基于岩石可钻性分级的月壤可钻性初探

在分析"Apollo"和"Luna"月表实钻进取心对象的基础上,依据相关的概率分析结果,得出在月表钻进遇见岩石的几率≤5%,月表钻进对象是月壤的可能性为95%;分析了月壤的物理力学特性,确定月壤的内摩擦角和内聚力是影响月壤可钻性的主要特性参数,基于岩石可钻性模型建立了以内摩擦角和内聚力为主要参数的月壤可钻性的初步模型;对"Luna"与"Apollo"的月表钻探取心在钻进方法、钻头材料、钻进深度和钻进速度等方面进行了分析比较,参考岩石可钻性分级指标,得到了月壤可钻性的初步评价结果。     

关于岩石可钻性分级

五十年代初,我国在制订全国岩心钻探统一生产定额时,曾制订了一个按可钻性划分岩石的十二级分级表,1958年修订过一次,迄今未改.时隔二十多年,钻探技术已向前大大发展,由硬质合金、铁砂和钢粒钻进,发展到金刚石小口径钻进,这个分级表,显然已不适用.不管钻探技术如何发展,按可钻性划分岩石级别的方法是可取的.但只有依据野外实际钻进条件,在岩石中进行实际钻进所得可钻性的结果,确定岩石级别才是比较客观的.因为在实验室中无法造成与岩石自然赋存完全相同的条件,并且在实验室中所模拟的钻进条件也不同于现场.故笔者认为,实     

金刚石钻进岩石可钻性分级新方法

一种特殊设计的装置(包括一个装在小杆上的孕镶金刚石钻头),可在衡压下对岩石进行刻槽,用以确定岩石的可钻性并进行分级。由于刻槽深度,即岩心直径尺寸的变化量是岩石硬度的函数;金刚石的磨损量是岩石研磨性的函数,故该法可用作金刚石钻进的岩石分级。     

SDY-1型微钻试验机

微钻机是一种用小尺寸钻头进行模拟钻进的钻机，是进行岩石破碎和可钻性研究的必要手段。1984年地矿部频布的《金刚石岩心钻探岩石可钻性分级表》（试行）中将微钻指标列为岩石可钻性分级的指标之一，因此微钻机就成为岩石可钻性分级的主要设备之一。由于微钻要求稳定的钻压和转速，且要求将较短时间内的钻进参数和钻进指标准确无误地记录下来，因此微钻机必须能稳定加压并正确测试各钻进参数和钻进指标。我们在完成岩石可钻性分级研究课题的过程中，研制了较为适用的SDY-1型微钻机，用其钻进了400余块岩样。现将该微钻机简要介绍如下。     

对回转破碎比功岩石可钻性分级的初步研究

用破碎单位体积岩石所需能量——比功来衡量岩石抵抗钻进的能力,一直是一些岩石可钻性研究者所追求的。由于用单位体积破碎功确定岩石可钻性存在“输入功率用于其它方面和用于切削岩层或总体积破碎功的比值对每种岩石来说都是不同的,并很难测量”,而且钻进过程中输入能量的70~90%都转变为热能被冲洗液带走,而不同钻进方法、不同钻头形式、不同钻进参数下变为热能所消耗的能量是不同的。这些问题至今均未能得到解决,因此用比功进行回转钻进的可钻性分级未能实现。为了寻找更全面地反映岩石抵抗破碎能力的参量,使岩石可钻性分级更准确,我们     

岩石可钻性多因素分级

研究岩石可钻性是为了制定生产定额，衡量钻探工作的技术经济效果以及为钻探设备、钻头、钻具的设计提供设计基础数据。1958年我国颁布了适合于硬质合金钻进和钻粒钻进的岩石可钻性十二级分级表。随着金刚石钻探的全面推广，这一分级表越来越不能适应需要。1984年地矿部探矿工程装备工业公司颁布了《金刚石岩心钻探岩石可钻性分级表》（试行），标     

岩石力学性质及可钻性分级研究

岩石力学性质和可钻性是分析和评价岩石抵抗破碎和钻进的基本性质，也是合理选择碎岩工具和工艺的基础。因此，对岩石力学性质和可钻性的深入研究，采用能够反映某种碎岩方式实质的综合力学性质指标评定岩石可钻性，应用数理统计学原理，依据岩石力学性质和可钻性指标，建立表示岩石可钻性的数学模型，并以此模型进行岩石可钻性分级，可及满足岩土工程施工生产的急需。     

切槽法金刚石钻进岩石可钻性分级

本文提出了岩石可钻性分级的主要观点，提出了测定金刚石钻进岩石可钻性的新方法——切槽法。切槽法的破岩实质与孕镶金刚石钻头钻进相似。该法在一次测定中同时取得△d和△W两项指标，可综合反映钻进岩石的难易程度和岩石的研磨性。在此基础上，提出了按△d、△W综合分级的8级4类分级方案，并对岩性特征、钻头使用范围作了分析。在实验室和现场测定中证明所测岩石可钻性与钻孔效果之间有良好的相关性。独创性地研究了“JZ-1型岩石可钻性测定仪”，它既可用于实验室，又可用于现场。经室内外试验初步证明，该仪器简单、性能稳定、使用方便、     

用模拟法进行岩石可钻性试验

岩石可钻性分级工作是岩心钻探生产计划与定额管理工作的重要基础,也是合理选用钻进方法与钻进工艺的主要依据。是生产中比学赶帮的必不可少的指标。长期以来,人们曾不断研究着岩石可钻性的分级方法,到目前止,已有的方法可以概括为以下五大类:     

煤系钻探岩石可钻性分级方法的研究

研究了煤系中采用硬质合金钻进工艺时岩石可钻性分级的指标体系及测试方法;研制了一套能在野外流动条件下进行岩石可钻性分级测试的轻便仪器及工具。在7项分级指标体系中,压入强度、研磨性、塑性系数和用微型针状硬质合金钻头测试“微钻钻速”是首次应用,尤以用小试样测试“压入强度”及用微型针状硬质合金钻头测试“微钻钻进速度”两项指标能有效地反映煤系软岩石分级档次,可以弥补用微型孕镶金刚石钻头在6级以下较软岩石中无法钻进或达不到钻进指标的不足。     

Development of a New Index to Assess the Rock Mass Drillability

Knowledge of drillability of rock masses in engineering projects is very important in determining drilling costs. In drilling operations, so many parameters such as the properties of rock and the drilling equipment affect the drilling performance. In this study, after discussing the rock mass drillability process and identifying all the effective parameters, interaction matrixes based on the rock engineering systems, that analyze the interrelationship between the parameters affecting rock engineering activities, is introduced to study the rock mass drillability tribosystem. Given that interaction matrix codes are not unique numbers, and then possible interactive intensities are calculated for each matrix and a group decision-making method, Fuzzy–Delphi–AHP technique has been used to obtain appropriate weights. As a result, rock mass drillability index (RMDI) is presented to classify the rock mass drillability. The results indicate the ability of this method to analyze rock mass drillability procedure. Drilling data along with laboratory rock properties from Sungun copper mine were collected and were ranked according to the new classification system. Fifteen zones at the mine site were ranked based upon the new index RMDI and a reasonable correlation was obtained between measured drilling rate at the zones and RMDI data.     

基于机械比能理论的煤岩可钻性分级方法

通过机械比能对煤矿瓦斯抽采钻孔过程中的围岩进行可钻性分级,可为钻机调整钻进参数提供依据。针对瓦斯抽采钻孔过程中人工判层难度大、效率低的问题,提出一种以机械比能为可钻性评价指标,结合极限学习机的煤岩可钻性分级方法。采用ABAQUS建立了PDC钻头破岩仿真模型,从材料类型、钻头转速和钻压力三个方面研究了PDC钻头破岩过程中钻进速度和机械比能的变化规律。同时,获得了钻进参数及机械比能的训练数据,采用极限学习机分别对钻进参数和机械比能数据进行学习,最后,对这两种可钻性分级指标下的分级准确率进行对比。结果表明:以机械比能作为可钻性指标时的分级准确率达到90%以上,高于以钻进参数作为可钻性指标时的准确率。分级结果可以为钻机调整钻进参数、实现自适应钻进提供理论依据。      

准噶尔盆地中部地区钻头优选技术应用研究

岩石可钻性是决定钻井效率的基本因素,反映了钻进时岩石破碎的难易程度,是合理选择钻进方式、钻头类型和设计钻进参数的依据。基于地层岩石可钻性的计算方法,结合实钻井的测井资料分析,建立了准噶尔盆地中部区块地层岩石可钻性剖面,并以此为依据推荐了适用于不同地层的钻头类型,现场应用结果表明,所用钻头具有很好的适用性,能够进一步提高准噶尔盆地中部地区的机械钻速,对于该地区的后续钻井钻头类型的选择具有重要的指导意义。     

金刚石钻进微钻法岩石可钻性分级的探讨

岩石可钻性的分级是确定生产定额、设计钻头和选择最佳参数的依据。本文论述了作者在实验台上用微钻法进行岩石分级的研究成果。该实验台是自行设计并可以同时自动记录9个钻进参数的一种装置,微钻法可以很好地表示在两向力同时作用下,岩石破碎过程的主要力学特征。岩石抗破碎阻力是岩石机械性质的综合反映,因此,以往用单一的性质来进行分级并不完善,用微钻法进行分级、经野外实践,符合率可达85％以上。     

Drillability prediction: geological influences in hard rock drill and blast tunnelling

 Usually the main subject in preliminary site investigations prior to tunnelling projects is the prediction of tunnel stability. During the past years in conventional drill and blast tunnelling, problems have occurred also connected to the accurate prediction of drillability in hard rock. The drillability is not only decisive for the wear of tools and equipment but is – along with the drilling velocity – a standard factor for the progress of excavation works. The estimation of drillability in predicted rock conditions might bear an extensive risk of costs. Therefore, an improved prediction of drilling velocity and bit wear would be desireable. The drillability of a rock mass is determined by various geological and mechanical parameters. In this report some major correlations of specific rock properties and especially geological factors with measured bit wear and drilling velocity are shown. Drilling velocity is dependent on a lot of geological parameters: Those principal parameters include jointing of rock mass, orientation of schistosity (rock anisotropy), degree of interlocking of microstructures, porosity and quality of cementation of clastic rock, degree of hydrothermal decomposition and weathering of a rock mass. Drilling bit wear increases with the equivalent quartz content. The equivalent quartz content builds the main property for the content of wear-relevant minerals. For various groups of rock types different connections with the equivalent quartz content could be detected. In sandstone bit wear is also dependent on porosity or the quality of the cementation. Finally, an investigation program is submitted, which helps to improve the estimation of rock drillability in planning future tunnel projects. Received: 14 June 1996/Accepted: 10 January 1997     

Quantitative assessment of rock texture and correlation with drillability and strength properties

Summary A dimensionless quantitative measure of rock texture, describing grain: —shape, orientation, degree of grain interlocking and relative proportions of grains and matrix (packing density) has been developed. Data required for the model are obtained by image analysis of thin sections and concerns percentage areas of grains and matrix, length, breadth, perimeter, orientation and area of each grain in the viewing window. The results of rock strength, diamond and percussion drillability tests in eleven sandstones, marbles and igneous rocks are reported, and correlated with the developed texture coefficient. The texture coefficient returns highly statistically significant correlations with rock strength and drillability data. Sandstones have low texture coefficients and high drillability whereas igneous rocks have high texture coefficients and low drillability. With particular reference to percussive drillability it is suggested that extensional crack propagation in the sandstones in an energy efficient process since fracture paths propagate through the weak phyllosilicate matrix. Extensional crack propagation in the igneous rocks is an energy intensive process since a significant proportion of the available drilling energy is consumed in the formation of intra-granular fracture paths. Observational and correlated data are supportive of the suggestion that the texture coefficient is a measure of the resistance of the microstructure of a rock to crack propagation, whether it be inter-or intra-granular. The texture coefficient can be used as a predictive tool for the assessment of drillability and rock strength properties. The technique offers a useful approach in understanding fracture initiation and growth as controlled by the texture of intact rock samples.     

南海西部海域难钻地层特征及破碎机制研究

近年来,南海西部海域部分油田的下第三系地层机械钻速较慢,严重影响了勘探开发进度,为了降低钻井成本,增加钻井时效,必须掌握该海域难钻地层的特征及破碎机制。首先开展了岩屑矿物组分测定,结合录井资料,掌握了南海西部海域难钻地层的岩性特征。在对难钻地层的破坏强度、硬度、塑性系数、可钻性、研磨性等相关参数室内试验的基础上,建立了该地层岩石力学参数的预测模型,并基于30口测井的资料建立了难钻地层抗钻特性剖面和南海西部海域三维可钻性剖面,揭示了区域难钻地层的分布情况及抗钻特性;为解决难钻地层的工艺技术难题,还进行了难钻地层PDC钻头的破岩机制试验研究,研究了PDC钻头牙齿齿形、钻压和转速对破岩效率的影响。研究发现：北部湾盆地建议提高钻头的攻击性,并采用高转速的动力钻具复合钻进方式;珠江口盆地应提高钻头复合片的耐磨性,采用较高钻压和合理顶驱转速,为更好地控制钻井成本和提高钻井综合经济效益提供技术指导。     

高能射流式液动锤在花岗岩中的钻进研究

由于干热岩地层通常为火成岩,研磨性强、可钻性差,现有常规工艺方法钻进效率低,为此专门研制了用于干热岩钻进用的SC-86H型高能射流式液动锤,并对该高能射流式液动锤样机进行了地面钻进试验。试验采用可钻性等级为10级的完整花岗岩作为钻进对象,观测了冲锤质量、活塞行程和泵量对机械钻速的影响。试验结果表明：增大冲锤质量、活塞行程和泵量有利于提高机械钻速。试验过程中获得的最大机械钻速为5.19 m/h,较常规回转钻进机械钻速提升显著。     

元坝区块提高钻井速度技术方案探析

在总结分析前期钻井经验的基础上,从地质因素、钻井复杂情况、岩石可钻性、地层温度、钻井液密度、井身结构等方面分析了目前影响元坝区块深井钻井速度提高的因素。指出井身结构层次有限,不能完全有效封隔不同压力体系的地层以及须家河组地层可钻性差、埋深较深、段长,不能利用空气钻进行钻进是影响机械钻速的2个最重要原因。提出了气体钻井方案、钻头选型方案、进口动力钻具配合高效钻头钻须家河地层方案,以及采用特种井眼尺寸井身结构方案,为元坝区块深井钻井提供技术支持。