囊袋多节捆绑式绳索取心钻具的设计与应用

Design and application of multi-section bundled bag wire-line coring drilling tools

由于现有的普通绳索取心钻具缺乏隔水与护心装置,在松散、软弱、破碎等复杂地层取心钻进时,破碎岩心易被冲蚀,提钻过程中岩心易脱落,使岩心采取率和取心质量达不到设计要求,甚至无法采取到岩心。针对上述问题,设计了一种囊袋多节捆绑式绳索取心钻具。该钻具在普通绳索取心钻具基础上增加了多节捆绑式囊袋总成结构,并与超前侧喷钻头配合使用。囊袋可以隔绝冲洗液,有利于取得原状岩心,通过分段捆绑,可以有效包裹住岩心,防止其在提钻过程中脱落。超前侧喷钻头改变了冲洗液流向,起到隔水与护心的作用。现场应用表明,该钻具能够完成在松散、软弱、破碎等复杂地层的钻探工作,岩心采取率达90%以上,取心质量也得到明显提高。

Because the existing conventional wire-line coring drilling tool lacks the water-proof and core-protecting device,the broken core is easily eroded when the core is drilled in a complicated layer such as loose,weak,broken layers and the core is easy to fall off during the lifting process,so that the coring rate and core quality are not up to the design requirements,and even core can not be taken to.In response to the above problems,a bag-type wire-line coring drilling tool was designed.The drill adds a multi-section bundled bag assembly structure to the conventional wire-line coring drilling tool is used in conjunction with the front side spray bit.The bag can isolate the rinsing liquid,which is beneficial to obtain the undisturbed core.By segmenting the bundle,the core can be effectively wrapped to prevent it from falling off during the drilling process.The front side spray bit changes the flow direction of the rinsing liquid and acts as a water barrier and a protector of core.The field application shows that the drilling tool can complete the drilling work in complex layers such as loose,weak and broken layers.The coring rate is over 90%,and the core quality is also obviously improved.