| With the continuous improvement of the HSE management system in the oil field operation,the problem of driller’s fatigue in workover rig has attracted more and more attention.In order to explore the fatigue characteristics of human body during the driller operation,this paper analyzes the muscle load change during the operation of the brake handle by combining simulation analysis and the s EMG test method from the perspective of biomechanics.A quantitative model of the fatigue degree based on s EMG is established.In order to screen out the key force muscles of the human body under the specific drilling operation,the drilling operation and fatigue cause of the workover rig are analyzed,and the brake operation with heavy workload and high frequency is selected as the research object.Considering the cumulative effect of time,the muscle load intensity function is introduced and taked as the evaluation index of the working fatigue.Muscle grouping is performed from the whole to the local.The trend of muscle load is analyzed step by step through the reverse dynamics simulation.The fatigue degree of each muscle in a certain period of time is calculated,and finally three key muscles of deltoid muscle,biceps brachii muscle and triceps brachii muscle are selected.Then,the s EMG test of brake operation is carried out on the XJ70 workover rig test bench,the s EMG of each key muscle is collected and analyzed respectively in time domain and frequency domain.The change of each characteristic parameter index is observed,and the characteristic parameter index RMS which can better characterize the fatigue of operation is extracted through comparative analysis.On this basis,the muscle load intensity is calculated,the influence factor of the working posture on the fatigue caused by backrest inclination is explored,and the quantitative model of the fatigue degree of the upper limb based on the s EMG is established.The research results can be used to guide the selection of working posture and the optimization design of seat parameters,which has certain practical significance for delaying working fatigue and improving the efficiency and safety of the work. |
