Development Of Double Wire Welding System For Arc Rapid Prototyping And Forming Technology

The arc rapid prototyping technology is a technology that relies on arc melting of metal welding wire and performs rapid stack forming according to a set trajectory.The formed part has the advantages of good mechanical properties and high density,and has great potential for development.In order to improve the dimensional control accuracy of the arc rapid forming and the surface quality of the formed parts,this research has carried out the research on the arc rapid forming double wire welding system and double wire forming technology.Firstly,the improvement of the welding equipment and the design of the double wire welding torch were carried out.A set of thin wire feeding equipment was added to the welding system,and two sets of wire feeding systems were controlled using PLC.In order to meet the working requirements of the arc rapid prototyping double wire welding system,an integrated double wire welding torch is designed.The welding torch can use two different diameters of wire for forming work,and the thin wire feeding mechanism is integrated into the welding torch to improve the integration of the forming system.Then the control program was written,control program judges the working status of the two wire feeding mechanisms through the relationship between the current wire feeding speed and the speed threshold value.During the forming process,the system can increase or decrease the wire feed speed thick the touch screen.When the wire feed speed reaches the speed threshold,the wire can be switched.After the design of the arc rapid prototyping double wire welding system was completed,two different diameter wire forming experiments were conducted to investigate the effect of welding parameters on the forming profile.Comparing the size of the weld formed by the thin wire and the thick wire,when the actual wire feed speed of the filament reaches 3.0 times the set wire feed speed,welds are the most similar in size under the same parameters.Maintaining the ratio between the actual wire feeding speed and the set wire feed speed,carry out an alternating forming experiment in which a wire is accelerated before the other wire is decelerated,to investigate the influence of the length of delay of decelerate on the formation of the weld during the welding wire switching process.When the deceleration delay is short,the formed weld seam will have a defect of concave and convex.When the deceleration delay reaches 60%of the total length of the switching process,a beautiful appearance of the weld seam can be obtained.As the deceleration delay continues to increase,there will be convex defects in the weld.Using well-formed deceleration delays,alternating parameters of double wire with gradual change parameters and single change parameters were used to verify the suitability of this deceleration delay under alternate forms of other forms,and through experiments,it can be obtained that the forming weld with beautiful appearance can be obtained under this deceleration delay.