井下钻具金刚石止推轴承组振动特性研究  

Study on Vibration Characteristics of Diamond Thrust Bearing Pack in PDM assembly

作　　者：张伟 王瑜[1] 孙健越 张凯 孔令镕 Zhang Wei;Wang Yu;Sun Jianyue;Zhang Kai;Kong Lingrong(School of Engineering and Technology,China University of Geosciences(Beijing)/Key Laboratory of Deep Geological Drilling Technology,Ministry of Natural Resources)

机构地区：[1]中国地质大学(北京)工程技术学院,自然资源部深部地质钻探技术重点实验室

出　　处：《石油机械》2021年第8期1-7,共7页China Petroleum Machinery

基　　金：国家重点研发计划“深地资源开采”专项课题“小口径高效系列钻具研究”(2018YFC0603404);国家自然科学基金面上项目“基于高密度钻井液的高温涡轮取心钻进模型研究”(41872180);中央高校基本业务费优秀教师基金项目“全金属动力钻具水力部件旋转振动模型研究”(292018093)。

摘　　要：金刚石止推轴承组是井下动力钻具的重要组成部分。为研究实际钻进过程中金刚石止推轴承组的振动特性,分析振动信号对金刚石止推轴承组的影响,首先通过试验测试的方法获得金刚石止推轴承组的频谱图并确定金刚石止推轴承组的共振频率;而后对实际钻进工况进行简化,分析实际工况中存在的振动类型,并在实验室条件下创造这些类型的振动信号。通过试验分别观察周期性振动信号对不旋转状态下金刚石止推轴承组的影响以及模拟地层钻进条件下阶跃型振动信号对旋转状态下金刚石止推轴承组的影响。试验结果表明:试验样本整体的共振频率为50、90和189 Hz;考虑到螺杆马达的转速影响,对轴承组在40~70 Hz、80~100 Hz区间振动响应振幅变化的趋势进行试验分析可得,在实际工况中轴承组内外圈振动同步性较好,但在不同频率下响应幅值相差较大,在研究过程中需将轴承组的内外圈分开进行分析;模拟实际钻进过程中,振动信号的试验验证了PDC钻头在切削过程中存在大切削和小切削的现象。研究结果可为金刚石止推轴承的推广、普及以及设计改进提供试验数据支持。Diamond thrust bearing pack is an important part of mud motor.In order to study the vibration characteristics of the diamond thrust bearing pack in actual drilling and analyze the influence of vibration signals on the diamond thrust bearing pack,in the paper,the test method was used to firstly obtain the frequency spectrum of the diamond thrust bearing pack and determine the resonant frequency of the diamond thrust bearing pack;then,the actual drilling behavior was simplified to analyze the vibration types existed in actual working conditions,and these vibration signals were subsequently created under laboratory conditions.By means of test,the effect of periodic vibration signal on the non-rotating diamond thrust bearing pack and the effect of step vibration signal on the rotating diamond thrust bearing pack under condition of simulating formation drilling were observed respectively.The test results show that the overall resonant frequencies of the test samples are 50 Hz,90 Hz and 189 Hz;considering the influence of rotary speed of screw motor,the test and analysis on the amplitude variation trend of vibratory response of bearing pack in the range of 40~70 Hz and 80~100 Hz show that in actual working conditions,the vibration synchronism of internal and external rings of the bearing pack is good,but the response amplitude varies greatly under different frequencies,therefore,in the research process,the internal and external rings of the bearing pack need to be analyzed separately;and in the simulation of actual drilling,the vibration signal test verifies that the PDC bit has the phenomenon of large cutting and small cutting in the cutting process.

关 键 词：金刚石 止推轴承组 振动模型 共振 周期性振动 锯齿形振动 

分 类 号：TE921[石油与天然气工程—石油机械设备]