Failure Analysis And Improvement Of Planetary Reducer For Cutting Department Of Shearer

The work environment of Coal winning machine's is extremely complex and unstable,when the coal winning machine through the rock fault,cutting rock last for some time,the load increased,the output torque of cutting of planetary gear reducer is equal to the drum of drag torque.Working in this condition for a long time may cause damage to the parts of the planetary reducer.As an important part of the transmission system of the cutting part,the planetary reducer will seriously affect the normal operation of the shearer.In order to check whether the key components of the planetary reducer meet the work requirements under this condition,carrying out the following work for MG300/755-WD coal winning machine.The output torque of the planetary reducer is equal to the resistance moment of the drum,and the resistance of cutting resistance to the drum axis is applied to the transmission system of the planetary gear reducer.During the working process of the drum,the position Angle of the cutting gear will be changed,and the number of cutting teeth involved will also be changed,so the output torque of the planetary frame is change.That shearer fault rocks,the maximum current is greater than the rated current of the collected,indicating that coal winning machine cutting rock and coal gangue,working current is greater than the rated current,when the coal winning machine working current reaches 1.2 times the rated current,the coal winning machine will stop working,and it will be 1.2 times the rated current of the corresponding torque as the maximum output torque of planet carrier,When we do stress analysis and fatigue analysis,modal analysis with the planet carrier,it is concluded that the strength of the planet carrier to meet the work requirements,working frequency is far lower than the first order frequency,resonance will not occur,but the working life is lower than the design life,fatigue damage is the planet carrier the cause of the malfunction.The contact stress analysis and fatigue analysis of the planetary wheel and the planetary wheel and the inner gear are satisfied with the working requirements of the strength and the life span.The stress analysis results of the planetary frame show that its strength meets the requirements of the work,and the fatigue analysis of it shows that the working life of the planetary frame is lower than the design life,and the planetary frame cannot work properly.Planetary frame on the left side of the board remains the same,increase the thickness of the plate on the right side,rebuilt model 12 times,increasing 1 mm everytime,carries on the stress analysis separately,find out the maximum stress value of the smallest group,the increase of thickness of 7 mm.The planetary frame on the right side plate thickness unchanged,the increase on the left side of the plate thickness,increase 1 mm everytime,rebuilt model 12 times,find out the maximum stress value of the smallest group by stress analysis,the increase of the thickness of 6 mm.At the same time,the thickness of the left and right sides was increased by 6mm and 7mm,and the stress analysis was conducted.Compared with the above two groups,the results showed that the effect was best when the left panel was increased by 6mm.Therefore,the improvement plan increases 6mm to the left board,and verifies its feasibility through fatigue analysis and modal analysis.