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石油钻杆接头超声波检测方法研究【研究类】【无图】

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石油 钻杆 接头 超声波 检测 方法 法子 研究 钻研
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石油钻杆接头超声波检测方法研究

30页 15000字数+说明书+开题报告+任务书+文献综述+答辩稿+外文翻译

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外文翻译--无损检测.doc

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石油钻杆接头超声波检测方法研究开题报告.doc

石油钻杆接头超声波检测方法研究答辩稿.ppt

石油钻杆接头超声波检测方法研究论文.doc

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目  录

摘  要1

1 绪论1

1.1 超声波检测的概要1

1.2 国内外研究现状1

1.3 本论文的主要工作2

2 超声波检测的基本原理2

2.1 超声波传感器2

2.2超声波探伤基本方法3

2.3 超声波检测的常用方法5

3 系统组成7

3.1超声波检测技术7

3.2检测系统的组成8

3.3 数据显示方法9

3.4探伤数据的显示10

3.5 探伤图像处理及滤波算法11

4 系统的硬件设计13

4.1 单片机系统及显示电路14

4.1.1 芯片74LS24414

4.1.2 四位共阳极LED数码管14

4.1.3 单片机系统及显示电路15

4.2 超声波发射电路15

4.2.1 超声波换能器16

4.2.2 芯片74LS0417

4.3 超声波检测接收电路17

4.3.1 超声波检测接收电路17

4.3.2 芯片CX20106A18

5 系统的设计19

5.1 主函数21

5.2 超声波发生子函数和超声波接收中断函数22

6软硬件调试及性能23

6.1元器件的焊接23

6.2 电路调试与分析23

7结语24

参考文献25

致  谢26



摘  要

   石油钻杆接头是石油开采中重要的专用部件之一。为保证在井下的安全使用,接头不允许有超过标准的缺陷存在。因此,对石油钻杆接头进行缺陷检测已成为其生产中不可缺少的环节。超声检测是应用于钻杆接头缺陷检测的主要方法之一。

   由于钻杆接头的形状复杂、规格较多,同时从使用安全性考虑,又必须对横向和纵向缺陷进行100%探伤,因此,对钻杆接头进行超声波检测具有一定的难度。在实际生产中,大都采用手工探伤方式进行检测;而手工探伤存在生产效率低、探伤质量难等问题。所以,本课题设计了适用于实际生产的钻杆接头超声自动检测系统,它对保证钻杆接头的安全使用具有重要意义。

   本论文主要分四部分讨论了对石油钻杆接头超声波检测方法的研究。

   第一部分首先阐述了超声波管材探伤的一般方法,然后结合石油钻杆接头的特殊性,逐步提出解决其探伤问题的特殊方法。

   第二部分首先介绍了超声波检测系统的组成和探伤数据的显示方式,并对数字图像处理的常用方法进行了简要的介绍;然后对实际探伤数据,根据本系统探伤的特点,提出了有效的图像处理和缺陷提取方法。

   第三部分简要介绍了本探伤系统的应用,对系统实现自动探伤的整体流程作了概括性说明。

   第四部分对装置的整体效果作了客观的评价,并对其未来的应用领域和改进措施进行了讨论。

   论文从实际的工程项目出发,逐一解决了接头检测存在的难点,最终实现了钻杆接头的自动、高效检测。给出了系统的改进方案。

关键词:石油钻杆接头;探头组;探头架 ;图像处理;A扫描;B扫描


内容简介:
中国地质大学长城学院毕业设计(论文)任务书学生姓名李博学号05208330班 级机制0803班指导教师赵晓顺职称讲师单 位河北农业大学毕业设计(论文)题目石油钻杆接头超声波检测方法研究毕业设计(论文)主要内容和要求: 1、 超声波检测机理研究2、 超声波检测新型发展及趋势研究3、 如何将超声波检测应用到石油钻杆接头检测中,以石油钻杆接头具体故障为例展开论述4、 论文一篇毕业设计(论文)主要参考资料:1 在役锅炉压力容器接管角焊缝超声波检测技术与装备J. 机电产品开发与创新, 1997,(03) 2 张志春. 薄壁管对接焊缝超声波检测与评定J. 石油工程建设, 1984, (05) 3 于文勇, 王立海, 杨慧敏, 张希栋. 超声波木材缺陷检测若干问题的探讨J. 森林工程, 2006,(06) 4 何汇. 常规超声波检测技术初步(续)J. 无损探伤, 2002,(02) 5 薛正林, 韩烨, 贾涛, 黄烈勇, 刘觉非. 焊缝超声波检测存在的问题及其技术改进措施J. 油气储运, 2005,(09) 6 黄磊, 李云龙. 管道环焊缝相控阵自动超声波检测技术J. 焊管, 2006,(04)7 黄东流,韦介波,蓝飞. 汽车变速箱焊接齿轮的超声波探伤J无损检测, 2002,(04) .8 郭平英. 一种新的金属功能零件分层快速制造技术研究J中北大学学报, 2006,(03) . 9 张恩君,王海波,范鸿宇,刘秀杰. 汽轮发电机转子齿根超声波探伤研究J哈尔滨理工大学学报, 2003,(04) .毕业设计(论文)应完成的主要工作: 阅读中英文文献资料,研究超声波用于检测的原理,并完成对石油钻杆接头具体故障的检测实例研究,最后进行论文撰写。毕业设计(论文)进度安排:序号毕业设计(论文)各阶段内容时间安排备注1资料的查阅、收集、整理,并撰写文献综述、开题报告、外文资料翻译12月5日1月20日确定基本设计方案2超声波检测机理研究1月21日3月1日3石油钻杆接头实例故障超声波检测3月2日3月15日4撰写论文,整理相关表格资料3月16日4月20日5准备答辩课题信息:课题性质: 设计 论文 课题来源: 教学 科研 生产 其它发出任务书日期: 2011.12.6 指导教师签名: 2011年 12月 6日教研室意见:教研室主任签名:年 月 日 学生签名:中国地质大学长城学院本科毕业论文外文资料翻译系 别: 工程技术系 专 业:机械设计制造及其自动化姓 名: 学 号: 2012 年 3 月 1 日外文资料翻译译文无损检测是在不损坏工件或原材料工作状态的前提下,对被检验不见的表面和内部质量进行检查的一种检测手段,Nondestructive Testing(缩写NDT)。机械振动在介质中的传播过程叫做波,人耳能够感受到频率高于16赫兹,低于20000赫兹的弹性波,所以在这个频率范围内的弹性波又叫声波。频率小于10赫兹的弹性波又叫次声波,频率高于20000赫兹的弹性波叫做超声波。次声波和超声波人耳都不能感受。超声波的特点:1、超声波声束能集中在特定的方向上,在介质中沿直线传播,具有良好的指向性。2、超声波在介质中传播过程中,会发生衰减和散射。3、超声波在异种介质的界面上将产生反射、折射和波型转换。利用这些特性,可以获得从缺陷界面反射回来的反射波,从而达到探测缺陷的目的。4、超声波的能量比声波大得多。5、超声波在固体中的传输损失很小,探测深度大,由于超声波在异质界面上会发生反射、折射等现象,尤其是不能通过气体固体界面。如果金属中有气孔、裂纹、分层等缺陷(缺陷中有气体)或夹杂,超声波传播到金属与缺陷的界面处时,就会全部或部分反射。反射回来的超声波被探头接收,通过仪器内部的电路处理,在仪器的荧光屏上就会显示出不同高度和有一定间距的波形。可以根据波形的变化特征判断缺陷在工件重的深度、位置和形状。 超声波探伤优点是检测厚度大、灵敏度高、速度快、成本低、对人体无害,能对缺陷进行定位和定量。超声波探伤对缺陷的显示不直观,探伤技术难度大,容易受到主客观因素影响,以及探伤结果不便于保存,超声波检测对工作表面要求平滑,要求富有经验的检验人员才能辨别缺陷种类、适合于厚度较大的零件检验,使超声波探伤也具有其局限性。 超声波探伤仪的种类繁多,但脉冲反射式超声波探伤仪应用最广。一般在均匀材料中,缺陷的存在将造成材料不连续,这种不连续往往有造成声阻抗的不一致,由反射定理我们知道,超声波在两种不同声阻抗的介质的界面上会发生反射。反射回来的能量的大小与交界面两边介质声阻抗的差异和交界面的取向、大小有关。脉冲反射式超声波探伤仪就是根据这个原理设计的。 脉冲反射式超声波探伤仪大部分都是A扫描式的,所谓A扫描显示方式即显示器的横坐标是超声波在被检测材料中的传播时间或者传播距离,纵坐标是超声波反射波的幅值。譬如,在一个工件中存在一个缺陷,由于缺陷的存在,造成了缺陷和材料之间形成了一个不同介质之间的交界面,交界面之间的声阻抗不同,当发射的超声波遇到这个界面之后就会发生反射,反射回来的能量又被探头接收到,在显示器屏幕中横坐标的一定的位置就会显示出来一个反射波的波形,横坐标的这个位置就是缺陷波在被检测材料中的深度。这个反射波的高度和形状因不同的缺陷而不同,反映了缺陷的性质。钻杆接头和转换接头(以下简称接头)是石油钻柱的重要构件 近年来,随着我国石油工 业的飞速发展,接头用量逐年增加。但是,由于国产接头质量不高,导致接头断裂事故频繁发生。根据石油管材研究中心对华北、胜利、大庆、中原、大港、吉林、新疆等油田的现场调查, 19841986年国产接头的断裂事故达100多起。接头的大量失效,造成了严重的经济损 失例如,中原油田一中美合作钻井队于1986年4月发生一起国产转换接头断裂事故,直接 经济损失达40多万美元据估计,全国每年因接头断裂而造成的经济损失在l00o万元以 上。由此可见,提高接头质量,对于减少接头早期失效事故,提高钻井效率和石油工业的经济效益,具有十分重要的意义。接头的服役条件比较恶劣,在使用过程中要承受拉伸、扭转、弯曲、振动、冲击等多种复杂载荷的作用。根据接头的服役条件,要求接头具有较高的强度和良好的塑韧性,为了达到这一要求,国外在接头选材及热处理方面采取了一系列措施,用钢主要采用4100系列(CrMo系),主要牌号有4l37H、-4l40H等。我国合金钢系列基本上是从苏联FOCT 标准中移植过来的,与美国合金结构钢系列差别很大 在GB307782中虽然也有CrMo钢录列,但含碳量和主要合金元素配比与4100系列相差颇丸往往难以替代。以国 勺用来生产接头的主要钢种35CrMo为例,碳、锰含量与4l37H、4140H相差较大,即使采用含碳量较高的42CrMo钢,由于锰含量较低,淬透性也达不到4140H的水平。在热处理工艺方面,国外接头生产厂普遍采用可控气氛炉加热,在接头内外表面加工完后进行光亮淬火。国内接头热处理多采用普通空气炉加热,淬火时接头内外表面均留有较大的加工余量,对热处理效果有很大的影响从对国内外接头热处理条件的对比分析可知,国内对接头用钢的淬透性应比国外有更高的要求目前,国内接头用钢十分混乱除一些专业生产厂采用35CrMo外,一些地方小厂甚至采用45Mn、30CrMnTi等淬透性很差的钢种,有些甚至不经热处理。近年来,找们从全国各袖珥收集了近百件接头断裂失效样品,对这些失效接头的分析结果 表明,绝大多效属于低应力脆断造成接头低应力脆断的根本原因是韧性太差绝大 多数断裂接头的韧性指标C 在30J以下,有的还不足10 J失敷分析还表明,低韧性往往与 不良的显馓组织相对应 这些接头的显微组织为回火索氏体+上贝氏体+铁索体或铁索 体+珠光体,晶粒粗大这说明,接头韧性差的最终原因是选材及热处理不当造成的。国外接头(主要是钻杆接头)主要选择日本、美国等用4137H或4140H生产的接头及德 国用36CrNiMo4生产的接头26只4100系列接头的解剖分析结果(见图3)表明,接头的 强度指标较高,平均夏比V形缺口冲击功Cv为 785J,绝太多效接头的韧性指标C 在54J以 上。7只36CrNiMo4接头的解剖分析结果表明,在强度指_标与4137H或4140H接头接近或略高的情况下,韧性指标较高,达916 J,全部试样的c 值在54J以上,断口形貌转化湿 度均较低(Fo54J的仅占3;强度与韧性指标二者之一不符合要求的各占255;强度与韧性指标均不符合要求的占46;断口形貌转化温度较高(FATTo24-)对比分析表明,德国采用的36CrNiMo4钢是生产接头的较好钢种国内采用35CrMo等钢,在现行热处理条件下难以满足接头的性能要求。从对国外接头的解剖分析结果来看,德国36crNiMo4接头性能较好,这与它的高淬透性密切相关前已述及,由于国内接头生产条件的限制,对接头用钢的淬透性应有更高的要求。因此,钢种的淬透性应作为选材的主要依据同时,应考虑热处理工艺性能和经济性。就淬透性而言,40CrNiMo、40CrMnMo与德国36CrNiMo4比较接近从性能角度考虑,上述几种材料经过正确的热处理,常规性能基本一致。所不同的是含镍钢的低温韧性较好。从热处理工艺性能来看,36CrNiMo4和4OcrNiMo这两种钢比较成熟,热处理工艺性能比较稳定从上述试验结果来看,加CrMnMo钢的热处理工艺性良好,完全可以满足接头的性能要求而且40CrMnMo符合我国资源情况,价格便宜。因此,40CrMnMo完全可以用来代替36CrNiMo4和40CfNiMo生产接头根据上述对比分析,36CrNiMo4是生产接头的良好钢种在国内36crNiM04供应不足的情况下,可用符合我国资源情况的40CrMnMo代替36CrNiMo4生产接头为了降低生产成本,对一些小规格的转按接头( 127mm),也可采用35CrMo或42CrMo钢生产。我们将上述研究结果先后介绍给宝鸡石油机械厂、高峰机械厂等单位,得到了普遍采用。按照我们推荐的材料及热处理工艺生产的各种接头可完全达到SY5290 91、 SY520087及API Spec7的规定,性能达到了国外同类产品的先进水平。宝鸡石油机械厂按推荐的材料及热处理工艺已生产36CrNiMo4和40CrNiMo接头1万余只,生产 40CrMnMo接头5000余其,在油田使用后,束发生一起断裂事故。目前,这项研究结果已被越来越多的生产厂采用。前几年,国内各油田每年发生接头脆性断裂事故近100起。在有关部门的支持下,经管材研究中心的试验研究,国产接头的质量有了较大幅度的提高,井促进了各油田接头使用和管理水平的提高,接头脆性断裂事故从取来的每年100起减少至目前的每年大约1O起。按每起断裂事故的直接经济损失10万元计算,则每年可减少直接经济损失900万元。按全国每年约需3万只接头计,若以40CrMnMo代替40CrNiMo生产接头,每只接头可节约成本180元,则每年可节约540万元。另外,由于接头的质量水平提高,使用寿命延长,必将产生巨大的社会效益。 目前各油田仍在使用部分质量低劣的接头,这是导致接头断裂的根本原因。如今后全部使用兼备高强度和高韧性的36CrNiMo4、40CrNiMo或40CrMnMo接头,必将大大地提高井效率,降低钻井成本,提高整个石油工业的经济效益。外文原文Nondestructive testing without damage to the workpiece or raw material working condition under the premise, to be tested not see surface and internal quality inspection as a means of detection, Nondestructive Testing ( abbreviated NDT ). Mechanical vibration propagation in the medium is called the wave, the human ear can feel the frequencies higher than 16 Hz, below 20000 Hz by elastic wave, so in this frequency range of the elastic wave and acoustic wave. Frequency of less than 10 Hz elastic wave is also called acoustic frequencies higher than 20000 hz, the elastic wave is called ultrasonic. Sonic and ultrasonic ear cant feel.Ultrasonic flaw detection has the advantages of high sensitivity, detection of large thickness, high speed, low cost, harmless to the human body, can defect positioning and quantitative. Ultrasonic flaw detection on defects of the display is not intuitive, testing technical difficulty big, susceptible to subjective and objective factors, as well as the results of the testing is not easy to preserve, ultrasonic detection on the work surface should be smooth, require experienced inspectors to identify the defect types, suitable for larger thickness of parts inspection, so that the ultrasonic flaw also has its limitations. Ultrasonic flaw detector for variety, but the pulse reflection type ultrasonic flaw detector is the most widely used. Generally in homogeneous materials, the presence of defects will cause the material discontinuity, the discontinuity caused by acoustic impedance is often inconsistent, reflected by the theorem we know, in two different acoustic impedance of the dielectric interface will be reflected. the reflected energy and the size of the interface of the media on both sides of the acoustic impedance of the differences and interfacial orientation, size. Pulse reflection type ultrasonic flaw detector is based on the principles of design.Ultrasonic flaw detection has the advantages of high sensitivity, detection of large thickness, high speed, low cost, harmless to the human body, can defect positioning and quantitative. Ultrasonic flaw detection on defects of the display is not intuitive, testing technical difficulty big, susceptible to subjective and objective factors, as well as the results of the testing is not easy to preserve, ultrasonic detection on the work surface should be smooth, require experienced inspectors to identify the defect types, suitable for larger thickness of parts inspection, so that the ultrasonic flaw also has its limitations.Ultrasonic flaw detector for variety, but the pulse reflection type ultrasonic flaw detector is the most widely used. Generally in homogeneous materials, the presence of defects will cause the material discontinuity, the discontinuity caused by acoustic impedance is often inconsistent, reflected by the theorem we know, in two different acoustic impedance of the dielectric interface will be reflected. the reflected energy and the size of the interface of the media on both sides of the acoustic impedance of the differences and interfacial orientation, size. Pulse reflection type ultrasonic flaw detector is based on the principles of design.Pulse reflection type ultrasonic flaw detector are mostly A scanning, A scanning display mode that display horizontal axes are in the detected material of ultrasonic propagation time or propagation distance, the ordinate is the reflection of ultrasonic wave amplitude. For example, in a workpiece in the presence of a defect, because of the defect, resulting in defects and material is formed between a different medium between the interface, interface between different acoustic impedance, when transmitting the ultrasonic encountered after the interface reflection occurs, the reflected energy received by the probe, the display screen of abscissa of the certain position will be displayed in a reflection of the waveform, the abscissa, this position is the defect wave in the detected material in depth. This reflected wave height and shape due to defects of different and different, reflecting the nature of the defect.Drill pipe joint and an adapter ( hereinafter referred to as joint ) is an important component of the drillstring in recent years, with Chinas oil industry and the rapid development of industry, joint consumption increases year by year. However, due to domestic joint quality is not high, leading to joint fracture accidents occurred frequently. According to the oil pipe research center in North China, Central Plains, daqing, victory, big harbor, Jilin, Xinjiang and other oil field survey, 1984 1986, domestic joint fracture accident of 100 cases. A large number of joints failure, causing severe economic losses. For example, a Sino-US cooperation in Zhongyuan oilfield drilling team in 1986 April occurred in domestic conversion joint rupture accident, immediate pecuniary loss amounts to about 400000 dollar. According to estimation, the whole nation is annual because the fracture caused economic losses in l00O million yuan to on. Therefore, improving the quality of the weld joint, to reduce early failure, improve the drilling efficiency and the oil industry economic benefits, have very important sense. Joint service condition is more abominable, during use to withstand the tensile, bending, torsion, vibration, shock and other complex loads. According to the joint service conditions, require that the joint has high strength and good ductility and toughness, to achieve this one requirement, abroad in the joint material selection and heat treatment process has taken a series of measures, steel used mainly 4100 series ( Cr Mo ), the main brands are 4l37H, 4l40H etc. Our series of alloy steel basically is from the Soviet Union in the FOCT transplant, and the United States of America alloy structural steel series vary greatly in the GB3077 - 82 although there are Cr - Mo steel were recorded, but the content of carbon and alloying elements ratio and 4100 series differs quite pills are often difficult to replace. The spoon used to produce joint mainly steel 35CrMo for example, carbon, manganese content and 4l37H, 4140H differ greatly, even with high carbon content steel 42CrMo, due to manganese content is low, the hardenability of up to 4140H level. in the aspect of heat treatment process, foreign joint production plant commonly used by controlled atmosphere furnace heating, the inner and outer surface processing after joint bright quenching. Domestic joint heat treatment by ordinary air heating furnace, quenching joint internal and external surface of a large machining allowance, the result of the heat treatment has very big effect. On the domestic joint heat treatment conditions of contrast analysis, domestic joint steel hardenability than abroad have higher requirements. At present, domestic joint steel was in chaos. In addition to some professional production plant using 35CrMo, some local small plant even using 45Mn, 30CrMnTi and so on Hardenability of poor grades, some do not even after heat treatment. In recent years, we from the cuff and collected hundreds of pieces of joint fracture failure samples, the failure of joint analysis shows, most effective belongs to low stress brittle fracture caused by joint low stress brittle fracture are the root causes of poor toughness. The vast majority of fracture joint toughness index C in 30J the following, some less than 10 J. Lose enough analysis also showed low toughness, often with adverse was San tissue corresponding to these joint microstructure called tempered martensite + upper bainite and ferrite or ferrite + pearlite, coarse grain in this description, joint toughness is the ultimate reason materials selection and heat improper disposalForeign joint (mainly the drill pipe joints ) main choice of Japan and the United States, with 4137H or 4140H production of the joints and German states with 36CrNiMo4 production of the joints . 26 only 4100 series joint anatomical analysis results (see Figure 3) shows that, the joint strength index are higher, the average Charpy V notch impact energy Cv 78.5J, vast too much effect joint toughness index C in 54J based on. In 7 36CrNiMo4 joint anatomical analysis results show that, the strength _ labeled with 4137H or 4140H connections are close to or slightly high, toughness index are higher, up to 91.6 J, the C value of all samples in 54J above, fracture morphology transformation wet degrees were lower ( Fo 54J only to account for 3%; strength and toughness index of one in two does not meet the requirements of each accounted for 25.5%; strength and toughness indexes do not meet the requirements for 46%; fracture appearance transition temperature is higher ( FATT o 24 degrees C). Comparative analysis showed, Germany adopted 36CrNiMo4 steel is a joint production of good steel. the domestic use of 35CrMo steel, the heat treatment conditions to meet the performance requirements of joint.From the foreign joint anatomical analysis results, the German 36crNiMo4 joint performance is good, with its high hardenability are closely related. Before the and, due to the domestic joint production conditions, the joint steel hardenability should have higher requirements. Therefore, the steel hardenability should be used as the selection of the main basis. At the same time, should be considered in heat treatment process performance and economy. on hardenability, 40CrNiMo, 40CrMnMo and Germany 36CrNiMo4 closer. From the performance point of view, these materials after proper heat treatment, the routine performance of basically the same. What is different with the low temperature toughness of high nickel steel. From the thermal treatment process performance, 36CrNiMo4 and 4OcrNiMo two steel heat treatment technology is relatively mature, stable performance. From the test results, and CrMnMo steel heat treatment technology is good, can completely meet the requirements of joint performance requirements. and 40CrMnMo in accordance with the circumstance of our country resource, cheap price. Therefore, 40CrMnMo can be used instead of the 36CrNiMo4 and 40CfNiMo joint production. According to the above analysis, 36CrNiMo4 is a joint production of good steel. 36crNiM04 domestic supply shortage situation, available with the circumstance of our country resource 40CrMnMo instead of 36CrNiMo4 joint production. In order to reduce the production cost, to some small size according to the joint ( 127mm ), also can use 35CrMo or 42CrMo steel production.We apply the above research results has introduced to Baoji petroleum machinery factory, peak Machinery Plant and other units, widely adopted. In accordance with our recommended materials and heat treatment process
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本文标题:石油钻杆接头超声波检测方法研究【研究类】【无图】
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