Study On The Process Of Slurry Blasting Of Removing The Oxide Layer

“Pickling descaling”is a common method for strip descaling,traditional pickling descaling technology has some shortcomings,such as environmental pollution and human health hazards.At present,shot blasting is an advanced descaling technology,which has high processing efficiency and wide application,but it will cause a lot of dust pollution.Based on the advantages of shot blasting technology and avoiding dust pollution,shot blasting descaling technology has great potential in replacing acid pickling and shot blasting descaling technology.In this paper,the related technological parameters of abrasive slurry are analyzed through theoretical analysis,simulation and experiment,and the influence law of strip surface descaling is studied.On this basis,the special experimental device for descaling is optimized,so as to provide reference for the research and application of descaling.The main research work is as follows:(1)According to indentation fracture theory,the erosion and fracture mechanism of abrasive on brittle iron oxide scale is analyzed;the plastic shear of abrasive on matrix material is studied;and the crack propagation mechanism of "water wedge effect" is studied.The velocity model of abrasive in moving process is studied by abrasive particle size,mass and blade speed.The impact force model of abrasive on workpiece surface is studied by abrasive velocity and pit depth,which provides theoretical basis for subsequent results analysis.(2)The Fluent software was used to simulate the influence of the projection distance,impeller speed and abrasive particle size on the characteristics of the jet flow field in the process of descaling,and the rule of the influence of the process parameters on the surface pressure and velocity of the workpiece was obtained.The influence law of abrasive particle size and ejection time is consistent with the experimental results.(3)Through contrast experiments of blasting and shot blasting,it is concluded that the blasting method has a higher descaling rate and a smoother surface.The influence of abrasive particle size,ejection distance and ejection time on the descaling rate,surface morphology,surface oxygen content and residual stress were obtained through the experiment of ejection descaling.(4)On the basis of relevant theory,simulation and experiment,aiming at the uneven mixing of abrasive and water in the experiment,the structure installation and feeding system of the jet pump of the slurry throwing test-bed were optimized and improved.Through the above research,the different effects of shot blasting and blasting on metal surface erosion are obtained,and the influence rules of each technological parameter on metal surface erosion in the process of blasting descaling are basically mastered,which provides certain theoretical basis and technical support for the development of green environmental protection intelligent descaling device.