Experimental Study On Erosion Wear Behaviors Of Fluoroplastic-steel Composite Tubes

The adoption of fluoroplastic-steel composite tubes heat exchanger can slow down the problems of corrosion and ash deposit in the process of using metal heat exchanger,and realize waste heat recovery deeply in power plant.However,the wear conditions of composite tube concern the efficiency and working life of this kind of heat exchanger.Experiments were carried out to study on the erosion wear behaviors of two kinds of fluoroplastic-steel composite tubes,and could provide the data references for the practical use of fluoroplastic-steel composite tubes heat exchanger.The solid particle diameter distribution and component were measured and solid particle micro morphologies were observed.The tensile properties,thermal expansion properties,hardness and anti-temperature change properties of fluoroplastics were tested.Then,a wind tunnel erosion wear experimental facility was builded.Erosion wear experiments were carried out using the facility.The study focused on the influences of the velocity and temperature of air and the particle mass concentration on the solid particle erosion rates of two kinds of fluoroplastic-steel composite tubes under two kinds of particles respectively,those were coal ash and referential particles.In addition,the mechanism of erosion wear of composite tube was discussed by observing the surface morphologies through scanning electron microscope.Finally,3×3 composite tube bundles erosion wear experiment was conducted.Experimental results show that nearly a good power function relationship between erosion rates of two kinds of fluoroplastic-steel composite tubes and the velocity of air with the velocity at medium-low speed ranges.The erosion rates are also approximately proportional to the particle mass concentration.The erosion rates decrease as the temperature of air increases.The morphologies show that the surface of two kinds of fluoroplastic-steel composite tubes mainly happen plastic deformation and microcrack locally with particle impacting vertically,and happen cutting together with ploughing with particle impacting obliquely.