式钻鞋的结构特点及现场应用

Characteristics and Applications of Drillable Drillshoe from Weatherford

套管钻井技术现场施工中处理钻头主要有钢丝绳更换钻头和应用可钻式钻鞋两种方法,前者操作较为复杂,而后者不需要对钻头进行任何回收处理,就可以立即实施固井作业。威德福公司可钻式钻鞋(DrillshoeTM)已经发展到第三代产品。其中第一代、第二代钻鞋主要由钢质本体、铝质可钻式内核及刀翼、热稳定性金刚石或碳化钨切削齿、铜质或陶瓷质喷嘴以及保径垫所组成。第三代钻鞋主要由钢质本体、铝质内核、金刚石切削齿和钢质刀翼、侧翼保径垫以及尾端扶正器所组成,其刀翼是不可钻的,但是,经过简单操作即可将其胀开,从而使钻头转化为可钻。威德福的可钻式钻鞋在大量表层套管钻井及尾管钻井中的应用表明,应用该钻鞋不但可以大大缩短作业周期、节约钻井费用,而且可以解决钻井液漏失、套管下不到位等问题,因此可以广泛用于表层套管钻井以及一些渗漏层的尾管钻井施工中。

There are two methods for bit operations in casing drilling, namely using wire line to change bit and using drillable drillshoe. The first is more sophisticated while the second can implement well cementing immediately without any recovery. So far, Weatherford has developed three generations of DrillshoeTM. DrillshoeTM Ⅰ and Ⅱ mainly consists of a body made from steel, a nose made from aluminium alloy, cutters made from dense tungsten carbide or thermally stable diamond （TSP）, copper or porcelain nozzles, and gauge pads, etc. Generation Ⅲ of Drillshoe^TM mainly consists of.. steel body, aluminum nose, diamond cutters, steel blades, gauge pads, and stabilizer. The blades held on nose are not drillable, but through a very simple displacement operation they can be expanded so that the bit is changed into drillable. Its applications in extensive casing drilling operations show this tool can remarkably reduce drilling time and save drilling cost, as well as solve the problems of fluid loss and make sure the casing reaching TD. Therefore, it can be used widely in surface casing drilling and liner drilling in formations with the problem of fluid loss.