coring bit

Higher core recoveryassisted in coring operations when this kind of bit is used for hole enlargement.

加深井钻进,用双心钻头可增大环空间隙,提高固井质量.

This new coring bit is especially suitable for coring in medium to medium-hard plastic-brittle formation, and the maximum footage of a single bit reaches 115. 71m with a penetration rate of 1. 45m/ h.

这种新型取心钻头特别适用于中到中硬塑脆性地层的取心钻进，单只钻头最高进尺达115.71m（机械钻速1.45m／h），创国内同类取心钻头单只进尺的最高纪录。

Problems and countermeasures of wireline coring drilling in "walk" formation in a uranium mine in Guangxi are introduced with type selection test for diamond drilling bit.

通过绳索取心钻进金刚石钻头选型试验，介绍了广西资源县向阳坪铀矿区打滑地层中绳索取心钻进存在的问题及采取的技术措施。

It discusses the influences of each factor on coring of mixing pile from borer, drilling level, boring bit, geologic condition, length, arrangement and type of pile, stadium and external condition, in order to ensure coring quality of mixing pile.

从钻机、钻探水平、钻头、地质条件、桩长、桩布置及桩类型、龄期、外界条件等方面详细论述了各影响因素对搅拌桩取芯的影响，以保证搅拌桩的取芯质量。

So every so often a sample is obtained with a coring bit.

因此时常要用芯钻头取样。