Research On Remanufacturing Of Key Vulnerable Parts Of Ultrafine Pulverizer

Ultrafine crusher is widely used in food,mining,chemical industry and other fields.As a key vulnerable part of the hammer blade,a large number of parts need to be replaced every year.Most of the broken hammer blade is sold as waste,causing serious waste of resources.With the country’s policy of establishing a resource-saving society,remanufacturing technology has developed rapidly.There are some disadvantages of traditional repair methods,and laser cladding remanufacturing has been widely favored because of its advantages such as shape control,high performance of parts after repair,and green pollution-free.This paper mainly studies the remanufacturing of hammer cladding laser cladding.First,reverse engineering is used to complete the data collection,processing and 3D reconstruction of the damaged part.The second is the planning of the laser cladding path of the damaged part of the hammer blade and the selection of the best process parameters.Finally,the laser cladding experiment is completed and the quality of the laser cladding is checked.The detailed research contents and conclusions are as follows:(1)Reconstruction of the 3D model of the damaged part of the hammer headThe first is the acquisition of three-dimensional reverse data.The advantages and disadvantages of non-contact measurement and contact measurement are compared and analyzed.Combined with the characteristics of the hammer blade part,non-contact measurement is finally selected.Secondly,professional point cloud processing software is applied to the point cloud to remove external solitary points,remove noise,and repair holes and other data.Finally,the three-dimensional model of the standard hammer blade is imported and aligned with the damaged hammer blade after a series of transformations to obtain a model of the damaged portion of the hammer blade.(2)Laser cladding path planningLaser cladding path planning mainly includes three parts: threedimensional model slicing,scanning and filling path planning,and robot cladding path control.The first part of the three-dimensional slicing of the three-dimensional model mainly introduces the principle of slicing and the study of the main algorithms.Finally,it explains how to use related software to complete the slicing.The second part of scanning filling path planning mainly introduces the current scanning path planning methods.According to the characteristics of the damaged part of the hammer blade,the composite scanning filling method is used to plan the scanning filling path.The third part of the robot cladding path control mainly introduces some basic coordinate systems of the robot and how to use the coordinate transformation and kinematics to realize the robot motion control.Finally,the programming method of the robot trajectory control is briefly introduced.(3)Selection of laser cladding materials and selection of optimal process parametersIn the process of material selection,the laser cladding powder is firstly analyzed,and four kinds of powders,Fe55,Fe60,Ni55,and Ni60 are selected.Secondly,the laser cladding equipment is briefly introduced and the selected powder is subjected to a dichotomy experiment.Finally,Fe60 was selected as the cladding material by cladding layer binding and hardness testing.In the process of selecting the best process,the main process parameters that affect the quality of laser cladding are analyzed first.Secondly,a single-level cladding experiment with five levels and four factors is designed to analyze the effects of laser power,scanning speed,shielding gas flow,and powder feed rate on the cladding layer width,height,penetration depth,and dilution rate.The results are analyzed.It is shown that the laser power and scanning speed have a greater impact on the width and height of the cladding layer,while the powder feed rate and shielding gas flow have a smaller effect on it,but the powder feed rate has a greater impact on the penetration depth and dilution rate.By comparing and analyzing the surface quality,microstructure and hardness of the sample,the laser cladding power is 1800 W,the scanning speed is 10 mm / s,the protective gas flow is 800 L / h,and the powder feed rate is 50 r / min.parameter.Finally,the best parameters of a single cladding were used for multiple overlap experiments,and the surface quality and microhardness were analyzed,and the optimal overlap rate was 40.63%.(4)Hammer knife laser cladding experiment,cladding quality inspection,economic analysisThe laser cladding experiment process of hammer blade is introduced,including pretreatment of broken hammer blade,layered slicing of model,and offline programming of robot trajectory.Laser cladding quality testing mainly includes surface quality testing and friction and wear performance testing.The test results show that the surface hardness value of the repair area ranges from 53.8HRC to 58.2HRC,which meets the hardness requirements,the friction coefficient is less than the substrate,and the stable wear time is longer than the substrate.Meets standard parts requirements.Finally,the cladding economy is analyzed,and the analysis shows that hammer cladding laser cladding remanufacturing saves a lot of costs every year and meets the economic requirements.