| Circulating fluidized bed (CFB) boiler because of its high combustion efficiency, fuel wide adaptability, energy-saving and so on a series of advantages, in our country’s thermal power industry occupies the important position.High temperature wear of water wall tube has been a significant questions in the operation of a circulating fluidized bed boiler.wear not only bring plants huge economic losses, but also prone to major accidents of improper boiler stop due to wall sudden burst pipes.Laser cladding technique has a high energy density, low dilution,cladding layer binding substrate metallurgical, minimal impact on the workpiece thermal and other advantages, has been more and more widely used in industry. But the research and application of laser cladding technique is also very little on the power plants’four anti-wear technology.Based on operating characteristics of YAG:Nd solid state laser, this paper designs the pipe cladding work table, including motor, transmission, control modules, anti-distortion devices and other components. This paper designs boiler tube anti-distortion device, based on a one-dimensional bar model, analyzes the stress and displacement relationship under the anti-deformation prestressing rod role in boiler tubes,and the theoretical results with the numerical simulation results are compared.The experimental results show that pipe cladding platform design is reasonable, with stable parameters; boiler tube positioning accuracy, demolition is more flexible, which can realize the continuous cladding on 6 m long boiler tube.The use of laser cladding system designed to study the characteristics of Cr3C2-NiCr cladding in different process parameters.The results show that under the optimal parameters,the cladding layer thickness up to lmm, cladding dense and metallurgical bonding to the substrate material.Sampling the wear boiler tube and analyzing the hardness of cladding layer show that within the surface of 700 u. m position, micro hardness is in the range of 1000-1150HV.XRD analysis of the cladding layer showed that the main phase of the cladding layer is Cr3C2, Cr7C3, NiCr. |
