The Galvannealed(GA)-coated sheets are subjected to cold rolling deformation, and the changes in the morphology, element distribution and corrosion resistance of the GA coating at different reduction rates are explored. The results show that the original coating before rolling is mainly composed of δ(FeZn7) and Γ(FeZn10) phases, and a free Zn layer with loose distributed holes is found on the surface of the coating. The holes are deformed into needle shape along the rolling direction, and the density gradually decreases. When the reduction rate is greater than 40%, the needle-like micro-holes disappears. With the increase of cold rolling reduction rate, the thickness of the coating layer decreases continuously, and the hardness of the coating layer and the substrate increases. When the reduction ratio is larger, the interface presents a zigzag shape. The change of reduction rate has little effect on the distribution of Zn and Fe elements, and there is an iron-rich diffusion layer at the interface between the coating and the substrate. When the reduction rate is greater than 20%, the coating is broken to a certain extent, and a small amount of O element begins to exist at the interface of the coating and the substrate. The weight loss of GA coated sheet under corrosion tends to be gentle with the increase of time, and the difference of loss weight between different reduction rates is small, and the coating after rolling still protects the substrate well.

This paper described the phenomenon of punching delamination of hot-rolled steel plate 700L for frame side rails and its harm. Through macro and micro observation, combined with the blanking process principle, the factors of material, process and mechanism that lead to delamination in punching were analyzed. It is believed that severe plastic deformation during punching leads to serious fibrosis of the structure, and the fibrous structure delaminates or breaks under the action of shear stress and normal stress, forming a competitive mechanism with the generation and expansion of main cracks in the tear band. If the delamination and fracture of the fiber occur later than the crack of the tear band, the delamination or serrated fracture on the surface of the punched hole can be prevented. Using Theory of Inventive Problem Solving(TRIZ) theory, the prestressed punching process is designed and developed, which not only ensures the integrity of the punched hole surface, but also ensures the punch life.

Based on the Dongfeng vehicle project, the conformal cooling channel consistent of the circuit board shell was established. The effect of the conformal cooling scheme was analyzed by MoldFlow and ANSYS, and compared with the traditional cooling scheme. Finally, the metal 3D printing process was used to fabricate the mold kernel and the cooling channel, which was verified on the injection mold. The results show that the conformal cooling scheme greatly improves the injection efficiency and reduces the deformation of the product.

To effectively solve the knotty problem regarding anti-corrosion design, management and control during vehicle development, this paper applied the Concurrent engineering concept of integrated design of material, structure, process and performance, and decomposed the vehicle anti-corrosion characteristics into subsystem anti-corrosion characteristics and parts performance index, then evaluated the achievement of indicators and formulated development plans, controlled comprehensively the whole anti-corrosion design process using diversified technical methods and cross departmental linkage and coordination mechanisms, boosted the coordinated development of corrosion characteristics, aging and other related characteristics of paint coated parts and improvement of anti-corrosion technological standards, promoted the anti-corrosion design capability enhancement of vehicle system, eventually upgraded vehicle durability steadily.

Projection welding of M12 ring convex welding nut and 2.5 mm thick plate has the defect of faulty welding, using energy storage welding machine in place of power frequency convex welding machine can solve the defect of faulty welding. There is an optimal combination of welding voltage, tempering voltage and welding pressure in the welding parameters of the energy storage welder. The orthogonal test is suitable for optimizing the optimal welding parameters. The optimized parameters (welding voltage 650 V, tempering voltage 650 V, welding pressure 16 kN) were used for test welding to obtain a convex welding joint with ejection force of 33.55 kN, which was greater than the target value of 16 kN. The high strength joining between ring convex welding nut and thick plate is realized, proving that the capacitor energy storage welding machine has the advantages of energy saving, high efficiency and stable welding quality, which is suitable for the welding between large nut sizing over M10 and thick plate.

In view of the situation that existing CAPP system for engine valve is difficult to directly group and establish a database problem for the valve parts made by the enterprise, a valve part grouping program was developed based on grouping technology. For the problem that CAPP system characteristic cannot indicate clearly after matching the positions needing modification for the existing process files, the relationship between valve part characteristic and machining was simulated based on numerical control technology, and a new matching program of valve parts characteristic was developed.

Due to the effect of internal stress, cold stamped fender has springback deformation, resulting in dimensional deviation. In order to optimize the size of finished parts, CAE simulation tool is used to compensate the springback of parts in the early stamping process design. Taking the steel fender as an example, this paper elaborates a springback compensation method based on the analysis results of CAE simulation, which corrects the position that the size does not meet the standards on the basis of perfecting the simulation file, setting the scale, optimizing the process method, and positioning the parts of the fender. This method is verified by actual production inspection that the dimensional accuracy of the parts is effectively improved.

Macro and micro fracture analysis shows that the ignition coil fixing bolt is mainly fractured by torsional load, and the micro fracture is a clockwise shear dimple. Through comparative analysis of simulated assembly test, the fracture surface of the failed part is consistent with the fracture surface of the bolt under pure torsional load, so the fracture mode of the bolt is torsional fracture failure (shear stress). The cause of torsional fracture may be that when the spark plug is replaced for the second time, the bolt is not screwed in normally (the internal thread is damaged or the bolt is screwed in obliquely), and the tightening torque is higher than the torsional fracture torque (14 N·m) of the bolt, which finally leads to the torsional fracture of the bolt.

The data of wireless Andon system in the prototyping workshop can indirectly reflect the actual running state of the workshop. In this paper, Qlik Sense was used to establish the analysis model for the data of the current and historical operation states of the Andon system. The current operation state analysis mainly facilitates users to quickly obtain the operation state of the project according to the dimensions of floor/project/workshop; the analysis of historical operation status focuses on the analysis of such dimensions as bottleneck station, single vehicle manufacturing cycle and vehicle delivery in the workshop. Finally, it realized the analysis of data standardization and visualization, helped engineers and managers quickly master workshop operation information, and became an effective tool to assist business improvement.

Considering the uneven distribution of Body in White(BIW) feature points, combined with the non-spatial attributes of feature points and based on the undigraph with weight, this paper proposed a parameter adaptive DBSCAN algorithm to improve the assembly quality of BIW which can identify the regional assembly deviation of continuous off-line BIW and realize the deviation area diagnosis and automatic alarm. Experiments show that this method can effectively monitor the error source, solve various faults in time and improve the quality of vehicle manufacturing.

For the problems of long data preparation time of project engineers in the wireless torque system, this paper first disassembles the data preparation work and clarifies that the issues to be solved are 3 points with long man-hour investment from the “project standards bill of materials” to “tool correctly invoke the tightening program” and standardize the data, and at the same time combine Python, VBA and other programming tools and methods to automate this part of the work. After the actual operation of several projects, the results show that the efficiency of data preprocessing has been improved by 76%, and the use of digital methods has promoted the trial production tightening system to play a further role in promoting intelligence.

This paper studied Radio Frequency Identification (RFID) technology, briefly summarized the basic definition, components and basic working principle of this technology, and elaborated in detail the application of SICK brand RFID in automatic welding production line, parameter setting method, hardware network composition principle, software control method and information analytic mode. The vehicle model information engraved in the tag is used to realize automatic identification and mixed flow production of high and low end models on the same production line, which has advantages of simple mounting type, fast identification, accurate information. The model production assignment is passed on from the principal computer to the line, which can remotely control model ratio, has high digitization production capability, and greatly improves production efficiency and automation level.