Research On High Efficiency Flat Position Welding Process Of Moderate Thick Plate And Establishment Of Welding Database

Medium and thick plates are widely used in mechanical engineering,bridge construction,petrochemical and marine engineering,and their usage accounts for about 10% of the annual steel usage,and it is on the rise.At present,the welding methods used in the production and use of medium and thick plates are mainly manual arc welding,supplemented by melting pole co2 gas shielded welding,and welded by submerged arc welding in some flat positions.In the first two welding methods,the metal cladding efficiency is low,the welding quality is unstable,the production time is long,the heat input of submerged arc welding is too large,it is difficult to use on the high strength steel with high welding quality,and the welding method is limited and can not be used in full position welding.The current medium thickness plate welding process should not be suitable for the application and development of medium thickness plate,which restricts the working efficiency in the field of medium thickness plate production and use.Double wire welding has the advantages of simple preparation before welding,stable process parameters and large metal cladding.Laser arc composite welding has great advantages in non-ferrous metals and other materials which are sensitive to heat input.The two ways to improve the welding efficiency by increasing the metal cladding and welding speed are suitable for the application of medium thick plate.In addition,due to the variety of welding methods,different material grades,multi-layer and multi-pass welding,the complex welding process leads to the jumbled information of parameters.By establishing the welding database,the welding parameters can be effectively classified and sorted,which is convenient for experimental research and field use.A double-wire welding test was carried out on 30 mm carried out in this paper.In the course of mechanical properties test,it was found that the side bending performance of the weld was poor,and the main reason was that the side wall of the bottom layer was not fused and the fusion depth was small,which resulted in the weld cracking at the side wall of the bottom layer.With the analysis of the change of welding wire current,back welding wire current,welding speed and butt gap,the influence of each parameter on the fusion depth of the bottom weld side wall is obtained.Compared with single mag welding,the welding efficiency is increased by 80%.Based on the results of previous test and analysis,the practical application of double wire welding method in production site is carried out.The test of 9 long weld m welded at one time proves the applicability of the method.Laser arc composite welding technology is used to study the welding technology of 18 mm x80 steel plate,and the technological characteristics of laser arc welding method are analyzed.The welding speed of 1.2 m/min is realized,and the welding efficiency is 100%higher than that of traditional single mag.In addition,the influence of each parameter on weld forming is analyzed,and the parameter that has the greatest influence on welding joint forming is the butt gap,and the empirical formula of swing welding is summarized according to the experimental results.In terms of welding database,access database management software is developed under the windows operating system.Through the classification of the welding information and analyzing the database,the plate welding database system is designed,which can meet the safe use of different users.The system is developed by the combination of database and algorithm model,mainly deleting and checking welding process parameters,image display,permission login,safe backup,etc.On this basis,the method of embedding bp neural network algorithm in database realizes real-time,efficient and accurate parameters calculation with data in database and can predict new welding process parameters.