Research On Vibration Control Of Structure-Equipment System Of Coal Preparation Factory With TMD

Industrial workshop is the important place for industrial production,therefore,the structure safety is very important.The workshop structure will damage for many reasons.The vibration because of large power equipment in the industrial workshop working is one of the important reasons that the structure generate vibration.As the important place for coal production,there are lots of large vibrating screen in coal preparation factory.Before the design of coal preparation factory,if designers are lack for considering possible dynamic loading,it is likely to cause the resonance of vibrating screen and structure.The vibration not only affects the normal production,but seriously produces damage to structures.So we need to delve into the vibration of the coal preparation factory and take measures to reduce the structural vibration.This paper studies the vertical vibration caused by vibrating screen working to a steel structure coal preparation factory,and use TMD system for vibration control.Some concrete working contents and conclusions are as follows:(1)In order to understand about the basic situation and the vibration situation of the coal preparation factory,I went to the coal preparation factory for a field test.Firstly we understood about the project summary,including the type of structures,size of column section and beam section,the layout of the vibrating screen,and the work frequency of vibrating screen,etc;Secondly we selected the test method and test equipment,and made the four vibrating screens at 9.7m floor working together.We collected the vibration response from the 38 measuring points are selected at 4.7m floor and 9.7m floor.Finally,We processed data,and got the first order modal frequency as 15.63 Hz close to working frequency of vibrating screen as 15.83 Hz,so probably floor vibration caused by resonance vibration.To analyze acceleration time history curve and displacement spectrum curve of measuring point,we found the vibration near vibrating screens was larger,and the acceleration response was in excess of the building vibration acceptable limit by Japan which was 1.02m/s2;(2)Refer to the steel frame factory,building the modal analysis,harmonic response analysis and transient analysis under the equipment vibration based on ANSYS.We got the vibration displacement peak between 14 Hz and 15 Hz and found the resonance frequency was at 70% 125% of the factory main equipment working frequency,which was identical with the field test result and revealed the reasonfor great vibration at local area of the plant was resonance caused by equipment vibration further.(3)We set TMD system for structural vibration control in the form of suspension below the floor.after used the Den Hartog method to determine the parameters of TMD,We made the harmonic response analysis and transient analysis for each node.We could know that after the TMD damping,the vibration displacement peak and acceleration response obviously decreased,and met the vibration prescribed limit,and its frequency was about 10 Hz,which avoided the resonance region.So vibration reduction with TMD system achieved the target this time.