Design And Test Of Cutting And Separation Device Of Residual Film Mixture Based On Conveying Of Water

To solve the technical problem is difficult to separate and recover impurities such as membrane and cotton stalk directly due to intertwining among the main components of membrane miscellaneous mixture recovered mechanically in Xinjiang cotton field.Based on the differences in the size,shear characteristics,and suspension characteristics in water between the main components of membrane miscellaneous mixture and cotton stalk,a new method of swirl sedimentation and cut-film filtration and impurity removal under the negative pressure of the water pump was put forward in this thesis.At the same time,complete the water suction,shearing,separation,and recovery of the membrane mixture.The main research contents were as follows:（1）Experimental research on the shear characteristics of film-stem mixture:Collected the mixed mixture of machine-received film through field investigation,manually separated and determined the physical parameters of its main component,cotton stalk,and plastic film,and explored the relationship between the number of layers of plastic film wrapped around the cotton stalk,the diameter of cotton stalk,loading speed and shear strength through the combination test of three factors and three horizontal centers of the shear characteristics of film-stem mixture,The response model of the main component of the mixed mixture of plastic film and cotton stalk（the number of layers of plastic film and cotton stalk）and its shear strength was established,which provides a theoretical basis for the design of the film cutting and impurity removal mechanism.（2）Experimental research on suspension characteristics of film-stem mixture:Observed and tested the suspension characteristics of film-stem mixture through the film-stem suspension hydraulic characteristics test rig,observed the track and posture changes of the main components of the machine-received film-stem mixture,the film and the cotton stalk in the water movement process,explain the difference of the suspension characteristics of the film and the cotton stalk.（3）Design of membrane miscellaneous shear separator based on conveying of water:According to the principle of negative pressure conveying of water pump,settling separation and the difference of size and shearing characteristics of main components of membrane miscellaneous mixture,cotton stalk,a new method of rotating current settling and cutting film filtration and impurity removal under negative pressure transfer of water pump was put forward,the overall scheme design was completed,and the theoretical analysis and parameter design of key components were carried out.（4）Research on the theory of cutting film and removing impurities based on conveying of water:Physical model of cotton stalk and ground membrane were established according to slender body theory and spherical fiber particle model by consulting literatures.The theoretical analysis of membrane cutting and impurity removal process was carried out,the stress model of membrane during suction and cut stage and the force model of cotton stalk during filtration and drainage stage were constructed,and the relationship between the structure parameters of hybrid removal knife,filter fixing knife and the operating parameters of the device was revealed.The dynamic trajectory equation of the effective cutting edge line of the removal hybrid cutter during the process of film cutting is established,and the trajectory of the film under the joint action of the movable fixed cutter is obtained by combining the trajectory equation of the involute slit of the filter fixed cutter with the trajectory equation of the movable fixed cutter.（5）Experimental research on membrane cutting and impurity removal:A test device for membrane impurity shear separation device based on conveying of water was established,The orthogonal test of three-factor,three-level quadratic regression was carried out,and a multi-objective response surface regression model was established,which was optimized and verified by experiments.The results show that the order of primary and secondary factors influencing the pass rate of broken film is the rotational speed of the movable knife,the gap width of the fixed knife and the radius of the movable knife wall.The order of primary and secondary factors influencing the crushed film rate is the rotational speed of the movable cutter,the radius of the movable cutter wall and the gap width of the fixed knife.For crushed film impurity rate:the rotational speed of the movable cutter,the gap width of the fixed knife and the radius of the movable cutter wall.When the rotating speed of the movable cutter is 954 r.min^-1,the gap width of the fixed knife is2.8 mm and the radius of the movable cutter wall is 80 mm,the crushed film rate is 88.80%and the crushed film impurity rate is 7.51%.The relative error between the optimized test result and the predicted value of the model is less than 5%.The main conclusions can be used as a reference for the study of cutting and separating methods and equipment of the machine-collected film and impurities.