【作者】 张海凤；

【导师】 杨敬源； 杨超；

【作者基本信息】 大庆石油学院 ， 机械设计及理论， 2003， 硕士

【摘要】 在我国，钻机底座的设计实际上是以静力强度加经验为主要设计依据，较少或根本没有考虑结构的动态特性，致使某些钻机底座在实际工作过程中，其固有振动频率与钻井设备的工作频率重合或接近，导致这些钻机底座出现较强烈的振动，使钻机底座的工作状况和受力更加恶劣、复杂，降低了钻机底座的使用寿命，同时也增加了工作过程中的危险性。所以改进钻机底座的设计或对现役钻机底座进行动力修改以改善其动态特性，很有必要。 但是，不同类型钻机的底座具有不同的结构形式，即使是同一类型的钻机，其底座结构也会不同。要想了解各种钻机底座的动态特性并加以利用，势必要进行大量的试验，但由于现场工作环境及生产要求的限制，进行多次试验存在很大困难，再加上恶劣环境对测试工作的影响，所得结果的精度和可靠程度也会降低，采用模型在室内进行模拟试验则可避开这些不利因素。 在试验设计部分中，通过对底座的结构和振动情况进行分析，根据目前的振动情况和现有的试验设备确定了底座振动测试的试验方案。该试验根据激振力的施加方向分三组进行，分别为水平横向、水平纵向和垂直方向的振动，并在模型上布置了相应的测点。 底座测试分析以DASLab软件为分析平台，开发46通道实时并行大容量动态信号采集分析系统，通过传递函数分析、模态分析及功率谱图分析，得到底座的一些模态方面的数据，这些数据为以后有限元的分析提供了重要的依据；底座振动分析主要在开发Algor FEAS软件的基础上，以空间梁单元作为有限元计算的基本单元，通过使底座空间结构数值化，建立底座计算机数值模型，分析得到其模态参数。 在上述工作的基础上，本文通过对底座(ZJ-15)进行测试分析和有限元分析相结合，得到底座的振动特性，对于有限元模型，采用局部修正理论来进行修正，使之逼近于底座的真实结构，然后通过计算机载荷模拟试验来求得其振动情况，并进行动态设计。在进行动态设计时，根据影响底座振动的几种情况，在有限元模型上进行修改试验，对得到的新振型进行分析，从而了解底座的振动变化情况，得出对底座设计有意义的结论。更多还原

【Abstract】 In our country, rig substructure is designed mostly on the basis of its static strength and designer’s experience, and its dynamic characteristic is usually taken no account. As a result, the rig substructure vibrates violently when its nature frequencies close or equal to the working frequencies of the drilling equipment, which deteriorates the substructure’s working status, shortens its lifetime and makes the working process dangerous. Thus, it’s necessary to improve the design of rig substructure or better the dynamic characteristic of substructure that is being used by dynamic modification.But, different kind of rigs have different substructure styles, and the rigs of same kind have different substructure frameworks, too. A lot of tests are required if the dynamic characteristic of the substructure is to be known and used. But it’s very difficult to proceed lots of tests because of the restriction of field environment, and the influence of atrocious environment on testing can depress the precision and reliability of results. The disadvantageous factors mentioned above can be avoided by simulation tests in lab on model.In the experimentation, through analyzing the frame and vibration of substructure, the author ascertain the experiment project of the substructure vibration test which dependents on vibration status at present and trial equipment in existence, the experiment is divided into three groups according as the stimulation’s direction, which are cross direction horizontally, longitudinal direction horizontally and direction perpendicularly, and dispose stimulation drop on the mode.Based on the DASLab analysis platform, mass parallel real-time Acquisition Analysis System having 46 channels was developed for dynamic signal, according to analyzing transfer function analysis, modal analysis, power spectrum analysis, we can get some data about mode, which was important evidence to afterward FEA analysis. In the vibration analysis for substructure, firstly AlgorFEAS was developed. After it, by adopting the three-dimensional beam element as the basis element for FEA analysis of substructure structure, the author established the computer numerical model to analyze the mechanical parameters about model. In the measure analysis for substructure.Based the foregoing work, combining measure and FEAS analysis for substructure, this thesis get the characteristic vibration. For the FEAS, the author presented an theory of matrix spectrograph to modify the model of FEA, so as to the real structure of substructure in use, and then through computer loading simulation test to get the vibratility, and carry through the dynamic design. When the design carried through, according to some things that affect rig substructure’s vibration, The author tries out modification test to the FEA model, and analyzes the new dynamic figure, so we can know the change thing of rig substructure and get the significative conclusion to the substructure.更多还原