The Research On Influence Of Center Support Structure On Performance Of Beam Pumping Unit

Oil pumping unit is an important working machine in oil field production.When the drilling is completed,the oil pumping unit starts to extraction oil.At present,the conventional beam pumping unit is most widely used.However,with the development of pumping units,the beam pumping unit Developed by company of American Lufkin different from the beam pumping unit developed by Lan Shi in the structure.The main difference is the central support(also known as beam support)and tail support.Therefore,the different structures of the two pumping units has become the focus of research work in China,this paper research the function of different structure of central support of pumping units.First of all,made a force analysis of the central support of pumping unit.Taking C-456D-305-144 type pumping unit as an example,establish a mechanical modle based on performance parameter,physical dimension,tructure and operational principle.Then carry on the dynamic analysis,the dynamics analysis to the load of central support by Matlab was developed.Secondly,made analysis for the bearings of the important components of the pumping unit center support,analysis the influence of different structure when injection lubricating fluid.Then calculated the bearing load,the number of the loaded roller and the radial displacement of the bearing in the moving period of two pumping unit according to the Hertz contact theory and the different parameters of the two kinds of bearings.The vibration signal that analysis of the two types of bearings analyzed in time domain and frequency domain,then analyze vibration signal,extracted the component of rolling bearing fault information.Then the envelope demodulation of the first component is carried out by using Hilbert Technology,gained the envelope spectrum of fault signal,finding the characteristic frequency of the peak value from the envelope spectrum.Comparing the characteristic frequency of the two types of bearings,comparing the failure degree and fault type.Finally,according to the finite element analysis of the key components of the central support,the maximum stress part is located at the central support.Then made finite element modal analysis and fatigue reliability analysis for center supported spindle.Based on the analysis,the influence of load on the fatigue reliability of the central support spindle is obtained.Thus,the beam pumping unit in the central support structure: "Lufkin" structure is better than "Lanshi" structure.