Research On Technology And Mechanism Of Additive Manufacturingof Upstream Pumping Mechanical Seal Ring

The upstream pumping mechanical seal is a fluid-lubricated non-contact mechanical seal,which truly realizes zero leakage of the medium and zero pollution of the environment.It is an indispensable component in fluid machinery and power machinery.The fluid dynamic pressure seal groove on the seal ring is a key component that affects the performance of the upstream pumping mechanical seal.The groove structure is complex and very shallow,the groove depth accuracy is very high,and the seal ring is mostly hard,such as ceramics,hard alloys,etc.Material,general machining cannot be completed.This paper presents a method of additive electroplating nano-ceramic powder additive manufacturing upstream pumping mechanical seal ring,and conducts in-depth research on nano-composite electroplating mechanism,and has obtained some innovative research results.The ligand field theory was used to study the complexes of nickel ions and the adsorption structure and properties of nano-SiC particles.The space configuration was studied and the existence of nickel ions and SiC particles in the composite bath was determined.Electrochemical reaction,ion discharge,crystallization nucleation and growth of the composite deposition are analyzed and discussed in depth,which lays a theoretical foundation for the additive manufacturing of upstream pumping mechanical seal rings.A Ni-SiC composite deposition interface model was proposed and the kinetic equation of the composite deposition was established.Based on the established dynamic equations,the simulation software COMSOL was used to simulate and analyze the composite deposition electric field and flow field,and the best electrode shape and flushing method were obtained.Ni-SiC nanocomposite deposition additive formulations have been developed through optimization.Studies have shown that the coating obtained from the additive formulation has excellent bonding strength,surface roughness and microhardness.The preparation method of Ni-SiC composite plating solution was analyzed and studied,and the optimal particle dispersion method of ultrasonic vibration plus mechanical stirring was obtained.The effects of the hardness,bonding force,particle content and deposition rate of the silicon carbide particles with 500 nm and 5?m particle sizes at different concentrations were studied,and the optimal composite bath formulation was obtained.The electrochemical behaviors of the common plating solution and the composite plating solution system were studied,and the influence of nanoparticles on the electrocrystallization process was obtained.The developed composite plating bath was used for process testing,and the effects of current density,pH of the plating solution,stirring speed,and temperature on the coating performance were studied,and the corresponding relationship between the effects was obtained,and the additive manufacturing upstream pumping was obtained.The best process conditions for mechanical seal rings.For a centrifugal pump with an internal diameter of 30 mm,a spiral groove type mechanical seal ring end surface structure was designed,and an upstream pumping mechanical seal ring face groove machining method was studied.An upstream pumping mechanical seal ring was experimentally processed to effectively solve the seal.The hydrodynamic seal groove on the ring is difficult to process.